Purified anti-human Integrin alpha9beta1

Integrin alpha9beta1 is a transmembrane protein belonging to the integrin family. It is widely expressed in airway epithelium, different types of muscle cells, and hepatocytes. In the hematopoietic system, integrin alpha9beta1 is highly expressed on human neutrophils and at low level on monocytes. Multiple ligands have been identified for this integrin including the inducible endothelial counter-receptor, vascular cell adhesion molecule-1 (VCAM-1), the extracellular matrix proteins tenascin C and osteopontin, some members of ADAMs family, coagulation factor XIII, and von Willebrand factor. It has been reported that binding of the alpha9 cytoplasmic domain to spermidine/spermine N(1)-acetyltransferase (SSAT) mediates alpha9beta1 enhancement of cell migration, mediates adhesion to the extracellular matrix proteins, and is involved in G-CSF signaling. More recently, integrin alpha9beta1 was found on hematopoietic stem and progenitor cells to mediate stem cells adhesion, proliferation, and differentiation.