Immunopotentiative composition

The present invention comprises compositions for immunostimulation, treatment of cancer or treatment of infectious diseases, which are characterized by inhibiting immunosuppressive signals induced by PD-1, PD-L1, or PD-L2, and the like. Regarding the treatment method using. More specifically, compositions for the treatment of cancer or infectious diseases through immunostimulation evoked as a result of inhibiting the immunosuppressive signal induced by PD-1, PD-L1, or PD-L2, and the like. Therapeutic methods using the above, immunostimulatory substances contained as active ingredients in the composition, screening methods for cancer therapeutic substances or infectious disease therapeutic substances, cell lines used in these screening methods, evaluation methods for selecting cancer therapeutic substances, and evaluation methods. It relates to a cancer cell transplanted mammal used for the evaluation.

Immunotherapy is expected to be an extremely specific treatment method because it reduces the side effects that are unavoidable in most drug therapies. In particular, since drug therapy in cancer treatment and infectious disease treatment is a treatment method that imposes a heavy burden on patients, recovery of the patient's QOL (quality of life) is emphasized, but immunotherapy Can be performed with the purpose of recovering the patient's quality of life by activating the immune response inherent in humans by an extrinsic method and taking over part of the burden of drug administration. Immunity activation can be performed by a method of activating the immune response of T lymphocytes. It is said that activation of T cells requires not only stimulation via an antigen receptor (TCR) but also additional stimulation induction via a conjugated stimulating molecule group (for example, CD28). On the other hand, recently, CTLA-4 and PD-1, which have a structure homologous to the conjugated stimulating molecule group, have been discovered, and it has been reported that they emit a signal that suppresses an antigen receptor (TCR) signal. As a method of activating T cells, it is considered that suppressing the function of this conjugation-suppressing molecule is also an effective means. PD-1 was cloned as a 55 kD type I membrane protein belonging to the immunoglobulin family (The EMBO Journal, 1992, Vol. 11, No. 11, p.3887-3895, JP-A-5-336973, Japanese Patent Application Laid-Open No. 5-336973, Kaihei 7-29 1996 issue). Human PD-1 cDNA is composed of the nucleotide sequence shown in EMBL / GenBank Acc.No.NM_005018, mouse PD-1 cDNA is composed of the nucleotide sequence shown in Acc.No.X67914, and their expression is in thymocytes. Is found in the differentiation of CD4-CD8- into CD4 + CD8 + cells (International Immunology, 1996, Vol. 18, No. 5, p.773-780, Journal of Experimental Medicine, 2000, Vol. 191), No. 5, p.891-898). In addition, the expression of PD-1 in the periphery is T cells and B cells (International) activated by stimulation from antigen receptors. Immunology, 1996, Vol. 18, No. 5, p.765-772) or it has been reported to be found in bone marrow cells containing activated macrophages. The intracellular region of PD-1 has an ITIM motif (Immunoreceptor Tyrosine-based Inhibitory Motif), which is considered to be a suppressive domain for immune response. In addition, PD-1-deficient mice have lupus-like autoimmune diseases such as glomerulonephritis and arthritis (in the case of C57BL / 6 gene background) (International Immunology, 1998, Vol. 10, No. 10, p.1563-1572, Immunity, 1999, Vol. 11, No. 2, p. 141-151) and dilated cardiomyopathy-like diseases (in the case of BALB / c gene background) (Science, 2001, Vol. 291, No. 5502, p. Since it develops .319 to 332), it is also suggested that PD-1 is a regulator of the onset of autoimmune diseases, especially peripheral autoimmune tolerance. PD-L1 which is a ligand of PD-1 (human PD-L1 cDNA is EMBL / GenBank Acc.No.AF233516, mouse PD-L1 cDNA is composed of the nucleotide sequence shown by NM_021893. ) Is expressed in so-called antigen-presenting cells such as activated monocytes and dendritic cells (Journal of Experimental Medicine, 2000, Vol. 19, No. 7, p. 1027-1034). These cells present interacting molecules that induce various immune-inducing signals to T lymphocytes, and PD-L1 is one of the molecules that induces suppression signals by PD-1. PD-L1 ligand stimulation has been shown to suppress activation of PD-1 expressing T lymphocytes (cell proliferation, induction of various cytokine production). Furthermore, PD-L1 expression is expressed not only in immunocompetent cells, but also in certain tumor cell lines (monocytic leukemia-derived cell line, mast cell line-derived cell line, liver cancer-derived cell line, neuroblast type cell line). , Various cell lines derived from breast cell lines) (see Nature Immunology, 2001, Vol. 2, No. 3, p.261-267). PD-L2 (Human PD-L2 cDNA is EMBL / GenBank Acc.No.NM_025239, mouse PD-L2cDNA is composed of the nucleotide sequence shown by NM_021896 (Nature Immunology, 2001, Vol. 2, No. 3, p.261-267). ) Was identified as the second ligand for PD-1, but its expression and function have been reported to be similar to PD-L1. Inhibitory signals from conjugated inhibitory molecules represented by PD-1 are immune tolerance and self-antigens during lymphocyte development or maturation by a mechanism that appropriately regulates positive signals by antigen receptors (TCRs) and conjugated stimulator molecules. It is believed to control the abnormal immune response to. Also, certain tumors and viruses use direct or indirect mechanisms to block T cell activation and proliferation and use these conjugation-suppressing molecules to weaken the host immune response to themselves. It is considered (see Cell, 1992, Vol. 71, No. 7, p.1093 ~ 1102, Science, 1993, Vol. 259, No. 5093, p.368 ~ 370). Furthermore, in some diseases that are thought to be caused by T cell dysfunction, abnormalities in these conjugation-suppressing molecules are thought to cause T cell dysfunction.

