Integrin subunit beta 1 (ITGB1) (ITGB1)

Integrin subunit beta 1 (ITGB1), also known as CD29, is a transmembrane protein that functions as a primary receptor for Neural epidermal growth factor-like 1 (NELL-1) to mediate osteogenic signaling. NELL-1 is a secreted glycoprotein that plays a crucial role in bone development and regeneration; its interaction with ITGB1 on the surface of mesenchymal stem cells (MSCs) activates downstream pathways, including the Wnt/beta-catenin and MAPK/ERK cascades, which drive osteoblast differentiation and mineralization (Hasebe et al., 2012; Zhang et al., 2010). While ITGB1 has long been recognized as the mediator of these effects, recent studies have also identified Roundabout guidance receptor 2 (Robo2) as a high-affinity receptor for NELL-1, suggesting a more complex signaling mechanism (Lah et al., 2022). In clinical applications, recombinant human NELL-1 (rhNELL-1) is being developed as a therapeutic agent to promote bone growth in conditions such as spinal fusion and osteoporosis by targeting these receptors (Bone Biologics, 2023). However, because ITGB1 is ubiquitously expressed and involved in diverse processes like cell adhesion and immune response, therapeutic targeting must be carefully managed to avoid ectopic bone formation or systemic toxicity.

Other names

CD29Fibronectin receptor subunit betaVLA-4 subunit betaNELL-1 receptorNeural epidermal growth factor-like 1 receptorGlycoprotein IIa

Agonism of the receptor complex (primarily involving Integrin beta-1) by NELL-1 promotes osteoblast differentiation and bone formation via the activation of the Wnt/beta-catenin and MAPK/ERK signaling pathways (Hasebe et al., 2012; Zhang et al., 2010). Other drugs, such as monoclonal antibodies, may act as antagonists to inhibit cell adhesion or migration in inflammatory or neoplastic conditions.