Major Histocompatiblility complex Flashcards
In adaptive humoral (anti-body mediated) immunity what is the function, response to, and major proteins for battle
blocks infection via elimination of extracellular microbes, extracellular microbes, B lymphocytes
In adaptive (cell mediated) immunity what is the function, response to, and major proteins for battle
activate macrophages to kill phagocytosed microbes/kill infected cells and eliminate reservoirs of infection, intracelluar microbes, T lymphocytes
What is the function of antigen presenting cells (APCs)
Capture, process and present antigen to T lymphocytes
What are the types of APCs
Dendritic cells, macrophages, and B lymphocytes
What is the function of APCs
naive T cell activation leads to differentiation into effector T cells, effector T cell activation leads to activation of macrophages and B cells (kill pathogen or secrete antibodies)
What is the most effective APC to a naive T cell, result
Dendritic cells, activates into differentiated T cells
HLA polymorphism
multiple alleles caused from mutations
HLA haplotype
The particular combination of MHC alleles present
HLA codominance
Equal expression of both materal and paternal genes are expressed equally
What are the the structures present in all MHCs
extracellular peptide binding cleft (binding peptide), Immunoglobulin (Ig) like domain (bind T cell corecptor), transmembrane cytoplasmic domain (anchors MHC to cell)
What is the type of cleft formed in MHC class 1
alpha chain only
For MHC class 1 the Ig-like domain binds what, what would be the function of the bound cell
CD8+ cytotoxic T cells, kill cells infected with intracellular microbes
T/F: MHC class 1 is present on all nucleated cells
True
What is the type of cleft formed in MHC class 2
alpha chain and beta chain
For MHC class 2 the Ig-like domain binds what, what is the function of the bound cell
CD4+ helper T cells, activate macrohpages to eliminate phagocytosed extracellular microbes/activate B lymphocytes to make antibodies that also eliminate microbes
What are the five steps that occur in Class 1 Pathway of antigen presentation
1) Production of antigenic proteins within cytosol 2) Proteolytic Digestion of Cytosolic protiens 3) Transport peptides from the cytosol to the Endoplasmic Reticulum Step 4) Assembly of Peptide -MHC Class 1 Complexes in the Endoplasmic Reticulum 5)Surface expression of Peptide MHC Class 1 complexes
In step 1 of Class 1 pathway of antigen presentation where is the source of the peptide presenteted
viruses and microbes
In Step 2 of Class 1 pathway of antigen presentation what is the enzyme that generates the peptides through digestion, how
proteasomes, proteins are ubiqutinated causing marks that leads to degradation
In Step 3 of Class 1 pathway of antigen presentation where is the MHC 1 synthesized at, what transports the peptides to the ER
Endoplasmic Reticulum, Transporter Associated with Antigen Processing (TAP)
T/F: TAP is not dependant on ATP
False: TAP is an active transport protein
In Step 4 of Class 1 pathway of antigen presentation what protein works with TAP to bring together MHC 1 and peptide
Tapasin, once released from tapasin it the whole complex and exit the ER
In Step 5 of Class 1 pathway of antigen presentation what moves the complex outside the cell,
exocytotic vesicles move stable complexes to the surface,
What are the five steps for MHC class 2 pathway of antigen presentation
1) Generation of Vesicular proteins 2) Proteolytic digestion of proteins in vesicles 3) Biosynthesis and Transport of Class 2 MHC molecules to endosomes 4) Association of processed peptides with class 2 MHC molecules in vesicles 5) Expression of MHC 2 complex on cell surface
