CH.4 B Flashcards
what gives rise to undifferentiated lymphocytes
red bone barrow
what cells do B and T cells come from
undifferentiated lymphocytes
what is the stroma made up of in the thymus
epithelial cells and connective tissue
where do T cells develop in the thymus
stroma
what % of lymphs in the peripheral blood are T cells
60 to 80
what is the T lymphocyte precursor
thymocytes
where do early thymocytes enter the thymus
corticomedullary junction
Once thymocytes enter the corticomedullary junction where do they go
outer cortex
what cytokine is critical for growth and differentiation of T cells
interleukin 7
what drives the T cell differentiation process
chemokine
how do thymocytes develop into t cells
rearrangement of genes
what is a double positive (DP) T cell
expresses CD 8+ and CD 4+
what is a double negative (DN) T cell
does not express either CD 8+ and CD 4+
T or F: the majority of intrathymic cells die before maturing
T
there is orderly _____ rearrangement of genes coding for the T cell receptor
random
what is specific about T cell maturation
distinct surface markers appear during diff stages
T or F: early thymocytes have CD4 and CD8 markers
F
what DNA chain on the TCR is rearranged 1st
beta
are the majority of T cells DP or DN
DP
what T cell receptor chains recognize Ag
alpha and beta
what part of the antigen do alpha and beta recognize on Ag
variable regions
how do TCR (T cell receptors) recognize different Ag
the alpha and beta chains get rearranged
what chromosome is the TCR beta chain
7
what region on the beta chain is rearranged 1st
C region