LAIR1 Protein, Human (HEK293, His-Avi)

The LAIR1 Protein serves as an inhibitory receptor, exerting a constitutive negative regulatory influence on the cytolytic function of natural killer (NK) cells, B-cells, and T-cells. Upon activation through tyrosine phosphorylation, it recruits and activates phosphatases PTPN6 and PTPN11. LAIR1 also dampens the increase in intracellular calcium triggered by B-cell receptor ligation. Beyond its dependency on SH2-containing phosphatases, it independently modulates cytokine production in CD4+ T-cells, suppressing IL2 and IFNG while promoting the secretion of transforming growth factor beta. Additionally, LAIR1 down-regulates IgG and IgE production in B-cells and hinders the secretion of IL8, IL10, and TNF. In myeloid leukemia cell lines, LAIR1 inhibits proliferation, induces apoptosis, and prevents nuclear translocation of NF-kappa-B p65 subunit/RELA, along with the phosphorylation of I-kappa-B alpha/CHUK. Moreover, LAIR1 inhibits the differentiation of peripheral blood precursors into dendritic cells. It interacts with the SH2 domains of tyrosine-protein phosphatases PTPN6 and PTPN11, with the interaction with PTPN6 being constitutive. Furthermore, LAIR1 binds with high affinity to extracellular matrix collagens, highlighting the functional importance of this interaction.