An object of the present invention is to provide a composition that inhibits an inhibitory signal by PD-1, PD-L1 or PD-L2 to activate immunostimulation, and a composition for treating cancer or infectious disease through this mechanism. It is in. The present inventors focused on PD-1, PD-L1 or PD-L2 as a new target in the treatment of cancer or infectious diseases, and produced an inhibitory signal by PD-1, PD-L1 or PD-L2. It has been found that the inhibitory substance inhibits the growth of cancer through the recovery of immune function and the activation mechanism. Furthermore, they found that PD-1 signals, specifically the interaction between PD-1 and PD-L1 or PD-1 and PD-L2, are involved in the elimination of infected viruses. Based on these facts, we have found that a substance that inhibits the inhibitory signal by PD-1, PD-L1 or PD-L2 has a therapeutic effect on cancer or infectious diseases, and completed the present invention. That is, the present invention 1. An immunostimulatory composition comprising an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2. 2. A cancer therapeutic composition comprising an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2. 3. The cancer treatment composition according to item 2 above, which is a composition that suppresses cancer metastasis. 4. Infectious disease therapeutic composition, which comprises an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2. 5. The cancer therapeutic composition according to the above item 2 or 3, which is characterized by acting through immunostimulation. 6. The infectious disease treatment composition according to item 4 above, which is characterized by acting through immunostimulation. 7. From PD-1 and PD-L1 or PD-1 and PD-L2 interaction inhibitors, PD-1 intracellular signal inhibitors, and PD-1, PD-L1 or PD-L2 production inhibitors The composition according to any one of the above items 1 to 6, which is one or more immunosuppressive signal inhibitors selected. 8. Composition according to item 7 above, which is an interaction inhibitor of one or more PD-1 and PD-L1 selected from PD-1 antibody, PD-L1 antibody, solubilized PD-1, and solubilized PD-L1. Stuff, 9. Select from anti-human PD-1 antibody produced by hybridoma identified by international accession number FERM BP-8392, anti-PD-1 antibody obtained by humanizing non-human antibody, and fully human anti-human PD-1 antibody. The composition according to item 8 above, which is a PD-1 antibody to be produced. 10. The composition according to any one of the above items 1 to 6, wherein the lymphocyte cell whose PD-1 expression is inhibited by gene modification is an immunosuppressive signal inhibitor. 11. PD-1 and PD-L1 or PD-1 and PD-L2 interaction inhibitor, PD-1 intracellular signal inhibitor, or PD-1, PD-L1 or PD-L2 production inhibitor The composition according to item 7 above, which is one or more substances selected from proteins, polypeptides or peptides, polynucleotides or polynucleosides, antibodies or derivatives thereof, organic synthetic compounds, inorganic compounds, and natural products. 12. An immunostimulatory method consisting of administration of an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2, 13. A cancer treatment method consisting of administration of an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2, 14. Suppressing cancer metastasis The cancer treatment method described in Section 13 above, 15. Infectious disease treatment methods consisting of administration of PD-1, PD-L1 or PD-L2 immunosuppressive signal inhibitors, 16. The cancer treatment method according to the preceding paragraph 13 or 14, which is characterized by acting through immunostimulation. 17. The method for treating infectious diseases according to the above item 15, which is characterized by acting through immunostimulation. 18. From PD-1 and PD-L1 or PD-1 and PD-L2 interaction inhibitors, PD-1 intracellular signal inhibitors, and PD-1, PD-L1 or PD-L2 production inhibitors The method according to any one of the preceding paragraphs 12 to 17, which is one or more immunosuppressive signal inhibitors selected. 19. The method according to item 18 above, which is an interaction inhibitor of one or more PD-1 and PD-L1 selected from PD-1 antibody, PD-L1 antibody, solubilized PD-1, and solubilized PD-L1. , 20. Selected from anti-human PD-1 antibody produced by hybridoma identified by international accession number FERM BP-8392, PD-1 antibody obtained by humanizing non-human antibody, and fully human anti-human PD-1 antibody. PD-1 antibody according to the method described in the preceding paragraph 19. 21. The method according to any one of items 12 to 17 above, wherein the lymphocyte cells whose PD-1 expression is inhibited by gene modification are immunosuppressive signal inhibitors. 22. PD-1 and PD-L1 or PD-1 and PD-L2 interaction inhibitors, PD-1 intracellular signal inhibitors, or PD-1, PD-L1 or PD-L2 production inhibitors The method according to item 18 above, which is one or more substances selected from proteins, polypeptides or peptides, polynucleotides or polynucleosides, antibodies or derivatives thereof, organic synthetic compounds, inorganic compounds, and natural products. 23. Use of PD-1, PD-L1, or PD-L2 immunosuppressive signal inhibitors to produce immunostimulatory compositions, 24. Use of PD-1, PD-L1, or PD-L2 immunosuppressive signal inhibitors to produce cancer therapeutic compositions, 25. Use of the substance according to the above item 24, wherein the cancer treatment composition is a cancer metastasis suppressing composition. 26. Use of PD-1, PD-L1, or PD-L2 immunosuppressive signal inhibitors to produce infectious disease therapeutic compositions, 27. Screening cancer cell lines transformed to express PD-L1 or PD-L2, 28. An immunostimulatory substance, which comprises contacting the cells, lymphocyte cells and test substance described in the preceding item 27 to evaluate the enhancing effect of the test substance on the immune response of the lymphocyte cells to the cells described in the preceding item 27. Screening method, 29. By contacting the cells, lymphocyte cells and test substance described in the preceding paragraph 27, which are cancer cells, the effect of enhancing the test substance on the immune response of the lymphocyte cells to the cancer cells or the effect of inhibiting the growth of the tumor cells. A method for screening cancer therapeutic substances, which is characterized by evaluation. 30. The test substance against the immune response of the lymphocyte cells to the infected cells by contacting the cells according to the previous item 27 or the cells expressing PD-L1 or PD-L2, the lymphocyte cells and the test substance infected with the pathogen. A method for screening an infectious disease therapeutic substance, which comprises evaluating an enhancing effect or an inhibitory effect on pathogen growth. 31. Mammals produced by transplanting the cancer cell lines described in 27 above. 32. The present invention relates to a method for selecting a cancer therapeutic substance, which comprises administering a test substance to the mammal described in the preceding paragraph 31 and evaluating the suppression rate of the test substance on the growth of transplanted cancer cells or the survival rate of the transplanted mammal. .. PD-1, PD-L1 or PD-L2 in the present invention include those derived from primate mammals including mice, rats, hamsters, guinea pigs, dogs, pigs, monkeys or humans, respectively. Preferably, it is human PD-1, human PD-L1 and human PD-L2. The immunosuppressive signal by PD-1, PD-L1 or PD-L2 in the present invention is at least the interaction between PD-1 and PD-L1 or PD-1 and PD-L2, and the intracellular signal of PD-1. Consists of. In addition, this includes the production of PD-1, PD-L1 or PD-L2 molecules themselves. The immunosuppressive signal by PD-1, PD-L1 or PD-L2 in the present invention is the interaction between PD-1 and PD-L1 or PD-1 and PD-L2 or the intracellular signal of PD-1. It is inhibited by direct or indirect inhibition. Examples of the substance having these inhibitory activities include substances that selectively bind to PD-1, PD-L1, or PD-L2, respectively. Preferred include, for example, proteins, polypeptides or peptides, polynucleotides or polynucleosides, antibodies or derivatives thereof, synthetic organic compounds, inorganic compounds, or natural products. In particular, a substance having excellent specificity includes an antibody against PD-1, PD-L1 or PD-L2. The immunosuppressive signal is also inhibited by inhibition of the production of the PD-1, PD-L1 or PD-L2 molecule itself. Antibodies to PD-1, PD-L1 or PD-L2 are human-derived antibodies, mouse-derived antibodies, or rat-derived antibodies as long as they inhibit the immunosuppressive signal by PD-1, PD-L1 or PD-L2. Antibodies, rabbit-derived antibodies or goat-derived antibodies may be used, and their polyclonal or monoclonal antibodies, complete or shortened (eg, F (ab')).₂, Fab', Fab or Fv fragment) antibody, chimeric antibody, humanized antibody or fully human antibody. Such an antibody can be produced according to a known antibody or antiserum production method using a partial protein in the extracellular region of PD-1, PD-L1 or PD-L2 as an antigen. Partial proteins in the extracellular region can be prepared by known protein expression and purification methods. The polyclonal antibody can be produced by a known method. For example, it can be produced by immunizing an appropriate animal with an antigen protein or a mixture thereof and a carrier protein, collecting an antibody-containing substance against the antigen protein from the immunized animal, and separating and purifying the antibody. Animals used generally include mice, rats, sheep, goats, rabbits and guinea pigs. A complete Freund's adjuvant or an incomplete Freund's adjuvant can be administered together with the antigen protein in order to enhance the antibody-producing ability. The administration is usually performed once every two weeks, for a total of about 3 to 10 times. The polyclonal antibody can be collected from the blood, ascites, etc. of an animal immunized by the above method. Measurement of polyclonal antibody titer in antiserum can be measured by ELISA method. Separation and purification of polyclonal antibodies are, for example, purification methods using an antigen-binding solid phase or an active adsorbent such as protein A or protein G, salting out method, alcohol precipitation method, isoelectric point precipitation method, electrophoresis method, ion exchange. It can be carried out according to a method for separating and purifying immunoglobulin such as a body adsorption / desorption method, an ultracentrifugation method, and a gel filtration method. As the antibody preparation, a monoclonal antibody or a modified product thereof is more preferable. To prepare monoclonal antibody-producing cells, select individuals with antibody titers from animals immunized with the antigen, collect spleen or lymph nodes 2 to 5 days after final immunization, and select the antibody-producing cells contained therein. This can be done by producing a monoclonal antibody-producing hybridoma that can be subcultured by fusing with myeloma cells of the same or heterologous animal. The antigen protein is administered to a site where antibody production is possible by itself, a carrier, or a diluent. For administration, a complete Freund's adjuvant or an incomplete Freund's adjuvant is generally administered in order to enhance the antibody-producing ability. Animals can also be immunized by a method called "DNA immunization". In this method, the tibialis anterior muscle of an immune animal is treated with Cardiotoxin, and a vector expressing an antigen protein is introduced. Then, the vector is incorporated into muscle cells in the process of tissue repair, and the protein is incorporated into the muscle cells. (Nature Immunology, 2001, Vol. 2, No. 3, p.261-267). The immunized animal can be a mouse, rat, sheep, goat, rabbit or guinea pig, but a mouse or rat is preferably used. The fusion operation can be carried out by the method of Kohler and Milstein (Nature, 1975, Vol. 256, No. 5517, p.495-497), and polyethylene is used as a fusion accelerator. Glycol (PEG), Sendai virus, etc. are used. Examples of myeloma cells include myeloma cells such as P3U1, NS1, SP2 / 0, and AP1, but P3U1 is usually commonly used. The selection of monoclonal antibody-producing cells can be carried out, for example, by detection by an ELISA method by adding a hybridoma culture supernatant to a solid phase in which an antigen protein is directly adsorbed or adsorbed together with a carrier. Furthermore, the antibody titer of the hybridoma culture supernatant can be measured by the ELISA method. The separation and purification of the monoclonal antibody can be carried out according to the same immunoglobulin separation and purification method as that of the polyclonal antibody above. Specifically, it is an anti-human PD-1 antibody produced by a hybridoma identified by international accession number FERM BP-8392 or an anti-mouse PD-L1 antibody produced by a hybridoma identified by international accession number FERM BP-8396. .. The hybrid doma identified by the international accession number FERM BP-8392 was dated December 19, 2002, 1-1-1, Higashi, Tsukuba-shi, Ibaraki, Japan, Chuo No. 6 (postal code 305-8566), Incorporated Administrative Agency Industrial Technology Research. It was deposited at the Patent Organism Depositary Center under the accession number FERM P-19162 and transferred to the International Deposit on June 5, 2003. The hybridoma identified by the international deposit number FERM BP-8396 was deposited with the center on June 25, 2002 under the accession number FERM P-18908, and was transferred to the international deposit on June 11, 2003. .. An antibody fragment is F (ab')₂, Fab', Fab or scFv antibody fragment, which can be obtained by treatment with a protease enzyme and optionally reduction. F (ab')₂The antibody fragment can be purified by completely digesting the purified monoclonal antibody with pepsin and purifying it by any method of ion exchange chromatography, gel filtration, affinity chromatography such as protein A or protein G column. The digestion time of pepsin depends on the Ig subtype and should be prepared appropriately. Fab'antibody fragment prepared F (ab')₂Can be prepared by partial reduction with 2-mercaptoethylamine. In