MCAM and musculoskeletal system disorder: Paucity is known about the role of CD146 in hematopoietic cells, although CD146 expression could identify a unique subset of CD3+CD4+ T-lymphocytes that may play an important role in the pathogenesis of various musculoskeletal diseases; however, its expression on activated T-cell populations as well as on a subset of murine NK cells was also reported [18, 19].