TGM2 and mastocytosis: Interestingly, it was shown that in children with mastocytosis, MCs may migrate to the skin and BM as the result of upregulation of CCL2/chemokine receptor 2 (CCR2) and vascular cell adhesion molecule (VCAM-1) and they may induce the expression/activation of transglutaminase 2 (TG2) [83].