Interleukin 11 (IL-11) is a member of a family of human growth factors that includes human growth hormone, granulocyte colony-stimulating factor, and other growth factors. IL-11 is a thrombopoietic growth factor that directly stimulates the proliferation of hematopoietic stem cells and megakaryocyte progenitor cells and induces megakaryocyte maturation resulting in increased platelet production. It also promotes the proliferation of hepatocytes in response to liver damage. Binding to its receptor formed by IL6ST and either IL11RA1 or IL11RA2, It activates a signaling cascade that promotes cell proliferation. The signaling leads to the activation of intracellular protein kinases and the phosphorylation of STAT3.