Effects of interleukin-1 receptor antagonist on lymphocyte and macrophage of rats with collagen-induced arthritis

Objective:To investigate protections of interleukin-1 receptor antagonist (IL-lra) against collagen-induced arthritis (CIA) in rats. Methods: A CIA model was set up in SD rats by subcutaneous injection with type II collagen. The severity of arthritis was rated with arthritis scores. The examination of conA-and lipid polysaccharide (LPS)-induced splenocytes proliferation and interleukin-1 (IL-1) activities were conducted using a 3H-TdR intake method. Tumor necrosis factor alpha (TNF-α) and PGE_2 in the culture broth of macrophage (PMΦ) were quantified using radioimmunoassay. Results: The conA or LPS increased the level of T-and B-lymphocyte in 10 days after CIA in rats. The local inflammatory symptoms and B lymphocytes proliferation were reduced after subcutaneous injection with IL-lra at 7.5,30 and 120mg·kg~(-1)·d for 7 days, and T lymphocyte proliferation was suppressed when IL-lra at 30 and 120mg·kg~(-1)·d~(-1) was s. c. given in rats with CIA. The IL-1, TNF-α and PGR_2 levels in the PMΦ were inhibited by IL-1ra. Conclusion: IL-1ra inhibits the proliferation of lymphocytes and macrophage in the CIA rats.