T Helper and Gamma Delta T cells, Th cell and B cell interaction

Question 1

What are the different types of lymphocytes?

Answer 1

B cells, gamma delta t cells, CD4 T-helper cells, CD8 cytotoxic T-cells, and CDTfh cells

Question 2

How do B cells recognize antigen?

Answer 2

on intact, unprocessed molecules

Question 3

How do gamma delta t cells recognize antigen?

Answer 3

on intact, unprocessed cell surface molecules

Question 4

How do CD4 T helper cells recognize antigens?

Answer 4

exogenous peptides, processed and presented on MHC II molecules

Question 5

How do CD4 T regulator cells recognize antigens?

Answer 5

self peptides on MHC II

Question 6

How do CD8 cytotoxic cells recognize antigen?

Answer 6

endogenous peptides processed and presented on MHC I

Question 7

What is the signature cytokine of TH1?

Answer 7

interferon gamma

Question 8

What are the functions of TH1?

Answer 8

secrete cytokines to activate macrophages, neutrophils, NK cells, and CTL cells to be better killers and signal B cells to make opsonizing and complement fixing antibodies (IgG)

Question 9

What are the signature cytokines of TH2?

Answer 9

IL3, IL4, and IL5

Question 10

What are the functions of TH2?

Answer 10

activate mast cells and eosinophils and activate B cells to make IgE

Question 11

What are the signature cytokines of TH17?

Answer 11

IL17 A

Question 12

What is the function of TH17?

Answer 12

attract and activate neutrophils and monocytes

Question 13

What are the signature cytokines of T regulatory cells?

Answer 13

TGF beta

Question 14

What is the function of T regulatory cells?

Answer 14

suppress T cell response

Question 15

What are the signature cytokines of Tf?

Answer 15

IL21

Question 16

What is an example of an extracellular pathogen?

Answer 16

Staphylococcus or tetanus toxin

Question 17

How is the antigen processed, to what T cell is it presented to, what s the effector response, and what is the outcome of the alpha beta T cell response to an extracellular pathogen?

Answer 17

processed on MHC II, presented to a T helper cell, effector response is by TH1 and TH17, and the outcome is the production of IgG and attraction of neutrophils

Question 18

What is an example of an intravesicular pathogen?

Answer 18

mycobacteria bovis

Question 19

How is the antigen processed, to what T cell is it presented to, what s the effector response, and what is the outcome of the alpha beta T cell response to an intravesiuclar pathogen?

Answer 19

processed on MHC II, presented to a T helper cell, effector response is by TH1, and the outcome is interferon gamma’s activation of macrophages to become more potent killers

Question 20

What is an example of a helminthic pathogen?

Answer 20

roundworms

Question 21

How is the antigen processed, to what T cell is it presented to, what s the effector response, and what is the outcome of the alpha beta T cell response to an helminthic parasite?

Answer 21

processed on MHC II, presented to a T helper cell, effector response is by TH2, and the outcome is the production of IgE leading to mast cell degeneration and the binding of eosinophils

Question 22

What is an example of a cytosilic pathogen?

Answer 22

a virus

Question 23

How is the antigen processed, to what T cell is it presented to, what s the effector response, and what is the outcome of the alpha beta T cell response to an cytosolic pathogen?

Answer 23

processed on MHC I and II, presented to a T helper cell and cytotoxic T cell, effector response is by CTL and TH1, and the outcome is the killing of the cell via apoptosis and ADCC

Question 24

Where are gamma delta T cells located?

Answer 24

on mucosal surfaces

Question 25

What type of immunity are gamma delta T cells involved with?

Answer 25

they seem to be in between innate and adaptive immunity

Question 26

What is the function of gamma delta T cells?

Answer 26

they can secrete cytokines or cytotoxic T cells

Question 27

How can an immune response to one type of pathogen inhibit the response to another type of pathogen (use example of TH1 response currently going on)?

Answer 27

If there is a TH1 response going on, IFN will inhibit TH2

Question 28

How can an immune response to one type of pathogen inhibit the response to another type of pathogen (use example of TH2 response currently going on)?

Answer 28

if there is a TH2 response going on, IL4 will inhibit TH1 from responding

Question 29

What can you do to get T cell help to B cells when B cells are responding to a polysaccharide antigen?

Answer 29

if you covalently bind the polysaccharide to a protein, the B cell will then ingest the antigen, process and present it on the Th cell which will result in activation, the b cells will proliferate and differentiate into plasma cells to produce antibodies and opsonize polysaccharide antigen on the surface of the bacterium

Question 30

What are the major signals required to get T helper cell activation?

Answer 30

TCR + CD4 needs to bind to MHC II and peptide, co-stimulatory molecules, and cytokines

Question 31

What determines the subtype of T helper cell that will predominate in the response?

Answer 31

the co-stimulatory molecules and cytokines tell the T helper cell what to predominate

Question 32

What pathway do killed vaccines follow?

Answer 32

the exogenous pathway

Question 33

Briefly explain how the exogenous pathway works.

Answer 33

the vaccine is phagocytized, broken up into peptides in a vesicle, bound to a MHC II molecule, and then presented to a CD4 cell

Question 34

What pathway do live vaccines follow?

Answer 34

They can follow both exogenous and endogenous (primarily endogenous)

Question 35

Briefly explain how the endogenous pathway works.

Answer 35

The foreign molecule is tagged with ubiquitin, processed by a proteosome, moved to the MHC I pathway and presented to the CD8 cell