Question

How does the MHC aid the adaptive immune system recognizing antigen? TT T Arial 3 (12pt) TEO's

Answer 1

MHC is the Major Histocompatibility Complex is a tightly linked cluster of genes present in every vertebrate species, the products of which play an important role in intercellular recognition and in discrimination between self and non - self.

The MHC genes are traditionally divided into three classes:

1. Class I MHC genes.

2. Class II MHC genes.

3. Class III MHC genes.

MHC class I and II genes encode the antigen-presenting MHC molecules.

MHC molecules and Antigen presentation

Both types of membrane glycoproteins (class I and II MHC) function as highly specialized antigen-presenting molecules. The class I and class II MHC molecules present antigen to T-cells. Antigen recognition is mediated by T-cell Antigen receptors. T-cell recognizes only peptides combined with MHC molecules. Class I molecules present processed endogenous antigen to CD8 T-cells. Class II molecules present processed exogenous antigen to CD4 T-cells. Exogenous antigens are those antigens that originate outside the organism or cell whereas endogenous antigens originate within the organism or cell.