CNTF (Ciliary neurotrophic factor) is a polypeptide hormone whose actions appear to be restricted to the nervous system where it promotes neurotransmitter synthesis and neurite outgrowth in certain neuronal populations. This protein is a potent survival factor for neurons and oligodendrocytes and may be relevant in reducing tissue destruction during inflammatory attacks. CNTF protein is structurally related to leukemia inhibitory factor (LIF), interleukin-6 (IL-6), interleukin-11 (IL-11) and oncostatin M (OSM). It is localized in the cell nucleus subsequent to receptor binding. Recombinant human CNTF, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.