CXCL8 and rheumatoid arthritis: Thus, although in general experimental stress does not seem to influence levels of certain cytokines and inflammatory markers in patients with rheumatic diseases (for example, sIL-2, IL-8, IL-10, IFN-γ, β-adrenoceptors), it does cause specific changes in CRP and TNF-α in patients with RA, changes in IL-4 in patients with SLE, and changes in IL-6 in patients with JIA.