Difference between MHC class I and MHC class II proteins (MHC 1 vs MHC 2)

Major histocompatibility complex (MHC) or Human Leukocyte Antigen (HLA)complex consists of genes encoding cell surface glycoproteins that are required for antigen presentation to T cells and also responsible for rapid graft rejection.The acceptance or rejection of transplant is controlled by a set of genes in the recipient’s body which is called as Major histocompatibility complex (MHC) or Human Leukocyte Antigen (HLA) complex in humans. 

Difference between MHC Class I and MHC Class II proteins

Difference between:

MHC Class I and MHC Class II proteins

	MHC class I proteins MHC class I	MHC class II proteins MHC class II
1	Present on the surface of all nucleated cells	Present on the surface of antigen presenting cells such as macrophages, B cells, dendritic cells etc.
2	Mainly interact with cytotoxic T cells	Mainly interact with helper T cells
3	Encoded by HLA-A, HLA-B and HLA-C genes	Encoded by HLA-D genes.
4	Consists of 2 non identical chains, a long alpha chain and a short beta chain	Consists of 2 roughly identical chains, an alpha chain and a beta chain
5	Alpha chain is coded on MHC locus of chromosome 6, whereas beta chain is encoded on chromosome 15.	Both chains are coded on MHC locus of chromosome 6
6	Responsible for graft rejection and clearance of endogenous antigens	Responsible for graft rejection and clearance of exogenous antigens