<prompt> True about MHCTransplantation reactionAutoimmune diseaseImmunosuppressionInvolved in T cell function  <response>: Ref Harrison 16e p1930; Robbins 7e p204_ 205 Also involved in autoimmune disease, involved T cell function MHC class II molecules are a class of major histocompatibility complex MHC molecules normally found only on professional antigen-presenting cells such as dendritic cells, mononuclear phagocytes, some endothelial cells, thymic epithelial cells, and B cells. Thesecells are impoant in initiating immune responses. 