Immunology - 18 Flashcards
Where does MHC class I peptide loading occur?
Rough ER
Where does the MHC get the peptides that it eventually presents?
From phagocytosis
For MHC Class I, the peptides displayed are derived from (exogenous or endogenous) antigens?
Endogenous (proteins that are made inside the cell i.e. intracellular pathogens, but can also be host proteins so the T cells (CTL) has to determine if it is self or not)
What does an MHC class II molecule allow the T helper to see?
What is going on outside of the cell
Where does peptide loading occur in MHC Class I and II?
Class I - in the ER
Class II - inside vesicles that contain pathogens
What kind of antigen does class I MHC present?
Host, protein, etc.(Endogenous antigens)
What kind of antigen does class II MHC present?
Pathogenic (exogenous)
What do T cells do when they see MHC class II?
They secrete cytokines and help in the immune response
What is an antigen?
Something that is bound by an antibody or T cell receptor
Are all parts of an antigen an epitope?
No
Are all epitopes antigens?
Yes