addition, the Fab antibody fragment can be prepared by directly digesting with the digestive enzyme papain in the presence of cysteine and purifying it. In addition, a monoclonal antibody can be modified by gene recombination technology to produce a modified antibody or a hybrid antibody by determining the amino acid sequence of the antibody or using a DNA sequence encoding an antibody that can be isolated from a hybridoma. Is. For example, it can be prepared as a single chain antibody instead of the usual complete antibody. The scFv antibody (Single Chain Fv) can be produced by the method of Jost et al. (Journal of Biological Chemistry, 1994, Vol. 269, No. 42, p.26267-26273). Originally, by linking DNA fragments encoding the variable regions of heavy and light chains with spacers encoding neutral amino acids (glycine or serine) and expressing an expression vector containing this fusion DNA in an appropriate host cell. It is possible to prepare a single-chain antibody that retains the characteristics and affinity of the antibody of. When using a non-human antibody for the treatment of humans, it is essential to reduce the antigenicity of the antibody. The immune response of a patient to an antibody often shortens the effective treatment period and requires steps to humanize or fully humanize the antibody and reduce the antigenicity of the antibody. A humanized antibody that has been modified to allow administration to humans is modified to reduce antigenicity or improve blood kinetics to the extent that the antibody is pharmacologically acceptable when administered to humans. It is an antibody that has been produced. The human PD-1 antibody or human PD-L1 antibody in the specification of the present invention also includes an antibody obtained by humanizing or fully humanizing the antibody. A humanized antibody can be produced by substituting a part of a non-human antibody produced by immunizing a non-human mammal with a part of a human antibody. Specifically, it is known that it can be produced by constructing a chimera with a gene encoding a constant region of a human antibody (Proc. Natl. Acad. Sci. (USA), 1987, Vol. 84, p. .3439 ~ 3443, Journal of Immunology, 1987, Vol. 139, No. 1, p.3521). Human constant region DNA sequences are described in the literature, and the constant region genes are readily available from known clones. Subsequently, the DNA sequence encoding the variable region of the antibody is fused to the sequence of the human constant region. Human constant region isotypes can be selected by desired effector function or activity in antibody-dependent cytotoxicity. Preferred isotypes are IgG1, IgG3 and IgG4. In addition, any of the human light chain constant region, the κ chain or the λ chain can be used. This humanized chimeric antibody can be expressed by conventional methods. Completely human antibodies are mice into which the constant region gene of human immunoglobulin has been introduced (Xenomouse (Chemical Biology, 2000, Vol. 7, No. 8, p.R185-6), human immunoglobulin (infection and immunity,). 2002, Vol. 70, No. 2, p.612-9), TC Mouse (Biotechnology and Genetics Enginnering) It can be produced using Revew, 2002, Vol. 19, p.73-82), KM mouse (Cloning Stem Cells, 2002, Vol. 4, No. 1, p.91-102)). Furthermore, antibody-producing lymphocytes isolated from these mice can be used as hybridomas to mass-produce the desired antibody. It can also be prepared by the phage display method (FEBS Letter, 1998, Vol. 441, p.20-24). In this method, a human antibody can be expressed on the surface of a phage in a form fused with an outer shell protein constituting the phage by utilizing a phage in which a human antibody gene is incorporated into a circular single-stranded DNA. A polypeptide or derivative thereof that binds to PD-1, PD-L1, or PD-L2 is a partial protein of PD-1, PD-L1, or PD-L2 that does not induce an immunosuppressive signal. Can be mentioned. The presence of PD-1 in the vicinity of antigen receptors is essential for the induction of PD-1 immunosuppressive signals, for which PD-L1 or PD-L2 is present in antigen-presenting cells, tumors or cancer cells. Constrained by interaction with. Thus, solubilized PD-L1 or solubilized PD-L2, which has only the extracellular domain and a portion that interacts with PD-1, can inhibit the immunosuppressive signal of PD-1. Conversely, solubilized PD-1, which has a similar structure and is capable of binding PD-L1 or PD-L2, can also inhibit immunosuppressive signals. These solubilized proteins may be prepared by known protein expression methods and purification methods as long as they contain sufficient extracellular space necessary for binding to PD-1, PD-L1 or PD-L2. it can. When PD-1 and PD-L1 or PD-1 and PD-L2 interaction inhibitors are proteins or polypeptides, and the regions essential for their interaction consist only of contiguous polypeptides. Such polypeptide fragments can be antagonistic to each other. Furthermore, it becomes possible to identify an antagonist having stronger activity from a group of molecules in which this polypeptide fragment is chemically modified or designed by a computer based on the three-dimensional structure of the polypeptide fragment. It is also possible to more efficiently select the optimum antagonist molecule from the group of molecules designed by a computer based on the protein three-dimensional structure analysis data of the interaction region. In addition, substances that inhibit the interaction between PD-1 and PD-L1 or PD-1 and PD-L2 can be directly screened. Such substances can be proteins, polypeptides or peptides, polynucleotides or polynucleosides, non-peptide compounds, synthetic organic compounds, or natural products (eg, fermented products, cell extracts, plant extracts, animal tissue extracts). ) Can be identified from the library. The inhibitory signal of the PD-1 intracellular domain is a dephosphorylating enzyme bound to the PD-1 intracellular domain ITIM (eg, SHP-1, 2 (Sathish JG, Journal of Immunology), 2001, Vol. 166). , No. 3, p.1763-70) is caused by contact with the intracellular complex of the antigen receptor complex, and is therefore generally inhibited by inhibition of contact between the antigen receptor complex and PD-1. .. Substances that inhibit the inhibitory signal include substances that inhibit the phosphorylation of tyrosine residues of ITIM, substances that inhibit the binding of dephosphorylating enzyme to ITIM, and substances that directly inhibit the activity of the dephosphorylating enzyme. Be done. Examples of the antigen receptor complex include a T cell receptor complex and a B cell receptor complex. The production of PD-1, PD-L1, or PD-L2 can be inhibited by certain polynucleotides or polynucleosides, synthetic organic compounds, inorganic compounds, natural products, and the like. In particular, suitable polynucleotides or polynucleosides include antisense nucleotide derivatives called ribozymes. This utilizes the mechanism by which the expressed mRNA is disrupted by introducing a polynucleotide derivative complementary to the mRNA of PD-1, PD-L1 or PD-L2 into the target expressing cell. .. In addition, the vector can be used for genetic manipulations such as inhibiting PD-1 expression on lymphocyte progenitor cells taken from a patient, and the manipulated cells are proliferated, differentiated, and activated. , Can be used for cell medicine to be administered to patients again. In particular, in immunotherapy for cancer, a more clonal lymphocyte cell specific to the target cell is prepared by adding a specific antigen of the target cell during maturation and activation of the lymphocyte progenitor cell. be able to. The screening method of the present invention can be carried out by a method of measuring cell function. The screening cancer cell line transformed to express PD-L1 or PD-L2 used in the same method is a known method of an expression vector constructed to express PD-L1 or PD-L2. Includes transiently or stably transformed cancer cell lines introduced into cells by. The cancer cell lines used include monkey COS-1 cells, COS-7 cells, Vero, Chinese hamster cell CHO (hereinafter abbreviated as CHO cells), and dhfr gene-deficient Chinese hamster cell CHO (hereinafter, CHO (dhfr)). -) Abbreviated as cells.), Mouse L cells, mouse AtT-20, mouse myeloma cells, rat GH3, HEK293T cells, human FL cells, etc. are used. In particular, when transforming animal cells, for example, "Cell Engineering Separate Volume 8 New Cell Engineering Experiment Protocol" (Shujunsha, 1995, No. 263) and "Virology" (1973, Vol. 52, No. 456). It can be carried out according to the method described in (No.). In addition, cells that naturally express PD-L1 or PD-L2 can also be used. Such cells include leukocyte cells, preferably monocytes, macrophages or antigen presenting cells, epithelial cells, tumor cells, cancer cells or cell lines thereof. As cells that can be used as tumor cells or cancer cells, for example, P38D1 cells, P815 cells, NB41A3 cells, MDA-231 cells, SKBR-3 cells, MCF-7 cells, BT474 cells, J558L cells, P3U1 cells, PAI cells, X63 Cells or SP2 / 0 cells can be used. Cells that naturally express PD-L1 or PD-L2 or cells that are forcibly expressed and infected with a pathogen can also be used. The pathogens to infect include human hepatitis virus (hepatitis B, hepatitis C, hepatitis A) or hepatitis E), human retrovirus, human immunodeficiency virus (HIV1, HIV2), human T-cell leukemia virus, human T. Lymphotropic viruses (HTLV1, HTLV2), simple herpesvirus type 1 or 2, Epstein bar virus, cytomegalovirus, varicella-herpes zoster virus, human herpesvirus including human herpesvirus 6, poliovirus, measles virus, Eczema virus, Japanese encephalitis virus, mumps virus, influenza virus, adenovirus, enterovirus, rhinovirus, virus that causes severe acute respiratory syndrome (SARS), Ebola virus, West Nile virus, or artificially modified Virus is mentioned. Other pathogens include, for example, pathogenic protozoa (eg, tripanosoma, malaria and toxoplasma), bacteria (eg, mycobacterium, salmonella and listeria), or fungi (eg, candida). The lymphocyte cells used in the screening method of the present invention are T cells or B cells, preferably cytotoxic T lymphocytes (CTL). In addition, the immune reaction of lymphocytes in the screening method of the present invention includes cytotoxic reaction (for example, tumor immune reaction), mixed lymphocyte reaction, production of cytokines, antibodies, complement or other cell surface antigens, or cell proliferation. Can be mentioned. The method for screening the active ingredient of the immunostimulatory or cancer therapeutic composition of the present invention specifically measures the cytotoxic activity of cytotoxic T lymphocytes on target cells and quantifies the effect of the test substance on the activity. It can be done by. This method is derived from cytotoxic T lymphocytes (CTL) or cell lines (eg, 2C cells) that spontaneously express PD-1 and syngeneic mice and spontaneously express PD-L1 or PD-L2. Alternatively, the recovery or enhancement of cytotoxic activity by adding a test substance to a mixed culture of forcibly expressed cells is quantified. The feature of this method is that the cytotoxic activity against cells expressing PD-L1 or PD-L2 is lower than the cytotoxic activity against cells expressing PD-L1 or PD-L2, and the cells caused by the test substance. The recovery (increased range) of the injury activity can be measured more clearly. The recovery of cytotoxicity by the test substance can be evaluated as corresponding to the inhibition of cytotoxicity suppression by PD-L1 or PD-L2, which is a feature of the present invention. Furthermore, it is more desirable to arbitrarily measure the cytotoxicity of the test substance. The cells used for this include tumor cell lines or cancer cell lines that naturally express PD-L1 or PD-L2 (Nature Immunology, 2001, Vol. 2, No. 3, p.261-267). For example, P38D1 cells, P815 cells, NB41A3 cells, MDA-231 cells, SKBR-3 cells, MCF-7 cells, BT474 cells, J558L cells, P3U1 cells, PAI cells, X63 cells, or SP2 / 0 cells can be used. However, tumor cell lines or cancer cell lines transformed to stably or transiently express PD-L1 or PD-L2 can also be used. On the other hand, the cytotoxic lymphocytes that can be used are those expressing PD-1, and are preferably cells derived from animals of the same lineage as the target cells. Screening of the active ingredient of the infectious disease treatment composition of the present invention infected a cytotoxic T lymphocyte (CTL) or cell line (eg, 2C cell), pathogen or virus that naturally expresses PD-1. Enhancement of the immune response of lymphocyte cells to infected cells by adding a test substance to a mixed culture of cells in which PD-L1 or PD-L2 derived from the same strain is naturally expressed or forcibly expressed. It quantifies the action or the inhibitory action on the growth activity of pathogenic bacteria or viruses. Furthermore, in an evaluation method using the same principle, a screening cancer cell line transformed to express PD-L1 or PD-L2 described above or a cell that naturally expresses PD-L1 or PD-L2 is selected. , Mammals produced by transplantation into syngeneic mammals can be used. As a step of producing, a step of transplanting cells and a step of breeding the mammal until the evaluation target becomes appropriate are indispensable. This evaluation method is based on the proliferation of transplanted cells, the amount of various cytokines or cell surface antigens produced, especially when the cells are cancer cells, histological analysis of the proliferation, infiltration or metastasis of the cells, or the survival of the transplanted mammal. It is characterized by evaluating the rate. Cell proliferation can be evaluated by the number of cancer cells per unit volume in the case of ascites cancer or hematological cancer, and by the size or weight after excision in the case of solid cancer. The cancer therapeutic effect of the test substance in this method can be evaluated as corresponding to the effect derived from the inhibition of cytotoxicity suppression by PD-L1 or PD-L2. As the cancer cell line to be transplanted, any cancer cell that can be used in the in vitro screening method can be used, but those derived from the same lineage as the transplanted mammal and having good proliferation are more preferable. Mammals include non-human primates, mice, rats, hamsters, guinea pigs, dogs, pigs and monkeys.

