Flashcards in T cell differentiation, subsets, receptors Deck (74)
T and B cell lymphocytes begin to express antigen receptors ...
as precursor cells in the primary lymphoid tissue following random recombination of genes
if mature t cell expresses 10 million TCR molecules on its plasma membrane, how many antigen specificities would the cell express?
where are gamma-delta T cells found?
found as intraepithelial lymphocytes
What cytokines do Th1 cell produce?
what cytokines do Th2 cells produce?
IL4, IL5, IL13
what cytokines do Th17 cells produce?
Where do Naive T cells encounter antigen?
In the paracortex of lymph nodes or the PALS of the spleen
when APCs and T cell travel to the lymph nodes this optimizes the interaction of antigen presentation
What happens upon Naive CD4 T cell activation?
after antigen presentation, there is clonal expansion and differentiation to either Th1, Th2 or Th17 cells
What type of infection do Th1 cells aid in?
and aid in inflammtion
what type of infection doe Th2 cells aid in?
Parasitic - Helmiths
what type of infections do Th17 cells aid in?
Some bacteria and fungi
bring in additional neutrophils
what is the main leukocyte that Th1 cells recruit?
what is the main leukocyte recruited by Th2 cells?
what is the main leukocyte recruited by Th17 cells?
what kind of antibody isotypes are stimulated by Th1 cells?
Fc receptor binding IgG subclasses
What types of antibody isotypes does Th2 stimulate?
Naive CD4 T cells interact with antigen
presented on MHC II molecules by APCs in the secondary lymphoid tissue
List the steps of T cell activation
Differentiation - during differentiation get effector and memory
Effector CD4 T cells
activate macrophages and B cells
Effector CD8 T cell
Kill infected target cells
where are T cells activated?
paracortex of lymph nodes
or PALS of spleen
what molecules are required for T cell activation?
APC - MHC2, CD80/86 (B7)
T cell - CD3, CD4, CD28, TCR
what are the three signals required for T cell activation? CD4 or CD8
signal 1 - interaction with MHC - adhesion molecules stabilize interaction.
signal 2 - co stimulation
signal 3 - cytokines from APC
In cell to cell interactions of activation of Cd4 cells, what molecules play a role in adhesion?
LFA-1 on CD4 T cells
ICAM-1 on the APC
What is absolutely required activation?
CTLA4 interacts with
when is IL 2 produced?
after antigen presentation but before proliferation
promotes T cell proliferation
positive feedback to the cell producing it
Naive CD4 T cell secretes IFN-y and IL-12 to induce
Naive CD4 T cells release IL-4 to induce