ADAM12 and myeloid sarcoma: By RNA profiling, among 22 matrix metalloproteinases (MMPs) and 7 ADAM (a disintegrin and metalloproteinase) isoforms in EAE-induced mice, ADAM12 was found to be expressed almost exclusively by T cells.11 ADAM12 is a member of the ADAM family of MPs, which act as both proteases and signaling mediators, regulating cell fate.12 In EAE and MS, T cells and other leukocytes use MMPs to penetrate the BBB,13 increase cellular infiltration, and cause CNS pathology.