Lair1, as known as leukocyte-associated immunoglobulin-like receptor 1 isoform a, is an inhibitory receptor of the lg superfamily that is related to inhibitory members of KIR and ILT/CD85 families. This protein is well expressed NK cells, T cells, B cells, monocytes, macrophages, immature neutrophils, dendritic cells and most thymocytes. Also, it functions as an inhibitory receptor not only on NK cells, but on human T cells. Recombinant mouse Lair1, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.