CCL2 and rheumatoid arthritis: Comparison of basal secretory activity of the same type of adipose tissue between the study patients’ groups revealed that OA ScAT produced more pro-inflammatory (TNF and CCL2/MCP-1) as well as anti-inflammatory (IL-1Ra) factors than RA ScAT, except TGFβ which was secreted in larger quantity by rheumatoid tissue (Table 2).