IL-6 effect on P-STAT3 and expression and release of IL-6 and its receptors. (A) Evaluation by western blot analysis of P-STAT3 and STAT3 in cell extracts after 1 hour of incubation with or without IL-6 at 10 ng/mL. β-Actin served as a loading control. P-STAT3 increases with IL-6 both in patients and in control participants. (B) Histograms of IL-6 levels in the plasma of patients and control participants measured by the ELISA test. (C) IL-6 mRNA expression and (D) secretion levels in patients (LGLs and LGL-depleted PBMCs, n = 27) and in control participants (CTLs and PBMCs, n = 18). (E) Histograms of IL-6Rα and gp130 mRNA expression levels in patients (LGLs) and in control participants (PBMCs). (F) Histograms of the secreted form of IL-6Rα in plasma measured by the ELISA test. All results are expressed as mean ± SE.