Chp 5—T-cells Flashcards
chain type in T cell receptor
2 light chains, alpha and beta
___ always present on T cell receptor
MC
____ complexes are associated with T cell receptor on either side:
CD3
𝜺δ dimer
𝛄𝜺 dimer
T cell receptor signal transduction conducted by…
where?
𝜁-dimer
sits beneath receptor in cell
2 t cell receptor isotypes and prevalence
𝛼:β receptor - most common
𝛄:δ receptor - occurs more in tissues, function varies by animal
binding regions of T cell receptor
CDR1
CDR2
CDR3
T cells only bind antigen when…
it’s presented on an MHC
produces majority of diversity in T cell receptor
junctional diversity - 1000x more than in B cells
more diversity in T cell or B cell receptors?
T cell
2 cellular immune systems & what they do (briefly)
vesicular system —extracellular pathogens —MHCII —CD4 T cell activation
cytosolic system —intracellular pathogens —MHCI —CD8 T cell activation
cells that vesicular system occurs in
B cells & phagocytes
_____ T cells bind with MHCII
CD4
type 1 vs type 2 CD4 cells
type 1: binds macrophages, triggering cellular immune response
type 2: bind B cells, triggering humoral immune response
licensed cells
MHCI is present with self-peptides
NK passes it by
____ T cells bind with MHCI
CD8
CD8 triggers…
apoptosis
polypeptides composing MHCI
β2-microglobulin
𝛼1, 𝛼2, 𝛼3
antigen bound between ___ and ___ on MHCI
𝛼1 and 𝛼2
MHCI peptide length
8 AA
CD8 protein contacts ____ to stabilize bond
𝛼3
polypeptides composing MHCII
β1, β2, 𝛼1, 𝛼2
antigen bound between ___ and ___ on MHCII
𝛼1 and β1
MHCII peptide length
25 AA
CD4 proteins contact ___ & stabilize bond
β2