CD27, as known as CD27 antigen, is a member of the TNF-receptor superfamily limited to cells of the lymphoid lineage, and exists as both a dimeric glycosylation on the cell surface and as a soluble protein in serum. As a T and B cell co-stimulatory molecule, the activity of CD27 is governed by its TNF-like ligand CD 70 on lymphocytes and dendritic cells. This protein plays a key role in regulating B-cell differentiation, activation and immunoglobulin synthesis. Recombinant human CD27, fused to hIgG-His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.