ICAM1, also known as intercellular adhesion molecule 1, belongs to the ICAM proteins. The proteins are ligands for the leukocyte adhesion protein LFA-1 (integrin alpha-L/beta-2). During leukocyte trans-endothelial migration, ICAM1 engagement promotes the assembly of endothelial apical cups through ARHGEF26/SGEF and RHOG activation. Recombinant mouse ICAM1, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.