MAJOR HISTOCOMPATIBILITY COMPLEX (MHC)

 

INTRODUCTION: By virtue of genetic make-up, every individual has unique antigens on the cell surfaces. Some of these are called as histocompatibility (histo: tissue) antigens. These are responsible for determining whether one tissue is compatible with another. In human beings these antigens are called as human leukocyte antigens (HLA). Expression of histocompatibility antigens is controlled by genes or groups of genes (loci) located close together (linked) on the same chromosomal strand. This segment of chromosome is called major histocompatibility complex, or MHC.

LINK IN HUMAN GENES: In humans MHC is called as HLA complex and is located on chromosome 6. This is large, complex genetic region that controls not only the exchange of tissues but also diverse cellular interactions of human cells, production of certain serum proteins, and production of few cytokines and enzymes.  Certain HLA antigens are also related to increased susceptibility to specific diseases. With the help of standard antisera, HLA types of an individual can be ascertained. An important medical application of HLA typing is transplantation where the donor and the recipient must be matched. Every individual will have a unique pattern of HLA type. The existence of HLA antigens in humans denotes the presence of a system which recognises these as self and does not reject these.

RELATED;

1.  IMMUNITY   

2.  AUTOIMMUNITY 

3.  AUTOIMMUNE DISEASE

4.  MEDICAL MICROBIOLOGY 

REFERENCES