2.5 Flashcards
T cells express ___ that recognize peptides displayed by MHC molecules
T cell receptor (TCR)
TCR on each T cell clone is specific for a ___
distinct peptide
which is the difference between the receptors of the innate and adaptive immunity?
a - both are clonal
b - the receptors of the innate immunity are clonal
c - the receptors of the adaptive immunity are clonal
d - the receptors of the adaptive immunity are not antigen specific
e - the receptors of the innate immunity are antigen specific
c - the receptors of the adaptive immunity are clonal
membrane-bound heterodimeric proteins are composed of alpha and beta chains with ___ and __ regions
- variable
- constant
the TCR binding site has variable domains of alpha chains for ___
MHC class I
the TCR binding site has variable domains of alpha and beta chains for ___
MHC class II
the TCR recognizes ___
processed antigen
how is the diversity of TCR generated?
recombination of V, D, J gene segments
____ of gene segments accounts for diversity of TCR gene loci
somatic recombination
recombination of TCR gene segments occurs through ___
random selection
recombination of TCR gene segments is mediated by _____ that brings two segments close together
lymphocyte-specific VDJ recombinase (RAG)
what is the 1st step of recombination of TCR gene segments
recombination of D & J segments
what is the 2nd step of recombination of TCR gene segments
recombination of V segments with fused D-J element
what is the 3rd step of recombination of TCR gene segments
recombination of C segments with fused V-D-J element
_____ diversity is limited
combinatiorial
____ diversity is unlimited
junctional
what are the ways that junctional diversity is generated
- exonucleases
- terminal deoxyribonucleotidyl transferase (TdT)
- tremendous diversity
Pre-T cells express one chain of antigen receptor called ___
pre-TCR