Major Histocompatibility Complex I Flashcards
In adaptive immune system, for appropriate response to a foreign antigen what must happen and what happens in result of this?
Lymphocytes must recognise antigen
They then are stimulated to divide and differentiate
Antigen receptors B cells, how are they mediated?
Surface immunoglobulin
BCRbinds to native (unprocessed) antigen on pathogens
How are T cells mediated?
T cell receptor (TCR)
Presence of infected cells and foreign antigens can be detected by what?
T cells
Pathogen-derived peptides delivered to and presented at cell surface by specialised glycoproteins known as what?
Major Histocompatibilty Complex (MHC) molecules
MHC proteins are encoded in large cluster of genes on what chromosome?
6
In humans, what are MHC molecules also referred to as?
Human Leucocyte Antigens (HLA)
There are two MHC families, MHC class I and II, each containg three members. Name them
Class I- HLA-A, HLA-B, HLA-C
Class II- HLA-DP, HLA-DQ, HLA-DR
Where is MHC Class I expressed?
Expressed on all nucleated cells including leucocytes
Where is MHC Class I expressed?
Expressed only on leucocytes which present antigen to T cells i.e Antigen Presenting Cells
Where is MHC Class II expressed?
Expressed only on leucocytes which present antigen to T cells i.e Antigwn Presenting Cells
What does MHC restriction mean?
TCR will not recognise the same peptide bound to other MHC molecules nor will a different antigenic peptide bound to the same MHC
Individuals with certain HLA types are predisposed to certain diseases. What form of HLA type have Ankylosing Spondylitis (chronic inflammation of the spine)?
HLA-B27
Class I and II MHC proteins have related 3D-structures but different subunits. What are the different subunits?
Class I- Beta2 micro-globulin
Class II- Beta chain
MHC class I present peptides to what?
cytotoxic T cells (CD8+)
