Immune cells

Question 1

development of TH1 cells is triggered by what transcription factors

Answer 1

STAT4 and T-bet

Question 2

development of TH2 cells is triggered by what transcription factors

Answer 2

STAT6 and GATA

Question 3

what triggers differentiation of TH1 cells

Answer 3

IL-12

Question 4

what triggers differentiation of TH2 cells

Answer 4

IL-4

Question 5

what do TH1 cells release

Answer 5

INF-γ, IL-2 and TNF-β

Question 6

what do TH2 cells release

Answer 6

IL-4, IL-5, IL-6, IL-10 and IL-13

Question 7

what are the main effector cells of TH1 cells and what do they activate

Answer 7

Macrophages, cytotoxic T cells, B cells - mainly cell mediated immunity

Question 8

what are the main effector cells of TH2 cells and what do they activate

Answer 8

B cells - activating humoral immunity

Question 9

what does overactivation of TH1 cells cause

Answer 9

hypersensitivity and autoimmunity

Question 10

what does overactivation of TH2 cells cause

Answer 10

allergy and hypersensitivity

Question 11

what are the two receptors of IgE antibodies

Answer 11

1 Fc epsilon receptor 1 (High affinity)

2 Fc epsilon receptor 2 (aka CD23) (Low affinity)

Question 12

where is the FcεRI found and what does binding of antigens to IgE-FcεRI lead to

Answer 12

expression is inducible in eosinophils by IL-5, is constitutively expressed in mast cells and basophils

Binding of antigens to IgE already bound by the FcεRI cells causes cross-linking of the bound IgE and the aggregation of the FcεRI,
Inducing signaling cascade -> leading to the degranulation

Question 13

what does FcεRII do

Answer 13

Regulates IgE levels by competing and breaking the cycle at B cell and Eosinophil (stops degranulation)
(only when IgE levels high)

Question 14

eosinophils make up ___ of WBCs

Answer 14

1%

Question 15

basophils make up ___ of WBCs

Answer 15

0.1%

Question 16

what are eosinophils

Answer 16

white blood cells that contain small granules that release chemical mediators

Question 17

(eosinophilia)high levels of eosinophils in your blood and tissues usually indicates

Answer 17

a parasitic infection, an allergic reaction or cancer.

Question 18

eosinophils cause IgE/FcεRI mediated release of what two things

Answer 18

– eosinophil peroxidase (cytotoxic)

– major basic protein (cytotoxic and induces mast cell and basophil degranulation)

Question 19

how long do eosinophils persist in circulation for and how long can they remain in the tissues

Answer 19

 Eosinophils persist in the circulation for 8–12 hours, and can survive in tissue for 8–12 days in the absence of stimulation.

Question 20

what are basophils

Answer 20

a types of white blood cell that release granules to fight fungal or bacterial infections and viruses.

Question 21

what do basophils release

Answer 21

– pre-formed mediators (from the granules): serine proteases, histamine, serotonin, heparin
– newly formed lipid mediators: prostaglandin D2, leukotriene C4, platelet-activating factor
– newly formed cytokines: eosinophil chemotactic factor, Interleukin 4

Question 22

what is the critical cytokine in the development and production of IgE

Answer 22

IL-4

Question 23

what does heparin do

Answer 23

anti-coagulation - decreases clotting ability in blood