Cytokines play an important role in defining the fate of cells, such as proliferation, differentiation or death. Distinct responses of target cells to cytokines are determined by specific signal transduction events. The group of interleukin-6-type cytokines comprises also: interleukin-11 (IL-11), oncostatinM (OSM), leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF) and cardiotrophin-I (CT-I). IL-6-type cytokines use pl30 as a common b chain of their multimeric receptor complexes.