Recombinant Human Integrin alpha 4 beta 1/VLA-4 Protein (Flag & His)

Measured by functional ELISA. Immobilized recombinant VLA-4 binds soluble VCAM-1 and the CS-1 fibronectin fragment with EC50 values in the ng/mL range; binding is blocked by natalizumab-class antibodies.

Integrin alpha-4 beta-1 (VLA-4, CD49d/CD29) is the principal adhesion receptor by which leukocytes arrest on activated vascular endothelium, binding VCAM-1 and the CS-1 splice segment of fibronectin during inflammation. Its blockade with natalizumab proved the therapeutic power of leukocyte-trafficking control in multiple sclerosis and Crohn's disease, and VLA-4 biology remains central to immunology, hematopoiesis and leukemia-stromal adhesion research. Because integrin ligand recognition depends on the native α/β heterodimer with correct conformational state, this mammalian-expressed ectodomain heterodimer is the appropriate reagent for ligand-blocking assays, anti-integrin screening and adhesion biology.