Soluble interleukin 6 (IL-6) receptor and IL-6 levels in serum and synovial fluid of patients with different arthropathies.

Abstract

Unlike IL-6, sIL-6R is not produced at the site of inflammation and is not related to clinical or biological disease activity variables. Only in RA are both IL-6 and sIL-6R levels increased, suggesting that sIL-6R may reinforce the systemic effects of IL-6.