The present inventors remarkably suppress the growth of cancer and exert an effect of prolonging the life of an individual by administration to a cancer cell transplanted animal model, and each of them specifically inhibits the functions of PD-1 and PD-L1. He invented antibodies (anti-PD-1 antibody, anti-PD-L1 antibody). These antibodies showed the effect of recovering or enhancing the cytotoxic activity, which is relatively decreased by the presentation of PD-L1 ligand to CTLs (cytotoxic T lymphocytes) expressing PD-1 (implemented). Example 1, see Figure 1). This suggests that the cytotoxic activity of CTL on cancer cells can be enhanced by administration of these antibodies. Furthermore, administration of anti-PD-L1 antibody was performed in a cancer cell transplant animal model (protein / nucleic acid / enzyme, 1981,) using syngeneic mice into which a mastocytoma-derived cell line artificially expressed PD-L1 was transferred. In Volume 26, No. 3, p.208-224), the growth, invasion and metastasis of cancer cells were suppressed, and the life-prolonging effect of the individual was shown (see Fig. 2 and Fig. 3). Furthermore, it was suggested that an effect similar to the effect of inhibiting PD-L1 function by this antibody can be obtained by inhibiting PD-1 function or production. This is because no proliferation of transferred cancer cells was observed in the cancer transfer model using PD-1-deficient mice, indicating that inhibition of PD-1 function or production is also an effective cancer treatment method. (See Examples 5 and 5). In fact, in a cancer cell transplant animal model, administration of anti-PD-1 antibody was demonstrated to significantly suppress the metastasis of transferred cancer cells to the liver (see Example 13). Furthermore, the inventors have shown that substances that inhibit the immunosuppressive signal induced by PD-1, PD-L1, or PD-L2 are useful in the treatment of infectious diseases (Examples 11, 15). Figure, see Figure 16). These results experimentally shown by the present inventors do not indicate that only PD-1 antibody or PD-L1 antibody exhibits the above-mentioned effects, but PD-1, PD-L1 or PD-L2. It proves that any substance that can inhibit the immunosuppressive signal from the above exerts almost the same effect. Examples of substances having such an effect include anti-PD-L2 antibody, solubilized PD-1, solubilized PD-L1, solubilized PD-L2, PD-1 antagonist, PD-L1 antagonist, PD-L2. Antagonists, substances that inhibit the interaction between PD-1 and PD-L1 or PD-1 and PD-L2, PD-1 production inhibitors, PD-L1 production inhibitors, PD-L2 production inhibitors, or PD- Examples include intracellular inhibitory signal inhibitors according to 1. Cancers or tumors that are expected to be effective by administration of the cancer therapeutic composition of the present invention include, for example, carcinoma, squamous adenocarcinoma (eg, cervical canal, eyelid, conjunctival, vaginal lung, oral cavity, skin, bladder, Tongue, throat, esophagus), adenocarcinoma (eg, prostate, small intestine, endometrium, cervical canal, large intestine, lung, pancreas, esophagus, rectum, uterus, stomach, breast, ovary). In addition, sarcomas (eg, myogenic sarcomas), leukemias, neuromas, melanomas, lymphomas are also included. Among these cancers or tumors, the effect is particularly remarkable for those that significantly express PD-L1 or PD-L2. The expression of PD-L1 or PD-L2 can be identified by a test using a surgically resected cancer or tumor mass or a lesion collected outside the body as a sample, and administration of the composition of the present invention is PD-L1 or PD. -It is an efficient and effective method for post-surgical treatment of patients with tumors or cancers that are prominently expressing L2. Identification of PD-L1 or PD-L2 expression can be examined, for example, by immunochemical methods using PD-L1 or PD-L2 antibodies, RT-PCR or DNA array methods. Chemotherapy and radiation therapy for cancer inevitably have the side effect of drastically reducing the proliferation of lymphocytes. Administration of the composition of the present invention has the effect of stimulating and proliferating reduced lymphocyte cells, and can minimize the severe side effects associated with conventional chemotherapy. The same applies to radiation therapy. In addition, when used in combination with the composition of the present invention, the dose or irradiation radiation dose of the chemotherapeutic agent can be significantly reduced from the commonly used dose or irradiation dose. The cancer therapeutic composition of the present invention can be used in combination with or combined with an existing chemotherapeutic agent. Such chemotherapeutic agents include, for example, alkylating agents, nitrosourea agents, antimetabolites, anticancer antibiotics, plant-derived alkaloids, topoisomerase inhibitors, hormone therapies, hormone antagonists, aromatase inhibitors, P sugars. Examples include protein inhibitors, platinum complex derivatives, other immunotherapeutic agents or other anti-cancer agents. Furthermore, it can be used in combination with or combined with a leukocyte (neutropenia) hypotensive agent, a thrombocytopenic therapeutic agent, an antiemetic agent, and a cancer pain therapeutic agent, which are cancer therapeutic aids for recovering the QOL of patients. The cancer therapeutic composition of the present invention can be used in combination with or combined with other immunostimulatory substances. Examples of such immunostimulatory substances include various cytokines and tumor antigens. Examples of cytokines that stimulate the immune response include GM-CSF, M-CSF, G-CSF, interferon-α, β, γ, IL-1, IL-2, IL-3, IL-12, and the like. .. In addition, B7 ligand derivatives, anti-CD3 antibody and anti-CD28 antibody, and anti-CTLA-4 antibody can also enhance the immune response. Administration of a cancer antigen can also enhance the specific immune response of T lymphocytes to cancer cells, and can provide additional or synergistic enhancement in combination with the cancer therapeutic composition of the present invention. The cancer antigen can be prepared as a purified protein if the gene is clear, or as a lysate of the cancer cell itself if the gene is unknown. Examples of such cancer antigens include HLA-A1 and HLA-A2 binding peptides derived from MAGE-1 and MAGE-3 of malignant melanoma, and MART-1, gp100. In addition, HER2 / neu peptide for breast cancer and ovarian cancer, MUC-1 peptide for adenocarcinoma, and NY-ESO-1 for metastatic cancer can be mentioned. The virus is believed to utilize T lymphocyte cell conjugation suppressors as a way to escape the immune defenses of infected hosts (Journal Experimental Medicine, 2000, Vol. 191, No. 11). , p. 1987 ~ 1997). Viral infection is partly due to such a virus escaping function, and it is considered that administration of the composition of the present invention can enhance the immune response of T lymphocyte cells to the virus. Administration of the infectious disease treatment composition of the present invention includes, for example, human hepatitis virus (hepatitis B, hepatitis C, hepatitis A or hepatitis E), human retrovirus, human immunodeficiency virus (HIV1, HIV2), human. It is effective in treating infection with T-cell leukemia virus or human T-lymphotropic virus (HTLV1, HTLV2). In addition, simple herpesvirus types 1 and 2, Epstein bar virus, cytomegalovirus, varicella-herpesvirus, human herpesvirus including human herpesvirus 6, poliovirus, measles virus, ruin virus, Japanese encephalitis virus, mumps It is also considered to be effective in treating infections with viruses, influenza viruses or cold viruses such as adenovirus, enterovirus or rhinovirus, viruses that develop severe acute respiratory syndrome (SARS), Ebola virus, or Western Nile virus. Other pathogens are also effective against infection by, for example, pathogenic protozoa (eg, tripanosoma, malaria and toxoplasma), bacteria (eg, Mycobacterium, Salmonella and Listeria) or fungi (eg, Candida). Conceivable. The infectious disease therapeutic composition of the present invention can be used in combination with or combined with existing anti-HIV agents, antiviral agents, antibiotic preparations, antibacterial agents, and visceral mycosis therapeutic agents. As anti-HIV agents, for example, reverse transcriptase inhibitors (eg, AZT, ddI, 3TC, d4T), protease inhibitors (eg, saquinavir mesylate, ritonavir, nelfinavir mesylate, amprenavir, delavirdine mesylate, saquinavir, etc. Lopinavir / ritonavir), or CCR5 receptor antagonists. Examples of antiviral agents include anti-herpesviral agents, anti-influenza virus agents, interferon-α and β, and various immunoglobulins. The infectious disease therapeutic composition of the present invention can be formulated in combination with or together with a viral or pathogen vaccine. Such vaccines include, for example, polio vaccine, measles vaccine, Japanese encephalitis vaccine, BCG vaccine, triple vaccine, mumps vaccine, varicella vaccine, influenza vaccine, hepatitis A vaccine, hepatitis B vaccine, or cholera vaccine. Can be mentioned. The compositions of the present invention are usually administered systemically or topically, orally or parenterally. The dose varies depending on the drug used in the present invention, and at the same time, varies depending on age, body weight, symptoms, therapeutic effect, administration method, treatment time, etc., but in the case of oral administration, it is usually 1 μg per adult. It is administered once to several times daily in the range of 100 mg. In the case of parenteral administration, it is administered once to several times a day in the range of 0.1 ng to 10 mg per adult, and the parenteral administration form is preferably intravenous administration, 1 It is continuously administered intravenously for 1 to 24 hours a day. Of course, as described above, since the dose varies depending on various conditions, an amount smaller than the above dose may be sufficient, or administration beyond the range may be necessary. When administering a concomitant drug of the composition of the present invention and another drug, an internal solid preparation for oral administration, an internal liquid preparation, and an injection, an external preparation, a suppository, or an inhalation for parenteral administration. It is used as an agent, nasal agent, etc. Oral solid preparations for oral administration include tablets, pills, capsules, powders, granules and the like. Capsules include hard capsules and soft capsules. Further, the tablets include sublingual tablets, intraoral patches, orally rapidly disintegrating tablets and the like. In such solids for internal use, one or more active substances are left as they are, or excipients (lactoose, mannitol, glucose, microcrystalline cellulose, starch, etc.) and binders (hydroxypropyl cellulose, polyvinylpyrrolidone, etc.) It is mixed with a disintegrant (calcium fibrolic glycolate, etc.), a lubricant (magnesium stearate, etc.), a stabilizer, a solubilizing agent (glutamic acid, aspartic acid, etc.), etc. It is used as a formulation. Further, if necessary, it may be coated with a coating agent (sucrose, gelatin, hydroxypropyl cellulose, hydroxypropyl methylcellulose phthalate, etc.), or may be coated with two or more layers. Also included are capsules of absorbable substances such as gelatin. Sublingual tablets are manufactured according to known methods. For example, one or more active substances include excipients (lactose, mannitol, glucose, microcrystalline cellulose, colloidal silica, starch, etc.), binders (hydroxypropyl cellulose, polyvinylpyrrolidone, magnesium aluminometasilicate, etc.), disintegration. Agents (starch, L-hydroxypropyl cellulose, carboxymethyl cellulose, croscarmellose sodium, calcium fibrin glycolate, etc.), lubricants (magnesium stearate, etc.), swelling agents (hydroxypropyl cellulose, hydroxypropylmethyl cellulose, carbopole, etc.) Stable carboxymethyl cellulose, polyvinyl alcohol, xanthan gum, guar gum, etc.), swelling aids (glucose, fructose, mannitol, xylitol, erythritol, maltose, trehalose, phosphate, citrate, silicate, glycine, glutamate, arginine, etc.) It is mixed with an agent, a solubilizing agent (polyethylene glycol, propylene glycol, glutamate, aspartic acid, etc.), a flavoring agent (orange, strawberry, mint, lemon, vanilla, etc.), etc., and is formulated and used according to a conventional method. Further, if necessary, it may be coated with a coating agent (sucrose, gelatin, hydroxypropyl cellulose, hydroxypropyl methylcellulose phthalate, etc.), or may be coated with two or more layers. Further, if necessary, additives such as preservatives, antioxidants, colorants, and sweeteners that are commonly used can be added. The oral patch is manufactured according to a known method. For example, one or more active substances include excipients (lactose, mannitol, glucose, microcrystalline cellulose, colloidal silica, starch, etc.), binders (hydroxypropyl cellulose, polyvinylpyrrolidone, magnesium aluminometasilicate, etc.), disintegration. Agents (starch, L-hydroxypropyl cellulose, carboxymethyl cellulose, croscarmellose sodium, calcium fibrin glycolate, etc.), lubricants (steel) Magnesium arate, etc.), Adhesives (Hydroxypropyl Cellulose, Hydroxypropyl Methyl Cellulose, Carbopol, Carboxymethyl Cellulose, Polyvinyl Alcohol, Xanthan Gum, Guar Gum, etc.) Phosphate, citrate, silicate, glycine, glutamate, arginine, etc.) Stabilizers, solubilizers (polyethylene glycol, propylene glycol, glutamate, aspartic acid, etc.), flavors (orange, strawberry, mint, lemon, etc.) It is mixed with vanilla, etc.) and formulated according to a conventional method. Further, if necessary, it may be coated with a coating agent (sucrose, gelatin, hydroxypropyl cellulose, hydroxypropyl methylcellulose phthalate, etc.), or may be coated with two or more layers. Further, if necessary, additives such as preservatives, antioxidants, colorants, and sweeteners that are commonly used can be added. The orally rapidly disintegrating tablet is produced according to a known method. For example, one or more active substances as they are, or coating agents suitable for raw powder or granulated raw powder particles (ethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, acrylate copolymer, etc.), plasticizers (polyethylene) Active substances coated with glycol, triethyl citrate, etc.), excipients (lactoose, mannitol, glucose, microcrystalline cellulose, colloidal silica, starch, etc.), binders (hydroxypropyl cellulose, polyvinylpyrrolidone, metasilicic acid, etc.) Magnesium aluminate, etc.), disintegrant (starch, L-hydroxypropyl cellulose, carboxymethyl cellulose, sodium croscarmellose, calcium fibrin glycolate, etc.), lubricant (magnesium stearate, etc.), dispersion aid (glucose, fructose, etc.) , Mannitol, xylitol, erythritol, maltose, trehalose, phosphate, citrate, silicate, glycine, glutamate, arginine, etc.) Stabilizers, solubilizers (polyethylene glycol, propylene glycol, glutamate, aspartic acid, etc.), It is mixed with flavoring agents (orange, strawberry, mint, lemon, vanilla, etc.) and used by formulating it according to a conventional method. Further, if necessary, it may be coated with a coating agent (sucrose, gelatin, hydroxypropyl cellulose, hydroxypropyl methylcellulose phthalate, etc.), or may be coated with two or more layers. Further, if necessary, additives such as preservatives, antioxidants, colorants, and sweeteners that are commonly used can be added. Oral solutions for oral administration include pharmaceutically acceptable liquids, suspensions, emulsions, syrups, elixirs and the like. In such solutions, one or more active substances are dissolved, suspended or emulsified in commonly used diluents (such as purified water, ethanol or a mixture thereof). Further, this liquid agent may contain a wetting agent, a suspending agent, an emulsifier, a sweetening agent, a flavoring agent, a fragrance agent, a preservative, a buffering agent and the like. Dosage forms of external preparations for parenteral administration include, for example, ointments, gels, creams, poultices, patches, liniments, sprays, inhalants, sprays, aerosols, eye drops, and Includes nasal drops and the like. These contain one or more active substances and are manufactured by known methods or commonly used formulations. Ointments are manufactured according to known or commonly used formulations. For example, it is prepared by triturating or melting one or more active substances in a base. The ointment base is selected from known or commonly used ones. For example, higher fatty acids or higher fatty acid esters (adipic acid, myristic acid, palmitic acid, stearic acid, oleic acid, adipic acid ester, myristic acid ester, palmitic acid ester, stearic acid ester, oleic acid ester, etc.), waxes (mitsurou). , Whale wax, ceresin, etc.), surfactants (polyoxyethylene alkyl ether phosphate, etc.), higher alcohols (cetanol, stearyl alcohol, cetostearyl alcohol, etc.), silicon oil (dimethylpolysiloxane, etc.), hydrocarbons (, etc.) Hydrophilic vaseline, white vaseline, refined lanolin, liquid paraffin, etc.), glycols (ethylene glycol, diethylene glycol, propylene glycol, polyethylene glycol, macrogol, etc.), vegetable oil (glazed oil, olive oil, sesame oil, terepine oil, etc.), animal oil (mink) Oil, egg yolk oil, squalane, squalane, etc.), water, absorption enhancer, anti-fog agent, or a mixture of two or more. Further, it may contain a moisturizer, a preservative, a stabilizer, an antioxidant, a flavoring agent and the like. Gels are manufactured according to known or commonly used formulations. For example, it is prepared by melting one or more active substances in a base. The gel base is selected from known or commonly used ones. For example, lower alcohols (ethanol, isopropyl alcohol, etc.), gelling agents (carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, ethyl cellulose, etc.), neutralizers (triethanolamine, diisopropanolamine, etc.), surfactants (monosteare, etc.). (Polyethylene glycol acid acid, etc.), gums, water, absorption accelerators, anti-rash agents, etc. are used alone or in combination of two or more. Further, it may contain a preservative, an antioxidant, a flavoring agent and the like. Creams are manufactured according to known or commonly used formulations. For example, it is prepared by melting or emulsifying one or more active substances in a base. The cream base is selected from known or commonly used ones. For example, higher fatty acid esters, lower alcohols, hydrocarbons, polyhydric alcohols (propylene glycol, 1,3-butylene glycol, etc.), higher alcohols (2-hexyldecanol, cetanol, etc.), emulsifiers (polyoxyethylene alkyl ethers, fatty acids, etc.) Esters, etc.), water, absorption enhancer, anti-fog agent, alone or a mixture of two or more. Further, it may contain a preservative, an antioxidant, a flavoring agent and the like. Poultices are manufactured according to known or commonly used formulations. For example, it is produced by melting one or more active substances in a base, forming a kneaded product, and spreading and coating it on a support. The compress base is selected from known or commonly used ones. For example, thickeners (polyacrylic acid, polyvinylpyrrolidone, gum arabic, starch, gelatin, methyl cellulose, etc.), wetting agents (urea, glycerin, propylene glycol, etc.), fillers (kaolin, zinc oxide, talc, calcium, magnesium, etc.) ), Water, solubilizer, tackifier, anti-rash agent, alone or in combination of two or more. Further, it may contain a preservative, an antioxidant, a flavoring agent and the like. The patch is manufactured according to a known or commonly used formulation. For example, it is produced by melting one or more active substances in a base and spreading and coating it on a support. The base for the patch is selected from known or commonly used ones. For example, those selected from polymer bases, fats and oils, higher fatty acids, tackifiers, and anti-rash agents are used alone or in combination of two or more. Further, it may contain a preservative, an antioxidant, a flavoring agent and the like. Liniment agents are manufactured according to known or commonly used formulations. For example, one or more active substances are dissolved, suspended or dissolved in water, alcohol (ethanol, polyethylene glycol, etc.), higher fatty acids, glycerin, soap, emulsifier, suspending agent, etc. alone or in two or more. Prepared by emulsification. Further, it may contain a preservative, an antioxidant, a flavoring agent and the like. Sprays, inhalants, and sprays include buffers that provide isotonicity with stabilizers such as sodium bisulfite, in addition to commonly used diluents, such as sodium chloride, sodium citrate, or citric acid. It may contain such an isotonic agent. Injections for parenteral administration include solutions, suspensions, emulsions and solid injections used by dissolving or suspending in a solvent at the time of use. Injections are used by dissolving, suspending or emulsifying one or more active substances in a solvent. As the solvent, for example, distilled water for injection, physiological saline, vegetable oil, propylene glycol, polyethylene glycol, alcohols such as ethanol, and the like, and combinations thereof are used. Further, this injection may contain a stabilizer, a solubilizing agent (glutamic acid, aspartic acid, polysorbate 80 (registered trademark), etc.), a suspending agent, an emulsifier, a soothing agent, a buffering agent, a preservative, and the like. .. These are sterilized in the final step or manufactured by aseptic technique. It is also possible to produce a sterile solid preparation, for example, a lyophilized product, which is sterilized or dissolved in sterile distilled water for injection or other solvent before use. Inhalants for parenteral administration include aerosols, powders for inhalation or liquids for inhalation, and the liquids for inhalation are used by being dissolved or suspended in water or other suitable medium at the time of use. May be. These inhalants are produced according to known methods. For example, in the case of liquids for inhalation, preservatives (benzalkonium chloride, paraben, etc.), colorants, buffering agents (sodium phosphate, sodium acetate, etc.), isotonic agents (sodium chloride, concentrated glycerin, etc.) , Thickener (cariboxivinyl polymer, etc.), absorption enhancer, etc. are appropriately selected and prepared as necessary. In the case of powders for inhalation, lubricants (stearic acid and its salts, etc.), binders (starch, dextrin, etc.), excipients (lactose, cellulose, etc.), colorants, preservatives (benzalkonium chloride, etc.) , Paraben, etc.), absorption enhancer, etc. are appropriately selected and prepared as needed. A nebulizer (atomizer, nebulizer) is usually used when administering a liquid for inhalation, and an inhalation dispenser for powdered medicine is usually used when administering a powder for inhalation. Other compositions for parenteral administration include suppositories for rectal administration and pessaries for vaginal administration, which contain one or more active substances and are prescribed by conventional methods. In addition to commonly used diluents, the spray agent contains a buffer that provides isotonicity with a stabilizer such as sodium bisulfite, such as an isotonic agent such as sodium chloride, sodium citrate or citric acid. You may be doing it. Methods for producing sprays are described in detail, for example, in US Pat. No. 2,868,691 and US Pat. No. 3,095,355.

