HLA complex is on chromosome -
Ans. is 'a' i.e., 6 HLA complexo 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 fragmentsofforeign proteins for presentation to antigen specific T cells.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).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 Class IClass IIClass HIo Comprising A, B and C locio 'D' region --> DR, DQ. DPComplement region encodeso Responsible foro Responsible foroC.&C.# Graft rejection# Graft versus hosto Properdin factor B# Cell mediated cytolysisresponse o Heat shock protein # Mixed leucocyte reactiono TNF - a and bo Found on the surface ofo Found only on cellso Enzyme 21 - hydroxylaseall nucleated cells andof the immune system platelets
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Immunology