IS Major Histocompatibility Complex (MHC) Flashcards
major histocompatibility complex was originally referred to as?
Human Leukocyte Antigen
determine whether transplanted tissue is histocompatible and thus accepted or recognized as foreign or rejected
Major Histocompatibility Complex molecules
found on all nucleated cells in the body and play a pivotal role of development of both humoral and cellular immunity
Major Histocompatibility Complex
most polymorphic system found in humans
Major Histocompatibility Complex system
genes coding for MHC molecules are found in?
Chromosome 6
encodes glycoproteins expressed on the surface of all nucleated cells and are used for presentation of endogenous peptide antigens to CD8+ T cells. What MHC class is stated?
MHC Class I
encodes glycoproteins expressed on APC and are used for presentation of exogenous peptide antigens to CD4+ T cells. What MHC class is stated?
MHC Class II
encodes several different proteins with immune functions including complement proteins, cytokines, and tumor necrosis factor. What MHC class is stated?
MHC Class III
where is MHC class I located?
HLA-A, HLA-B, HLA-C
where is MHC class II located?
HLA-D
different forms of genes or alternate forms of gene
Polymorphism
> 2103 alleles
HLA-A
> 2605 alleles
HLA-B
1551 alleles
HLA-C
what is MHC Class I composed of?
a chain and b2-macroglobulin
how many times is the a chain folded into?
3
the binding site of MHC class I is able to hold peptides that are between?
8 and 11 amino acids
a3 region reacts with?
CD8 on cytotoxic T cells
what is MHC Class II composed of?
Heterodimers consisting of a and b chain
the binding site of MHC class II is able to hold peptides that are between?
13-18 amino acids
what allows the class II molecules to capture longer peptides that class I molecules?
peptide binding cleft being open
b2 region reacts with?
CD4 on helper T cells
where are class I molecules synthesized?
rough endoplasmic reticulum
if the CD8+ T cell produces cytokines if it recognizes the antigen as being foreign what will happen?
causes lysis of the entire cell
class I molecule is an (endogenous or exogenous) pathway of antigen presentation
endogenous
class II molecule is an (endogenous or exogenous) pathway of antigen presentation
exogenous
where are class II molecules synthesized?
rough endoplasmic reticulum with invariant chain
what is being gradually degraded once transported to endosomal compartment called CLIP?
invariant chain or li
what is the fragment called when invariant chain is gradually degraded when it is being transported to endosomal compartment?
class II invariant chain peptide or CLIP
clinical significance of MHC
tissue transplant, paternity testing, relevance to development of autoimmune diseases
