MHC Class II proteins are expressed by:
(A) B-cells, dendritic cells and macrophages (B) Platelets (C) T-cells (D) All nucleated cells
(A) Answer- A. B-cells, dendritic cells and macrophagesMHC Class II proteins are expressed by all antigen-presenting cells, which include B-cells, follicular dendritic cells and macrophages. MHC Class I proteins are expressed by all nucleated cells, which excludes platelets and RBCsHLA class I antigens (A, B and C) are found on the surface of viually all nucleated cells- They ere the principal antigens involved in graft rejection and cell-mediated cytolysis.Class, I molecules may function as components of hormonal receptors. HLA class II antigens are more restricted in distribution, being found only on cells of the immune system macrophages, dendritic cells, activated T cells, and paicularly on B cells."