ITGB2 and age-related macular degeneration: Other genes with significant up-regulation in MR in late AMD include the anaphylatoxin receptors, C3AR1, C5AR1 and C5AR2 (15-24-fold), the integrins ITGAM, ITGAX, ITGB2 (3-20-fold), and the adhesion molecule CD93 (20-fold).