Fig. 1 (A) shows H-2L^dFlow cytometry showing PD-1 expression of specific 2C CTL clone and PD-L1 expression in PD-L1 expression stable transformant of P815 (mast cell type-derived cell line), (B) is PD-L1 Cytotoxic activity of 2C CTL cell line against expressed P815 cell line and anti-PD-L1 antibody (anti-PD-L1F (ab')₂It shows the effect of IgG) on cytotoxic activity. FIG. 2 shows the tumor growth and infiltration of the transplanted PD-L1-expressing P815 cell line in allogeneic mice. (A) is the tumor volume of the transplanted PD-L1-expressing P815 tumor (top) and the survival rate after transplantation (bottom), and (B) is the tissue staining of the transplanted PD-L1-expressing P815 tumor mass in allogeneic DBA / 2 mice. The image is (a is a 40-fold image showing the invasion of tumor cells into the abdominal wall and peritoneum, b is also a 400-fold image, c is a metastasis to the spleen, and d is a metastasis to the liver). FIG. 3 shows the in vivo effect of the anti-PD-L1 antibody on the tumor growth of the transplanted PD-L1 expressed P815 cell line in syngeneic mice. (A) is the in vivo effect of the anti-PD-L1 antibody on IFN-γ production from tumor-specific CD8 + T cells in the mouse, and (B) is the tumor volume of the transplanted PD-L1-expressing P815 tumor in the mouse (above). ) And the in vivo effect of the anti-PD-L1 antibody on the survival rate (bottom) (in the figure, is the control group (rat IgG administration group), is the anti-PD-L1 antibody (anti-PD-L1F (ab')). )₂IgG) administration group). Figure 4 shows PD-1 gene homozygous allogeneic mice (PD-1).^-/-) Suppresses the growth of PD-L1 expressed B16 melanoma. Figure 5 shows the in vivo effect of anti-PD-L1 antibody on tumor growth of transplanted myeloma cell lines in syngeneic mice (BALB / c) and the involvement of PD-1. (A) is flow cytometry showing PD-L1 expression in various myeloma cell lines, (B) is the in vivo effect of anti-PD-L1 antibody on the tumor volume of transplanted J558L tumor in the mouse, and (C) is wild type. And PD-1 gene deficiency PD-1^-/-A comparison of tumor growth of transplanted J558L tumors in allogeneic mice is shown. FIG. 6 shows PD-L1 expression on the vascular endothelium. (A) shows the expression of PD-L1 and PD-L2 in vascular endothelial cells of mouse heart. (B) shows histological staining to confirm PD-L1 expression in each mouse tissue. (a): Eyeball, (b): Submandibular gland, (c): Heart, (d): Lung, (e): Liver, (f): Kidney expression of PD-L1. In the figure, Ch indicates the choroid, CV indicates the central vein, Gl indicates the glomerulus, and Re indicates the retina. Each arrow indicates a vascular endothelial cell. Each stained image is a 40x magnified image. FIG. 7 shows PD-L1 expression in liver nonparenchymal cells. (A) shows ICAM-1 expression in mouse liver, and (B) shows PD-L1 expression (CV: central vein). FIG. 8 shows the phenotypes of cell surface molecules in Kupffer cells and perisinusoidal endothelial cells (LSEC). Figure 9 shows PD-1 gene homozygous mice (PD-1).^-/-) Or the phenotype of the cell surface molecule in CD4-positive T cells of wild-type mouse (wt). Figure 10 shows PD-1 gene homozygous mice (PD-1).^-/-) Or the phenotype of the cell surface molecule in CD8-positive T cells of wild-type mouse (wt). FIG. 11 shows the effect of PD-L1 on LNPC on T cell proliferation. (A) is PD-1^-/-The cell proliferation of mice and wt mice upon stimulation of naive T cells is shown. (B) is PD-1^-/-The effect of the anti-PD-L1 antibody on cell proliferation in co-culture of T cells already activated from mouse and wt mouse and LNPC is shown. FIG. 12 shows the effect of PD-L1 on LNPC on cytokine production. (A) is PD-1^-/-Cytokine production during naive T cell stimulation in mice and wt mice is shown. (B) is PD-1^-/-The effect of anti-PD-L1 antibody on cytokine production in co-culture of already activated T cells derived from mouse and wt mouse and LNPC is shown. (C) is PD-1 in co-culture with LNPC^-/-Shows cell division of activated T cells from mice and wt mice. FIG. 13 shows the involvement of PD-1 in the proliferation of T lymphocytes in virus-infected mouse liver. (A) is PD-1 on the 0th day after adenovirus infection, and (B) is PD-1 on the 7th day.^-/-It shows the proliferation of CD19-positive and CD3-positive lymphocyte cells in the liver and spleen of mice and wt mice. FIG. 14 shows the involvement of PD-1 in the proliferation of T lymphocytes in virus-infected mouse liver. (A) is PD-1 7 days after adenovirus infection^-/-It shows the proliferation of CD4 + and CD8 positive lymphocyte cells in the liver of mice and wt mice. (B) shows the proportion of various proliferative lymphocytes 7 days after infection. Figure 15 shows the involvement of PD-1 in viral infection. In the figure, (a) to (d) are PD-1 on days 0 and 7 after adenovirus infection.^-/-It is a tissue-stained image which shows the cell proliferation in the liver of a mouse and a wt mouse. (e) and (f) are PD-1 on the 7th day after adenovirus infection.^-/-It shows cell proliferation of CD4-positive and CD8-positive T cells in mice. FIG. 16 shows the involvement of PD-1 in viral infection. In the figure, (g) to (n) are PD-1 on days 0 and 7 after adenovirus infection.^-/-It is a hematoxylin & eosin tissue staining image of the liver of mouse and wt mouse. In the figure, (o) to (r) are PD-1 on days 0 and 7 after adenovirus infection.^-/-X-Gal stained image of liver of mouse and wt mouse. FIG. 17 shows the enhancing effect of each substance on cytotoxic activity. In the figure, (a) anti-mouse PD-1 antibody enhancing effect, (b) anti-mouse PD-L1 antibody enhancing effect, (c) mouse PD-1Fc enhancing effect, and (d) human PD-1Fc enhancing effect are shown. ..

