Antigen recognition by T cells Flashcards
How does the B cell receptor bind epitopes with high affinity?
through random somatic mutation and affinity maturation
How do T cell receptors bind complexes with moderate affinity?
random somatic mutation
What do B cell receptors bind?
conformational epitopes
What do T cell receptors bind?
peptide-MHC complexes
What is required for rearrangement of VDJ genes?
recombinase activating genes - RAG recombination system
Recombination of what genes creates the TCR alpha chain?
VJ
recombination of which genes creates the TCR beta chain?
VDJ
What area of the TCR is key for peptide:MHC recognition?
CDR3- determines specificty of hte TCR
What size of antigen can CD8 cells recognise?
8-9 amino acids long
What size of antigen can CD4 cells recognise?
variable length of peptide
What proteolytic enzymes are involved in antigen processing in the lysosyme?
cathepsins B, D, S, L
How is MHC class I II restricted antigen recognition imposed?
by the requirement of co-receptors e.g CD8 and CD4
What is the function of CD3 in the TCR?
doesn’t have antigen specificty but is used in signalling
In what area of the BCR and TCR does VDJ recomination generate somatic diversity?
CDR3
What are hte CDR1/2 areas of the TCR or BCR generated from?
germline
