Effect of Soluble Interleukin-6 Receptor on Interleukin-6 Synthesis in Human Skin Fibroblasts

Abstract In this study the ability of soluble interleukin-6 receptor (sIL-6R) to stimulate interleukin-6 (IL-6) synthesis in human fibroblasts is described. It was found that sIL-6R, in combination with endogenous or exogenous IL-6, markedly upregulated IL-6 synthesis. These data suggest that increased IL-6 production after stimulation by either interleukin-1 or tumor necrosis factor-α would result in complex formation with sIL-6R, rapid uptake, and further synthesis of this cytokine. Furthermore, it would explain the decrease in sIL-6R plasma levels observed in patients suffering from sepsis.