Hereinafter, the present invention will be described in more detail with reference to examples, but these do not limit the scope of the present invention.

To prepare the mouse PD-L1 expression vector, the mouse PD-L1 cDNA (Journal of Experimental Medicine, 2000, Vol. 19, No. 7, p.1027-1034) was digested with the restriction enzyme EcoRI, and the expression vector pApuroXS ( The EMBO Journal, 1994, Vol. 13, No. 6, p.1341-1349) was inserted and linked. The prepared expression vector pApuroXS-PD-L1 was introduced into P815 cells by the electroporation method (360 V, 500 μF). Culture of P815 cells is FCS (10%), 2-mercaptoethanol (10)^-5M), it can be cultured in RPMI-1640 medium containing various antibiotics, but by subculturing the same cell line resistant to culture in a medium containing the antibiotic puromycin (Puromycin; 3 μg / ml). , A transformed P815 cell line that stably expresses mouse PD-L1 was obtained. The expression of PD-L1 was confirmed by flow cytometric analysis. H-2L in Fig. 1 (A)^dFlow cytometry showing PD-1 expression (i) of a specific 2C CTL clone and PD-L1 expression (ii) of P815 (mast cell line-derived cell line) in a PD-L1 expression-stable transformant is shown. A transformed B16 cell line (B16 / PD-L1) that stably expresses PD-L1 was obtained by the same method (see Fig. 1 (A) (iii) to (v)). Here, pEFBO Sneo-PD-L1 (Nucleic Acid Research, 1990, Vol. 18, No. 17, p.5322) prepared by the same method was used as the expression vector, and G418 (0.5 mg) was used for selective culture of cell lines. / ml) was used. The expression vector pVL1393 is obtained by digesting the cDNA encoding a protein in which a peptide tag (His-Tag) in which 6 histidines are arranged in tandem on the 3'end side of the full-length mouse PD-L1 cDNA is linked with the restriction enzymes EcoRI and NotI. (Product name: Purchased from Clontech) Inserted. Subsequently, this expression vector was introduced into SF9 insect cells (purchased from Invitrogen) to recover inclusion bodies. The inclusion body virus was infected by HiFive insect cells (purchased from Invitrogen) by culturing at 27 ° C for 2 days. Ni-Sepharose column chromatography was performed on a cell lysate lysed with a lysis buffer (Tris-HCl (50 mM, pH 7, 1% TritonX-100), EDTA (10 mM), NaCl (150 mM), various protease inhibitors). Purified PD-L1 protein as an antigen was obtained by treatment with. The dialyzed PD-L1 protein was immunized with a complete Freund's adjuvant in 8-week-old female Whister rats (purchased from SLC Japan), and a few days later, 2 × 10 collected from peripheral lymph nodes.⁸Cells were fused with the same number of SP2 / 0 cells using PEG1500 (purchased from Amersham). In addition, RPMI1640 medium (HAT (purchased from Sigma), Origen (10%, purchased from Igen), FCS (10%), 2-mercaptoethanol (10)^-5M), various antibiotics) were selected by culturing, and the presence of the produced antibody was confirmed by flow cytometric analysis. The hybridoma established thereby (international accession number: FERM BP-8396 recognized hybridoma) is transferred to Balb / C nu / nu mice, and the recovery solution from ascites is later purified by protein G sepharose column chromatography. As a result, a monoclonal antibody (1-111) against PD-L1 was obtained. The antibody used in flow cytometry and the like was biotinylated using Sulfo-NHS-LC-biotin (trade name: purchased from Pierce). In addition, an anti-human PD-1 antibody (monoclonal antibody produced from a hybridoma recognized by International Accession No .: FERM BP-8392) was prepared according to the same method. Cytotoxicity assay⁵¹It was performed by the Cr (chromium) release assay. 2C cells (Journal of Immunology, 1996, Vol. 157, No. 2, p.670-678) are derived from 2C transgenic B6 mice (H-2L).^dAllo-reactive cytotoxic T cells. 2C cells (E: effector) are shown in Fig. 1 (B).⁵¹Cr-labeled P815 cells (T: target) with () or three PD-L1 expressing P815 cell lines (P815 / PD-L1) (, , ) or with an additional 10 mg / ml rat anti-PD- L1F (ab')₂In the presence of IgG (), various E / T ratios are mixed and released in 4 hours.⁵¹The result of measuring Cr is shown. Anti-PD-L1 antibody (anti-PD-L1F (ab')₂) Restored the reduced cytotoxic activity of cytotoxic T lymphocytes. From these results, it is considered that inhibition of PD-1 and PD-L1 signals by inhibiting the function of PD-L1 can enhance cytotoxic activity against cancer cells.

