VARIATION OF LYMPHOCYTES IN PERIPHERAL-BLOOD AND BONE-MARROW IN COLLAGEN-INDUCED ARTHRITIS

Collagen-induced arthritis(CIA) was found to be useful as an animal mo del to investigate the mechanism by which rheumatoid arthritis is deve loped. We therefore studied variations of T and B lymphocytes in perip heral blood and bone marrow in order to ascertain the importance of T and B lymphocytes in the development of CIA. T lymphocyte, which is co nsidered to be associated with the onset and deterioration of CIA, was not changed during the course of CIA, whereas B lymphocyte, which pro duces anti-type II collagen andtibody regarded as an indispensable fac tor in CIA induction, was significantly decreased in peripheral blood and bone marrow at 10 days after the 2nd immunization when arthritis w as able to be detected. In bone marrow, although two cell populations of Ly5/B220-positive cells were detected, only the cell population wit h lower fluorescence intensity was decreased transiently. These result s suggest that B lymphocyte in both bone marrow and peripheral blood i s intimately involved in the course of CIA.