Immunology 5

Question 1

2 other ways CTLs can kill (other than perforin/granzyme)

Answer 1

secreting lymphotoxin TNF-b = will kill cells with the right receptor. express Fas Ligand = trigger apoptosis in cells with Fas receptor.

Question 2

CTLs are very ___ in their killing

Answer 2

specific

Question 3

NK cells are _____, derived from?

Answer 3

large granular lymphocytes. derived from precursors in bone marrow

Question 4

NK cells: what immune system

Answer 4

innate, they act before specific immune responses are generated

Question 5

NK cells are activated by what 4 things

Answer 5

IFN gamma, IL2 and IL 12

Question 6

when activated, NK cells do what

Answer 6

secrete cytokines associated with cytotoxicity like IFN gamma and TNF

Question 7

2 mechanisms of recognition by NK cells

Answer 7

recognizing self protein in tumour/infected ells. recognizing and killing cells that don’t express enough MHC Class I.

Question 8

how to NK cells kill

Answer 8

similar to CTL: perforin + granzyme to induce apoptosis, or will secrete cytokines to induce apoptosis

Question 9

NK cells can also kill by ____?

Answer 9

ADCC = antibody dependent cell mediate cytotoxicity. They express Fc receptors, can acquire specificity for antigen by binding Ab

Question 10

cytokines: def?

Answer 10

short and long range molecules that transmit signals for differentiation and proliferation

Question 11

cytokines: act on how many cell types? how many effects?

Answer 11

most cytokines act on more than one cell type. one cytokine mediates multiple effects even on a single cell type

Question 12

cytokines: one cell type can respond? cytokines show? cytokines interacting with cytokines?

Answer 12

one cell type can respond similarly to more than one cytokine. show synergy or antagonism. induce, enhance or inhibit synthesis of other cytokines.

Question 13

two major classes of CD4 helper T cells. they make different?

Answer 13

TH1 and TH2 - make different subsets of cytokines. TH1: IL2, IFNy and lymphotoxin. TH2: IL4, 5, 10, 13

Question 14

most important TH1 cytokine

Answer 14

IFN gamma

Question 15

4 general categories of cytokines

Answer 15

mediators of natural immunity (trigger inflammatory response). mediators of lymphocyte activation, growth, differentiation. mediators of immune-mediated inflammation. mediators of immature leukocyte growth/differentiation

Question 16

endotoxic shock: what? aka?

Answer 16

critically low BP associated with gram negative infection. aka septic shock

Question 17

endotoxic shock: happens when?

Answer 17

when products from the cell walls of certain gram negative organisms leak into circulation and cause massive direct activation of macrophages

Question 18

exotoxin shock: aka? what?

Answer 18

toxic shock: like endotoxin shock, but stimulation of massive number of T cells via super antigens made by bacteria getting into the blood

Question 19

superantigens: bind what?

Answer 19

binds strongly to MHC Class II, will bind to all TCRs rwith a particular VB sequence regardless of antigenic specificity