LIF, a pleiotrophic factor, is identified in multiple cell types, including T cells, myelomonocytic lineages, fibroblasts, liver, heart and melanoma. LIF is capable of promoting long-term maintenance of embryonic stem cells by inhibiting spontaneous differentiation. In addition, LIF also have abilities including stimulation of differentiation of cholinergic nerves, the stimulation of acute phase protein synthesis by hepatocytes, and suppression of adipogenesis by supressing the lipoprotein lipase in adipocytes.