4 VCAM-1 enhance RANKL induced osteoclast differentiation

Abstract

During orthodontic therapy, osteoclast precursors such as monocytes and macrophages migrate from vessels into the periodontium and then differentiate into osteoclasts, causing bone resorption. Vascular cell adhesion molecule-1 (VCAM-1) is bound to very late antigen-4 (VLA-4) which is a kind of α4 β1-integrin. It recruits monocytic osteoclast progenitors and elevates local osteoclast activity. We focused on how VCAM-1/α4 integrin mediates the differentiation into osteoclasts and found that it was through FAK. Neutralizing antibodies against integrin α4 effectively inhibited the differentiation into osteoclasts and the phosphorylation of FAK. These findings confirmed that VCAM-1 regulates the differentiation of bone into osteoclasts.