HLA-I is present on:: (A) All nucleated cells, (B) Only on cells of immune system, (C) Only on B cells, (D) Only on T cells
Answer is A. Ans. is 'a' i.e., All nucleated cells(Ref: Jawetz, 27th/e, p. 139)* HLA class I Ag - present on the surfaces of all nucleated cells.* HLA class II Ag - only on cells of immune system (macrophages, dendritic cells, activated T cells and B cells).