Maturation, Differentiation And Activation Of T-cells And TCR

Question 1

Types of lymphocytes

Answer 1

NK
B cells (humoral immunity)
T cells (cell-mediated immunity)

Question 2

In adaptive immunity, what are the molecules responsible for specific recognition of antigens?

Answer 2

Ig and TCR/BCR

Question 3

Positive selection for a T cell only occurs when

Answer 3

They have affinity for MHC

Question 4

Which cytokine promotes survival in T-cell maturation?

Answer 4

IL-7

IL-7 in thymus causes double negative T-cells

double + —> CD8 mature naive T-cell —> clonal expansion —> effector t-cell

Question 5

Activated B cells express what as costimulation?

Answer 5

B7 molecules

Question 6

Which cytokine stimulate naive T cells?

Answer 6

IL-2

Question 7

What triggers t-cell activation?

Answer 7

Antigen recognition w/ MHC complex

T cell activation is initiated by the binding of the T cell receptor (TCR) on the T cell surface to a specific antigen presented by a major histocompatibility complex (MHC) molecule on an antigen-presenting cell (APC),

Question 8

Significance of MHC ass. Antigen presentation

Answer 8

-ensures that t-cells see and respond only to cell-ass. Antigens
-separates b/w class 1 and class 2 allows the immune system to respond to whether it’s extracellular or intracellular (this is important b/c w/o MHC t-cells cannot distinguish b/w intra or extra microbes)