JUP and Osteopenia: Liu et al. found that circulating ABs maintain the homeostasis of MSCs and ameliorate osteopenia.34 MSCs-derived ABs alleviated Pg-LPS induced inflammatory responses of macrophages and regulated osteoclast formation.40 Osteocyte-derived ABs are capable of initiating de novo osteoclastic bone resorption.41,42 The role of ABs in bone homeostasis needs to be further investigated.