CD5, as known as T-cell surface glycoprotein CD5, is a transmembrane glycoprotein in the scavenger receptor superfamily. This protein was found expressed in small lymphocytic lymphoma, hairy cell leukemia and mantle cell lymphoma cells. CD5 expression on developing thymocytes is positively regulated by signaling through the T cell antigen receptor and is up-regulated peripheral CD4+ cell. Also, its Signaling inhibits the generation of regulatory T cells but promotes the development of Th17 cells. Recombinant human CD5, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.