MHC class I represented on-

Ans. is 'b' i.e.. All nucleated cells [Ref: Robbin's 8th/e p. 192; Ananthanarayan 7th/e p. 130}o The histocompatibility antigens (human leukocyte antigens - HLA) are cell surface antigens that induce an immune response leading to rejection of allografts.o The principal physiologic function of the cell surface histocompatibility molecules is to bind peptide framents of foreign proteins for presentation to antigen specific T celts.o The histocompatibility antigens are encoded by a closely linked multiallelic cluster of genes - Major histocompatibility complex (MHC) or Human leukocyte antigens complex (HLA complex).MHCClass IClass 11O B cellso B ceilso Langerhan's cellso Langerhans's cellso Dendritic cellso Dendritic cellso Macrophageso MacrophagesoT-cellsoT cellso Epithelial cells of thymuso Epithelial cells of thymuso Neutrophils o Hepatocytes o Kidney o Brain o HLA complex of genes is located on the short arm of chromosome 6.o It consists of three separate clusters of genes :HLA Complex (MHC complex|Class 1Class 11Class IIIo Comprising A, B and C locio 'D" region - DR, DQ, DPComplement region encodeso Responsible foro Responsible foro C,&Cj# Graft rejection# Graft versus host responseo Properdin factor B# Cell mediated cyto lysis# Mixed leucocyte reactiono Heat shock proteino Found on the surface ofoFound only on cellso TNF - ot and iall nucleated cells andof the immune system platelets