1×10⁶P815 cells (n = 6) or P815 / PD-L1 cells (n = 6) of cells were transferred subcutaneously to syngeneic DBA / 2 mice, respectively, and tumor growth and mouse viability were evaluated. The results are shown in Fig. 2 (A). In the figure, is the P815 cell line transplant group, and and Δ are the PD-L1 expression P815 cell line transplant group. Furthermore, histological analysis of the group into which P815 / PD-L1 cells were transferred was performed. Figure 2 (B) shows a stained image obtained by fixing the tissue sections of the abdominal wall and peritoneal cavity of the mice 20 days after transfer with 10% formaldehyde, mounting them with paraffin, and staining them with hematoxylin and eosin. In the figure, a is a 40-fold image showing the infiltration of tumor cells into the abdominal wall and peritoneum, b is a 400-fold image, c is metastasis to the spleen, and d is metastasis to the liver. In the group transplanted with P815 cells, the proliferation of P815 cells was suppressed, and 30% survived at 6 to 7 weeks, whereas P815 cells expressing PD-L1 (P815 / PD-L1) were used. In the transplanted group, the growth of cancer cells was remarkable, and all cases died by 2 to 4 weeks (Fig. 2 (A)). P815 / PD-L1 infiltrated the peritoneal cavity and the abdominal cavity, and metastasis to the liver and spleen was observed (see Fig. 2 (B) a to d).

Cytotoxic T cell CTLs were prepared from mice immunized with P815 cells and 2 × 10⁶Number of CTL cells and 5x10⁶Only a number of P815 cells or P815 / PD-L1 cells, or anti-PD-L1F (ab')₂P815 / PD-L1 cells were mixed and cultured in the presence of IgG (10 mg / ml), and IFN-γ in the culture supernatant after 24 hours was measured with an ELISA kit (purchased from Bioscience). The results are shown in Fig. 3 (A). Also, in Fig. 3 (B), 3 × 10⁶Rat IgG () or anti-PD-L1F (ab') in allogeneic DBA / 2 mice (n = 10) subcutaneously transferred with the number of P815 / PD-L1 cells₂The results of intraperitoneal administration of IgG (0.1 mg / animal) () 1, 3, 5, and 7 days after cell transfer were performed to evaluate tumor growth and mouse survival. The anti-PD-L1 antibody restored IFN-γ production from cytotoxic T lymphocytes suppressed by P815 / PD-L1 (Fig. 3 (A)). Administration of anti-PD-L1 antibody suppressed cancer cell growth and showed a clear survival effect (Fig. 3 (B)). This result indicates that administration of anti-PD-L1 antibody is effective in treating cancer.

1×10⁶Subcutaneous transfer of the same number of B16 melanoma (n = 6) or B16 / PD-L1 cells (n = 6) into B6 mice, and the same number of B16 / PD-L1 cells in PD-1 transgenic B6 mice. (n = 5) and PD-1 gene homodeficient B6 mice (PD-1)^-/-(n = 4))) (Science, 2001, Vol. 291, No. 5502, p.319-332) was transferred, and each tumor growth was measured until the 25th day thereafter. The results are shown in Fig. 4.

2.5×10⁸Rat IgG or anti-PD-L1F (ab') in allogeneic Balb / C mice (n = 9) subcutaneously implanted with a number of J558L myeloma cells₂IgG (0.1 mg / animal) was intraperitoneally administered 3, 5 and 7 days after cell transfer to evaluate tumor growth (Fig. 5 (B)). Similarly, tumor growth in Balb / C (n = 4) was compared with PD-1 homozygous mice subcutaneously transferred with J558L myeloma cells (Fig. 5 (C)). Administration of anti-PD-L1 antibody causes proliferation of PD-L1 expressing J558 cancer cells (Fig. 5 (A) shows flow cytometry showing PD-L1 expression in various myeloma cell lines). It was suppressed (Fig. 5 (B)). In addition, the growth of transplanted cancer cells was completely inhibited in PD-1-deficient mice transplanted with J558 cells (Fig. 5 (C)). These results indicate that inhibition of PD-L1 or PD-1 is effective in treating cancer.

Vascular endothelial cells (hereinafter abbreviated as ECs) were obtained from mouse hearts by Mallery Berg's method (Journal Immunology Methods, 2000, Vol. 244, No. 1-2, p.205-215). Specifically, after digesting heart tissue with collagenase, preculture with mouse Ig, and further adding FITC-modified anti-CD31 antibody, the same modified anti-CD105 antibody, the same modified anti-isolectin B4 antibody, and anti-FITC beads. It was cultured. These vascular endothelial cells were purified by positive selection using Magnetic-activated cell-sorting separation columns (trade name: purchased from Miltenyi Biotec). The expression of PD-L1 and PD-L2 in the acquired vascular endothelial cells was confirmed by flow cytometry. The cells were labeled using an anti-PD-L1 antibody (antibody name: 1-111), an anti-PD-L2 antibody (antibody name: # 122), and a fluorescently labeled secondary antibody (Fig. 6 (Fig. 6 (Fig. 6)). A)). The analysis was performed with Facscalibur (device name: purchased from Becton Dickinson) using CellQuest software (purchased from Dickinson) at 10,000 events. Expression of PD-L1 or PD-L2 is indicated by an opening curve and control Ig is indicated by a filling curve. PD-L1 expression in each mouse tissue was confirmed by tissue staining. Mice were intravenously administered with 100 μl PBS in which 100 μg biotin-labeled anti-PD-L1 antibody (1-111) was dissolved 1 hour before each tissue sampling. Subsequently, 5 μm frozen sections were fixed with 4% paraformaldehyde (PFA) and stained with Streptavidin-FITC. In addition, each section was counterstained with Phalloidin (Fig. 6 (B), (a) eyeball, (b) submandibular gland, (c) heart, (d) lung, (e) liver, (f) kidney. In the figure, Ch indicates the choroid, CV indicates the central vein, Gl indicates the glomerulus, and Re indicates the liver. Each arrow indicates vascular endothelial cells. Each stained image is a 40-fold magnified image. It is.). PD-L1 was found in the vascular endothelium of the heart, lungs, kidneys, stomach, small intestine, submandibular glands, eyes, and liver. Expression in the liver was localized to hepatic sinusoidal capillaries.

PD-L1 expression in liver nonparenchymal cells (hereinafter abbreviated as LNPCs) was confirmed by tissue staining (Fig. 7 (A)) and flow cytometry (Fig. 7 (B)). For tissue staining, frozen sections of 5 μm liver fixed with 3% PFA were pretreated with rat serum and biotin-labeled anti-PD-L1 antibody (1-111) or biotin-labeled anti-ICAM-1 antibody (trade name: BD Pharmingen). The antibody reaction was carried out at room temperature for 1 hour (purchased from), and the biotin antibody was visualized by the tyramide signal amplification (TSA) fluorescence system (device name: purchased from Perkin Elmer Life Sciences) (Fig. 7 (A): Expression of ICAM-1, Fig. (B): Expression of PD-L1, CV: Central vein. Each stained image is a 40-fold magnified image). LNPCs are the pronase E method (Experimental Cell) It was isolated from mouse liver by Research, 1976, Vol. 99, p.444-449). Specifically, for LNPCs, the liver was refluxed in a pronase E solution (Merck), cultured, and separated by a density gradient centrifugation method. Kupffer Cells (CD54) in the cell suspension⁺, CD11b^{high high}) Is 20 to 25%, and hepatic sinusoidal endothelial cells (hereinafter abbreviated as LSECs) (CD54 +, CD11b)^{high high}) Is 75-80%. Kupfer cells and LSECs were double stained with FITC-labeled anti-CD11b antibody and each biotinylated monoclonal antibody against ICAM-1, PD-L1, B7-1, B7-2, followed by PE-labeled Streptavidin. .. Kupfer cells and LSECs are CD11b, respectively.^{high high}And CD11b^lowGated as a cell (Fig. 8). PD-L1 co-expressed ICAM-1, B7-1, and B7-2 in Kupfer cells, but its expression was weak in LSECs (Fig. 8).

PD-1 gene homozygous mouse (PD-1^-/-) Or wild-type C57BL / 6 mouse (wt) spleen and lymphoid tissue, purified naive T cells (purification degree 90% or more) by negative selection using T-cell enrichment column (trade name: purchased from Genzyme) did. The cells were activated by culturing with 10 μg / ml anti-CD3 monoclonal antibody (2C11) for 48 hours. Naive T cells activated by the above method were subjected to FITC-labeled anti-CD4 antibody or APC-labeled anti-CD8 antibody, PE-labeled anti-CD25 antibody, PE-labeled anti-CD44 antibody, PE-labeled anti-CD69 antibody, and PE-labeled anti-CD. Recognized by CTLA-4 antibody, biotin-labeled anti-B7-1 (CD80) antibody, biotin-labeled anti-B7-2 (CD86) antibody, anti-PD-1 antibody (antibody name: J43, international accession number FERM BP-8118) The expression of each molecule was analyzed by flow cytometry after double staining with an anti-PD-L1 antibody (1-111) and a monoclonal antibody produced from the hybridoma (Figs. 9 and 10). The international accession number FERM The hybrid doma identified by BP-8118 was deposited on May 30, 2001, at 1-1-1, Higashi, Tsukuba-shi, Japan, Central 6 (postal code 305-8566), National Institute of Advanced Industrial Science and Technology. It was deposited with the Center under the deposit number FERM P-18356 and transferred to the International Deposit on July 16, 2002.

