The main effects of IL-10 are Inhibition of IL-2 secretion by Th1 cells Downregulation of production of class II MHC molecules and cytokines (eg, IL-12) by monocytes, macrophages, and dendritic cells, thereby inhibiting Th1-cell differentiation Inhibition of T-cell proliferation Enhancement of B-cell differentiation Clinical relevance of IL-10 includes Possible suppression of pathogenic immune response in allergy and autoimmune disorders IL-11 is produced by bone marrow stromal cells The main effects of IL-11 are Promotion of pro-B and megakaryocyte differentiation Induction of acute phase reactants Clinical relevance of IL-11 includes Prevention of thrombocytopenia after myelosuppressive chemotherapy IL-12 is produced by B cells, dendritic cells, macrophages, and monocytes.