CD160, also known as CD160 antigen, is a human natural killer (NK)-cell-activating receptor that is also expressed on T-cell subsets. It is a tumor-specific antigen known to mediate cellular activation signals in CLL, and is a novel target for therapeutic manipulation and monitoring of minimal residual disease. It was identified as a T cell coinhibitory molecule that interacts with the herpesvirus entry mediator (HVEM) on antigen-presenting cells to deliver a potent inhibitory signal to CD4(+) T cells. Recombinant human CD160, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.