Question

Please explain this

•Class I MHC Gene

•Glycoprotein expressed on all nucleated cells.

•Major function to present processed Ags and T C.

•Found in regions A, B, and C (K and D in mice).

•Class II MHC Gene

•Glycoprotein expressed on Macrophages, B-cells, DC’s.

•Major function to present Ags to T H.

•Found in regions DR, DP, and DQ (IA and IE in mice)

•Class III MHC Gene

•Products that include secreted proteins that have immune functions.

•Ex) Complement system.

Answer 1

Class I MHC (Major Histicompatibility Complex) gene encodes for a glycoprotein which is expressed on the cell surface of all nucleated cell. They present processed antigen to the cytotoxic T cell (T_c cell). In human the gene is found in A, B and C regions of genome. In mice, it is found in K and D regions.

Class II MHC gene encodes for a glycoprotein which is expressed on Macrophages, B - lymphocyte and dendritic cells (DCs). They present processed antigen to helper T cells (T_H cell). In human the gene is found DR, DP and DQ regions of genome. In mice it is found in IA and IE regions.

Class III MHC genes encode the products like secreted proteins such as C3 and C4, which have immune function in complement system.