LAIR1 Protein, Mouse (HEK293, mFc)

The LAIR1 protein operates as an inhibitory receptor, constitutively exerting a negative regulatory influence on the cytolytic function of natural killer (NK) cells, B-cells, and T-cells. Upon activation through tyrosine phosphorylation, LAIR1 recruits and activates phosphatases PTPN6 and PTPN11, leading to downstream inhibitory effects. Notably, it diminishes the increase in intracellular calcium triggered by B-cell receptor ligation. Beyond its role with SH2-containing phosphatases, LAIR1 independently modulates cytokine production in CD4+ T-cells, down-regulating IL2 and IFNG while inducing the secretion of transforming growth factor beta. It further regulates IgG and IgE production in B-cells, as well as the secretion of IL8, IL10, and TNF. LAIR1's impact extends to inhibiting proliferation, inducing apoptosis in myeloid leukemia cell lines, preventing nuclear translocation of NF-kappa-B p65 subunit/RELA, and inhibiting the phosphorylation of I-kappa-B alpha/CHUK in these cells. Moreover, it hinders the differentiation of peripheral blood precursors into dendritic cells. Interaction-wise, LAIR1 associates with the SH2 domains of tyrosine-protein phosphatases PTPN6 and PTPN11 constitutively and binds with high affinity to extracellular matrix collagens, a functionally significant interaction.