T Cells

Question 1

What part of immunity do T cells participate in?

Answer 1

adaptive, cell mediated immunity

Question 2

How kind of infections do T cells fight against?

Answer 2

mostly intracellular but also some extracellular

Question 3

How do T cells assist in defense against extracellular infections?

Answer 3

recruiting leukocytes that destroy pathogens and by helping B cells make effective antibodies

Question 4

Helper T cell effector function

Answer 4

Activation of macrophages

inflammation

activation and proliferation of T and B lymphocytes

Question 5

Cytotoxic T lymphocyte effector function

Answer 5

killing of infected cell

Question 6

Can T cells interact with free floating antigens?

Answer 6

no

Question 7

Activation of naive T cells requires what?

Answer 7

recognition of peptide-MHC complexes presented on dendritic cells

Question 8

What molecules are required to activate T cells?

Answer 8

MHC-complex on dendritic cells and costimulators

Question 9

CD4 T cells are mediated how?

Answer 9

by cytokines

Question 10

Naive CD4 T cells are activated by antigens: now what?

Answer 10

they secrete Interleukin-2, a growth factor that stimulates the proliferation of (clonal expansion) of the antigen specific T cells

Question 11

activated CD4 T clones can do one of two things, what are they?

Answer 11

1. Some will secrete cytokines and recruit leukocytes and stimulate production of microbicidal substance in phagocytes

others secrete cytokines that help B cells produce a type of antibody called immunoglobulin E (IgE) + activate eosinophils