The role played by Major Histocompatibility Complex-1 and 2 is to?

Ans. (c) Present antigens for recognition by T cell antigen receptors Ref. Ananthanarayan 9/e, p 142; Greenwood 18/e, p 106 Both Class I and Class II antigen are involved in presentation of processed antigen on microphage and other accessary cells to T-cell. Cytotoxic T-cell recognize Class I MHC antigen on target cells Helper T cell can accept antigens presented by macrophages/dendritic cells only when they bear some Class II MHC molecules MHC Class I molecules consist of two non covalently associated polypeptide chains A, B, C. Present on all human nucleated cells except neurons MHC Class II Molecules: are composed of two chains DP, DQ and DR. Found on immune cells (dendritis cells, macrophages, monocytes and activated T lymphocytes MHC Class III genes- They are grouped together in a region between D and B.