The regulation of regulation: interleukin‐10 increases CD4+ CD25+ regulatory T cells but impairs their immunosuppressive activity in murine models with schistosomiasis japonica or asthma. Issue 1 (21st September 2017) - He, Lei
Summary: CD4 + CD25 + Foxp3 + regulatory T (Treg) cells play an important role in maintaining immune homeostasis. Interleukin‐10 (IL‐10), a cytokine with anti‐inflammatory capacities, also has a critical role in controlling immune responses. In addition, it is well known that production of IL‐10 is one of the suppression mechanisms of Treg cells. However, the action of IL‐10 on Treg cells themselves remains insufficiently understood. In this study, by using a Schistosoma japonicum ‐infected murine model, we show that the elevated IL‐10 contributed to Treg cell induction but impaired their immunosuppressive function. Our investigations further suggest that this may relate to the up‐regulation of serum transforming growth factor (TGF‐ β ) level but the decrease in membrane‐bound TGF‐ β of Treg cells by IL‐10 during S. japonicum infection. In addition, similar IL‐10‐mediated regulation on Treg cells was also confirmed in the murine model of asthma. In general, our findings identify a previously unrecognized opposing regulation of IL‐10 on Treg cells and provide a deep insight into the precise regulation in immune responses. Abstract : Interleukin‐10 (IL‐10) has bidirectional regulatory roles in Treg cells. Elevated IL‐10 contributes to Treg cell induction but impairs their immunosuppressive function.