CD4 T cells

Question 1

TH1 cells 1) secrete what 2) Bind to what? 3) outcome 4) What signal is delivered by APC to activate this cell 5) What else can TH1 cells provide help to?

Answer 1

1) secretes IFNy/ IL12 2) Macrophages 3) Dead intracellular bacteria 4) IL12 and IFNy 5) B cells for antibody production

Question 2

TH2 cells 1) secrete what 2) Bind to what? 3) outcome 4) What signal is delivered by APC to activate this cell 5) What can this cell provide help for the most?

Answer 2

1) Scretes IL4, IL5 and IL13 2) Doesnt bind to anything but the secreted chemicals effects other cells 3) Eosinophils, mast cell and plasma cell antibodies are effected 4) IL4 5) Switching to IgE, parasites

Question 3

TH17 cells 1) secrete what 2) Bind to what? 3) outcome 4) What signal is delivered by APC to activate this cell 5) Can promote what?

Answer 3

1) Screte IL17, IL6 2) Fibriplasts, epithelial calls which secreted chemokines 3) Neutrophils response enhanced. 4) TGFB and IL6 5) Barrier integrity from fungi?

Question 4

TFH cells 1) secrete what 2) Bind to what? 3) outcome 4) What signal is delivered by APC to activate this cell

Answer 4

1) Doesnt secrete shit but maybe IL21, ICOS? 2) B cell with IgM 3) Secreted effector B cell with antibodies. Isotype switching, affinity maturation 4) IL6

Question 5

Treg cells 1) secrete what 2) Bind to what? 3) outcome 4) What signal is delivered by APC to activate this cell

Answer 5

1) Acts as an inhibitor so it doesnt allow maturation of DC and in turn leads to lack of T cell activation.Can maye TGBF and IL10 4) TGFB

Question 6

CD8 T cells - CTL 1) Main function? 2) Pathogens targeted

Answer 6

1) kill virus infected cells 2) viruses

Question 7

T helper cells are ONLY activated how?

Answer 7

when signals are received from the innate immune system so when PAMPs interact with PRR to provie costimulation

Question 8

How do superantigens work?

Answer 8

They can bind directly to conserved regions of class II chains together with particular group of VB chains of many T cell receptor. Large amounts of IL1, IL2 and TNF are released and these result in significant pathology

Question 9

Activated B cells can also act as what?

Answer 9

As APC because the antigen that has bound to the BCR has been internalised via endocytosis and now these antigens that have been degraded into peptides can be displayed on the B cell. This B cell then helps T cells which in turn can help other B cells to undergo isotype switching

Question 10

Activated, antigen specific CD4 cells migrate to the infected site and activate what?

Answer 10

Activate tissue macrophages and causes release of a range of cytokines

Question 11

overall process

Answer 11

Question 12

Virus specific CD8 cells migrate to the infected site and so these cytotoxic T cells trigger what and how?

Answer 12

Trigger death by creating holes in the target cell membrane (perforin) and induced apoptosis via granzymes.

FasL on the CD8 cell binds to Fas on the infected epithelial cells

Question 13

describe the summary

Question 14

How does the innate IS activate the adaptive IS?

Answer 14

Upregulats co stimulator molecules on APC by binding through PRR

Cytokine production biases lymphocyte differentiation

Complement products activate B cells

Question 15

How does the adaptive Immune system activate the innate imune system

Answer 15

Produces antibodies to act as osponins, thus increasing phagocytosis, triggering C cascade.

Producing cytokines, eg IFNgamma and cell surface molecules. CD40L to boost innate system function

Question 16

describe the summary of infection

Answer 16