Abstract: The object of the present invention is to provide an antibody capable of immunologically and specifically binding to a folate receptor ? and a folate receptor ?. Specifically, the present invention relates to an antibody or a fragment thereof, in which the amino acid sequences of CDRH1, CDRH2, and CDRH3 of a heavy chain variable region (VH) are SEQ ID NOs: 2, 4, and 6, respectively, and the amino acid sequences of CDRL1, CDRL2, and CDRL3 of a light chain variable region (VL) are SEQ ID NOs: 10, 12, and 14, respectively.

Abstract: This invention relates to a pharmaceutical composition for inhibiting the growth and/or metastasis of invasive pancreatic cancer in a subject, comprising a molecular-targeted anticancer agent and a pharmaceutically acceptable carrier, wherein the molecular-targeted anticancer agent is a conjugate of a toxin or cytotoxic agent and an antibody or fragment thereof which immunologically and specifically binds to a cell-surface folate receptor ? (FR?) protein of an FR? (+) macrophage that exists around pancreatic cancer cells at the invasive front, and to a diagnostic agent and kit for determining the degree of malignancy of pancreatic cancer or the presence of invasive pancreatic cancer, characterized by determining that the cancer tissue is invasive and metastatic when FR? (+) macrophage is distributed around pancreatic cancer cells at the invasive front.

Abstract: The object of the present invention is to provide an antibody capable of immunologically and specifically binding to a folate receptor ? and a folate receptor ?. Specifically, the present invention relates to an antibody or a fragment thereof, in which the amino acid sequences of CDRH1, CDRH2, and CDRH3 of a heavy chain variable region (VH) are SEQ ID NOs: 2, 4, and 6, respectively, and the amino acid sequences of CDRL1, CDRL2, and CDRL3 of a light chain variable region (VL) are SEQ ID NOs: 10, 12, and 14, respectively.

Abstract: An object of the present invention is to provide a cartilage/bone destruction suppressor which can suppress the destruction of cartilage or bone seen in rheumatoid arthritis, osteoarthritis, bone metastasis of malignant tumor, or the like. The present invention relates to a cartilage or bone destruction suppressor comprising an antibody against folate receptor ? or a complex of the antibody and a biologically or chemically active substance.

Abstract: This invention relates to a pharmaceutical composition for inhibiting the growth and/or metastasis of invasive pancreatic cancer in a subject, comprising a molecular-targeted anticancer agent and a pharmaceutically acceptable carrier, wherein the molecular-targeted anticancer agent is a conjugate of a toxin or cytotoxic agent and an antibody or fragment thereof which immunologically and specifically binds to a cell-surface folate receptor ? (FR?) protein of an FR? (+) macrophage that exists around pancreatic cancer cells at the invasive front, and to a diagnostic agent and kit for determining the degree of malignancy of pancreatic cancer or the presence of invasive pancreatic cancer, characterized by determining that the cancer tissue is invasive and metastatic when FR? (+) macrophage is distributed around pancreatic cancer cells at the invasive front.

Abstract: It is intended to ameliorate arteriosclerosis or arteriosclerotic disease through a pharmacological mechanism that reduces the size of the arteriosclerotic lesion. The agent of the present invention comprises a complex comprising an antibody binding to folate receptor ? (FR?) and a cytotoxin or a cytotoxic agent conjugated with the antibody, or the antibody as an active ingredient.

Abstract: An objective of the present invention is to provide a therapeutic agent for treating rheumatoid arthritis, juvenile rheumatoid arthritis, macrophage activation syndrome, septicemia, and FR-? expressing leukemia, which induces apoptosis in activated macrophages and folate receptor beta (FR-?) expressing leukemia cells to specifically destroy these cells. An FR-? monoclonal antibody of the present invention is preferably an IgG-type monoclonal antibody which specifically reacts with a human-type FR-? antigen and is produced from a clone resulting from immunization with an FR-? expressing B300-19 cell. The FR-? monoclonal antibody of the present invention specifically reacts with the FR-? antigen of activated macrophages and FR-? expressing leukemia cells and a therapeutic agent of the present invention contains an FR-? antibody immunotoxin which causes apoptosis in activated macrophages and FR-? expressing leukemia cells, as an active ingredient.