ITGB7

Integrin beta-7 (ITGB7), a subunit of heterodimeric integrin receptors, pairs with α4 or αE subunits to form α4β7 and αEβ7 integrins. These proteins mediate lymphocyte trafficking and immune surveillance by binding to mucosal addressin cell adhesion molecule-1 (MAdCAM-1) and E-cadherin, respectively. α4β7 facilitates gut-specific homing of leukocytes, while αEβ7 promotes retention of intraepithelial lymphocytes in epithelial tissues. Both integrins activate intracellular signaling via Rho GTPases, focal adhesion kinase (FAK), and PI3K/Akt pathways, regulating cytoskeletal reorganization and immune cell activation. Dysregulation of ITGB7-linked pathways is implicated in inflammatory bowel disease (IBD), celiac disease, and cutaneous inflammatory disorders.

Targeting ITGB7-associated integrins has emerged as a therapeutic strategy. Vedolizumab, a humanized monoclonal antibody against α4β7, is approved for IBD treatment by blocking leukocyte infiltration into intestinal mucosa. Preclinical studies explore αEβ7 inhibition for eosinophilic esophagitis and allergic dermatitis. However, challenges remain in balancing tissue-specific immunosuppression with systemic toxicity. Recent efforts focus on small-molecule inhibitors of β7-mediated adhesion and allosteric modulators to fine-tune integrin activation. Genetic variants in ITGB7 are also linked to colorectal cancer metastasis, spurring interest in β7-targeted oncology therapies despite limited clinical progress.