IL-10 inhibits macrophage activation and proliferation by distinct signaling mechanisms: evidence for Stat3-dependent and -independent pathways

Abstract

Interleukin-10 (IL-10) limits inflammatory responses by inhibiting macrophage activation. In macrophages, IL-10 activates Stat1 and Stat3. We characterized IL-10 responses of the J774 mouse macrophage cell line, and of J774 cells expressing wild-type hIL-10R, mutant hIL-10R lacking two membrane-distal tyrosines involved in recruitment of Stat3 (hIL-10R-TyrFF), a truncated Stat3 (DeltaStat3) which acts as a dominant negative, or an inducibly active Stat3-gyraseB chimera (Stat3-GyrB). A neutralizing anti-mIL-10R monoclonal antibody was generated to block the function of endogenous mIL-10R. IL-10 inhibited proliferation of J774 cells and of normal bone marrow-derived macrophages, but not J774 cells expressing hIL-10RTyrFF. Dimerization of Stat3-GyrB by coumermycin mimicked the effect of IL-10, and expression of DeltaStat3 blocked the anti-proliferative activity of IL-10. For macrophage de-activation responses, hIL10R-TyrFF could not mediate inhibition of lipopolysaccharide-induced TNFalpha, IL-1beta or CD86 expression, while DeltaStat3 did not interfere detectably with these IL-10 responses. Thus signals mediating both anti-proliferative and macrophage de-activation responses to IL-10 require the two membrane-distal tyrosines of IL-10R, but Stat3 appears to function only in the anti-proliferative response.

Immune Modulation and Prevention of Autoimmune Disease by Repeated Sequences from Parasites Linked to Self Antigens

“…The effect of cytokine blockade on the clinical course of EAE was monitored daily. The following monoclonal antibodies were used: anti-IL-10 receptor (αIL-10R) (clone 1B1.3a) (O'Farrell et al, 1998), anti-transforming growth factor beta (αTGF-β) (clone 1D11) (Dasch et al, 1989) and rat IgG1 isotype control (clone G1-113) (Sigma). αIL-10R and αTGF-β antibodies were produced at the Max Delbrück Center from hybridoma cell lines and purified on Protein G columns (Thermo Scientific-Pierce, Germany) followed by dialysis.…”

Post-traumatic inflammation following spinal cord injury

“…IL-10 is a potent anti-inflammatory cytokine that supresses the majority of microglial/ macrophage responses. 4,28,93 This cytokine blocks the activation of NF-kB and attenuates the synthesis of various cytokines, chemokines, and matrixproteases. With respect to the CNS, IL-10 reduces the TNF-a production by astrocytes as well as the antigen presentation by both astrocytes and microglia.…”

The Relative Contribution of IL-4 Receptor Signaling and IL-10 to Susceptibility toLeishmania major

“…Our initial results using the anti-IL-10 mAb (clone JES5-A) indicated that IL-10 production was not efficiently neutralized by this Ab in vivo (data not shown). Therefore, we explored IL-10 neutralization by weekly injections of an mAb to the IL-10R (clone 1B1.3a) (16), which has recently been shown to promote sterile cure following healing in L. major-infected C57BL/6 mice (18) and in L. donovani-infected mice (19). Six weeks following infection, the number of LV39 pms per milligram of tissue was decreased ϳ600-fold in the anti-IL-10R-treated BALB/c mice, although four of the six treated mice still harbored Ͼ10 4 /mg of tissue (Fig.…”