PD-1 gene homozygous mouse (PD-1^-/-) Or the activation of naive T cells in wild-type mice (wt) was carried out by the method described in Example 8 above. The proliferation of the cells after activation was measured by the BrdU uptake method (Fig. 11 (A)). BrdU was added in the last 6 hours of 48 hours to label the cells, which was determined by measurement using a Proliferation ELISA kit (trade name: purchased from Roche). In addition, the amount of IFN-γ produced at this time was measured with an ELISA Kit (trade name: purchased from Genzyme) (Fig. 12 (A)). PD-1 gene homozygous mouse (PD-1^-/-) Or wild-type mouse (wt) -derived T cells were pre-activated by the method described in Example 8 above. Subsequently, the already activated T cells were further controlled with 30 μg / ml anti-PD-L1 antibody (1-111) in the presence or absence of mitomycin C-treated LNPCs from wild-type mice. The cells were cultured for 60 hours each in the presence or absence of rat IgG) and 20 μg / ml CTLA4-Ig (Genzyme) (controlled human IgG), and the proliferation of the cells for the last 12 hours was measured by the BrdU uptake method (BrdU uptake method). FIG. 11 (B). The amount of IFN-γ produced at 48 hours was also measured (Fig. 12 (B)). The amount of IFN-γ produced during activation of naive T cells is PD-1.^-/-No significant difference was observed between the mouse and the wild-type mouse. On the other hand, in already activated T cells, the amount of IFN-γ production of wild-type mouse-derived T cells is PD-1.^-/-It was significantly lower than that of the origin (Fig. 12). This suggests that the inhibitory effect of PD-1 on already activated T cells is higher than the effect on the activation of naive T cells. Activated T cells derived from wild-type mice did not show significant changes in T cell proliferation and IFN-γ production when co-cultured with LNPCs, but PD-1^-/-The derived activated T cells were found to have a significant increase in their cell proliferation by co-culture with LNPCs (Fig. 11 (B), Fig. 12 (B)). In addition, the addition of anti-PD-L1 antibody to the co-culture of activated T cells derived from wild-type mice and LNPCs was observed to increase the cell proliferation of T cells (Fig. 11 (B)). These results show that PD-1 or PD-L1 of LNPCs is involved in the suppression of activated T cells, and the lack of PD-1 or the inhibition of the interaction between PD-1 and PD-L1 is T. It indicates that it activates cells. PD-1 gene homozygous mouse (PD-1^-/-) Or wild-type mouse (wt) activated T cells labeled with 5 μM CFSE (5- (6) -carboxy-fluorescein diacetate succinimidyl diester) (trade name: purchased from Molecular probes) and co-located with LNPCs for 48 hours. It was cultured. The cell division at this time was determined by CFSE activity measurement using FACS (Fig. 12 (C)). The suppression of cell proliferation of activated T cells is due to the arrest of cell division, suggesting that PD-1 signal suppresses cell division of T cells (Fig. 12 (C)).

PD-1 gene homozygous mouse (PD-1^-/-) Or wild-type mice (wt) (3 / group) 10⁹-10¹⁰Mice were infected with adenovirus by intravenous administration of PFU (plaque-forming units) Ad-lacZ. Ad-lacZ used here is a type 5 adenovirus having a defect in the E1 and E3 regions and further carrying the lacZ gene, and after being propagated in 293 cells, cesium chloride density gradient centrifugation (Nucleic Acid). It was purified according to the description of Research, 1995, Vol. 234, No. 19, p.3816 ~ 3821). On the 0th or 7th day after infection, 0.5 mg BrdU (trade name: purchased from Sigma) was intravenously administered to the same mouse 1 hour before slaughter to suppress the collected spleen cells and lymphocytes in the liver. Double-labeled with BrdU antibody and anti-CD19 antibody or anti-CD3 antibody (Fig. 13). Furthermore, the cells 7 days after infection were double-labeled with anti-BrdU antibody, anti-CD19 antibody, anti-CD3 antibody, anti-CD4 antibody, and anti-CD8 antibody (Fig. 14 (B), each bar graph). Shows the percentage of BrdU-positive cells.). PD-1 infected with adenovirus^-/-In mouse livers, the proportion of proliferative (BrdU positive) lymphocytes (CD19 positive, CD3 positive, CD4 positive, CD8 positive) was increased compared to the livers of similarly infected wild-type mice. On the other hand, such a phenomenon was not observed in the spleen, suggesting that PD-1 inhibits the proliferation of T cells in inflamed tissues (Fig. 14 (B)).

PD-1 gene homozygous mouse (PD-1^-/-) Or wild-type mice (wt) (3 / group) 10⁹-10¹⁰PFU Ad-lacZ is intravenously administered to infect mice with adenovirus, and 0.5 mg BrdU (trade name: purchased from Sigma) is intravenously administered 1 hour before slaughter on the 0th or 7th day after infection. After administration, the collected liver sections were labeled with anti-BrdU antibody (Figs. 15 (a) to (d)), 20-fold magnified image). PD-1 gene homozygous mice 7 days after infection (PD-1)^-/-) Liver sections were double-labeled with anti-BrdU antibody and anti-CD4 antibody or anti-CD8 antibody (Figs. 15 (e), (f), 40-fold magnified image). In the liver of wild-type mice 30 days after infection, moderate local cell infiltration into sinusoidal capillaries and nonparenchymal regions was observed, but PD-1^-/-No symptoms indicating hepatitis were observed in the mice (Fig. 16 (h), (i) and (j), (n)). PD-1 gene homozygous mice 7 or 30 days after infection (PD-1)^-/-) Or wild-type mouse (wt) liver sections stained with hematoxylin & eosin (Fig. 16 (g)-(j), 20-fold magnified image, (k)-(n), 40-fold magnified image) and X-Gal staining was performed (Fig. 16 (o)-(r), 40x magnified image). In the livers of wild-type mice 7 and 30 days after infection, adenovirus infection as shown by X-Gal staining was observed, but PD-1^-/-In mice, the infection was largely eliminated by day 30 (Fig. 16 (o), (p) and (q), (r)). These results indicate that the PD-1 signal is involved in the elimination of the virus by inducing cell proliferation of effector T cells in inflamed tissues due to viral infection.

P-815 / PD-L1 cells in which mouse PD-L1 was forcibly expressed were seeded in a culture flask using a normal medium (hereinafter abbreviated as selective medium) containing 5 μg / mL puromycin (purchased from Sigma). , 37 ° C, 5% CO₂Incubate until 50% to 90% confluent under the condition of / 95% air. Mouse cytotoxic Tlymphocyte 2C cells were subcultured in normal medium for several days with MMC (Mitomycin C) treated P-815 cells and ConA-stimulated rat splenocyte culture supernatant. To the collected P-815 / PD-L1 cells, 3 μL of BATDA Reagent of DELFIA EuTDA Cytotoxicity Reagents (purchased from PerkinElmer) was added, and the cells were cultured for 15 minutes. In addition, it was washed with PBS. As 2C cells, cells on the 5th to 8th days, which were passaged by adding P-815 cells, were used. Anti-mouse PD-1 antibody (anti-mPD-1Ab (J43) in Fig. 17), anti-mouse PD-L1 antibody (anti-mPD-L1Ab (1-111) in Fig. 17), which are the test substances, 96 well of mouse PD-1Fc (mPD-1Fc in the figure), human PD-1Fc (hPD-1Fc in the figure), mouse IgG2aκ (ControlIg in the figure) or PBS 20 μL (10 ng / mL) was dispensed into the plate, and 50 μL of P-815 / PD-L1 cells or normal medium was added. In addition, 50 μL of 2C cells, normal medium or normal medium containing 1% Triton X100 was added. 50 μL of the supernatant of the wells supplemented with normal medium was collected for background and stored at 37 ° C until the other supernatants were collected. The remaining cells were cultured for 4 hours. Subsequently, the 96-well plate was centrifuged to collect the supernatant. 200 μL of DELFIA Europium Solution from Cytotoxicity Reagents (purchased from PerkinElmer) was added to the collected supernatant and shaken for 15 minutes. After shaking, time-resolved fluorescence measurement was performed with an ARVO sx multi-label counter (WALLAC). The supernatant of the well to which the normal medium containing 1% Triton X100 was added was set to high control, and the supernatant of the well to which the normal medium was added was set to low control. The composition of the evaluation group was the test substance, P-815 / PD-L1 cells and 2C cells, and the composition of the high control group was the normal medium containing PBS, P-815 / PD-L1 cells and 1% Triton X100, and the low control. The composition of the group is PBS, P-815 / PD-L1 cells and normal medium, the composition of the 2C cell control group is PBS, normal medium and 2C cells, and the composition of the background group is PBS, P-815 / PD- L1 cells and normal medium. The CTL activity (%) was calculated by the following formula. All values were obtained by subtracting the average value obtained in the background. CTL activity (%) = ([Evaluation group measurement]-[2C cell control group measurement]-[Low control group measurement]) ÷ ([High control group measurement]-[Low control group measurement]) × 100 Anti-PD-1 antibody, anti-PD-L1 antibody and PD-1Fc significantly enhanced CTL activity (Figs. 17 (a)-(d), in which E: Tratio is 2C cells and PD-L1. / P815 shows the mixing ratio of cells.).

C57BL / 6 mice with B16 melanoma cells transferred to the spleen were intraperitoneally administered with anti-mouse PD-1 monoclonal antibody every 2 days, and liver weight was measured 18 days after transfer to prevent cancer metastasis. The inhibitory effect of anti-PD-1 antibody was evaluated. Compared with the control group to which only control IgG was administered, the increase in liver weight was significantly suppressed in the anti-PD-1 antibody-administered group (liver weight / non-cancer cell transfer group: 1.3 g, control group: 6.8 g to anti-PD. -1 antibody administration group: reduced to 3.5 g). This suppression of weight gain indicates that it suppresses the metastasis of B16 melanoma cells.