IMMUNOSUPPRESSIVE EFFECTS OF 17-BETA-ESTRADIOL ON COLLAGEN-INDUCED ARTHRITIS IN MICE

The effects of oestradiol on collagen-induced arthritis (CIA) in ovari ectomized mice was studied. Oestradiol suppressed the incidence and se verity of arthritis, with a significant decrease in the CD4/CD8 ratio in lymphoid organs, followed by suppression of serum anti-type II coll agen antibodies. The CD4/CD8 ratio was first decreased in the thymus, and then in the spleen and regional lymph nodes, followed by a change in the serum antibody titre and the clinical manifestations of CIA. Th ese results suggest that oestradiol has an immunosuppressive effect on the progression of CIA through alteration of lymphocyte subsets.