Antibodies and assays for detection of folate receptor 1

An antibody or antigen-binding fragment thereof that specifically binds to an epitope of FOLR1, wherein the antibody or antigen-binding fragment thereof comprises the VH CDR1-3 and VL CDR1-3 polypeptide sequences that are selected from the group consisting of: (a) SEQ ID NO: 3-8, respectively; (b) SEQ ID NO: 9-14, respectively; (c) SEQ ID NO: 15-20, respectively; (d) SEQ ID NO: 21-26, respectively; (e) SEQ ID NO: 3-5 and SEQ ID NO: 59, 7 and 8, respectively; (f) SEQ ID NO: 3, 60 and 5 and SEQ ID NO: 6-8, respectively; (g) SEQ ID NO: 3, 61 and 5 and SEQ ID NO: 6-8, respectively; (h) SEQ ID NO: 3, 60 and 5 and SEQ ID NO: 59, 7 and 8, respectively; and (i) SEQ ID NO: 3, 61 and 5 and SEQ ID NO: 59, 7 and 8, respectively.