Major histocompatibility complex MHC

The human leucocyte antigen (HLA) system is the general name of a group of genes in the human major histocompatibility complex (MHC) region on human chromosome 6 (mouse chromosome 17) that encodes the cell-surface antigen-presenting proteins. 

Group of transmembrane proteins engaged in the presentation of small peptide fragments to T-cells. Two classes of Major histocompatibility complex (MHC) molecules exist both of which are encoded by a highly polymorphic gene cluster. MHC class I and class II proteins present peptide fragments to CD8+ and CD4+ T-cells, respectively. The human MHC is also known as HLA, the murine MHC as H-2 complex. 

An unknown antigen presented by the major histocompatibility complex (MHC) class II molecules causes T cells to become autoreactive (Fig. 26-1). Once activated, T cells penetrate the... 

The T-lymphocyte receptor (TCR) is involved in detection of foreign antigens, presented together with the major histocompatibility complex (MHC). Subsequendy, it regulates the clonal expansion of T cells. 

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