CD4 and systemic lupus erythematosus: CD4+CD25+Foxp3+ Treg cells were upgraded in the spleen, thymus, and peripheral blood of lupus mice treated with IL-35, so that the CD4+CD25+Foxp3+ Treg/CD4+CD25− Teff ratio was obviously upregulated in all groups after IL-35 therapy, and the proportion of IL-10+ Bregs obviously increased with IL-35 treatment [42].