Immunology G

Question 1

What cells are part of the innate immune response?

Answer 1

Complement proteins
NK
Mast cells
Neutrophils
Macrophages

Question 2

Functions of neutrophils

Answer 2

Release TNF alpha to activate dendritic cells to show co-stim molecules
Phagocytose pathogens
Degranulate to kill
Nets

Question 3

What are the three types of helper t cells (CD4)

Answer 3

TH1
THfh
TH2

Question 4

What is a b cell receptor composed of?

Answer 4

Membrane bound antibodies of type IgM or IgD

Question 5

Describe transendothelial migration

What binding molecule does the endothelium have vs the neutrophil

Answer 5

Endothelium= icam and selectin
Neutrophil= integrin

Question 6

What are some of the features of a neutrophil

Answer 6

Granulocyted and a multilobar nucleus

Question 7

What type of MHC class identifies self cells? What T cell binds to these?

Answer 7

MHC class I and CD8 cytotoxic cells.

Makes sense as want to be able to kill immediately without having to stimulate other things like CD4 cells

Question 8

During neutrophil transendothelial migration what receptors are present on the epithelium and on the neutrophil?

Answer 8

Integrin present on the NP which binds strongly to I-cam on the endothelium and weakly to selectin

Question 9

What are the methods of cell death by neutrophils?

Answer 9

Phagocytosis; then degradation by ROS or anti-microbial proteins

Degranulation; exocytosis of granules that kill without selectivity

NETs; release of DNA from neutrophil by cell lysis to trap pathogens for phagocytes

Question 10

What are the functions of the complement response

Answer 10

Create a membrane attack complex; causing cell lysis

Pathogen opsonisation by C3b

Question 11

Describe a B cell receptor

Describe a T cell receptor

Answer 11

Membrane bound antibody of IgG or IgD (GAMDE)

Membrane bound heterodimer of alpha and beta chain

Question 12

How is antigen receptor diversity generated?

Answer 12

By the transcribing genes being segmented where the heavy chain is transcribed by genes V, D and J and the light chain is transcribed by V and J

Question 13

How is a T cell activated?

Answer 13

By the binding of an MHC class protein and a co-stimulatory molecule from a dendritic cell.

Question 14

How does a B cell become activated?

Answer 14

By the binding of a pathogen plus helper t cell binding

Question 15

What are the different fates of an acitvated B cell?

Answer 15

Differentiate to a short lived plasma cell that secretes low affinity antibodies

Differentiate to a germinal centre (follicle) to produce both long lived plasma cells secreting high affinity antibodies and memory cells.

Question 16

What is the structure of IgM?

Answer 16

It is a pentamer

Question 17

What is the function of Th1 lympocytes

Answer 17

Bind with IFN alpha to macrophages to hyperactivate them

Question 18

What is the function of THfh lympocytes

Answer 18

Binds with B cells to activate them, giving them the first signal to become activated to germinal centre(follicle)

Question 19

What is the function of Th2 lympocytes

Answer 19

Secrete IL-5 that attracts eosiophils and IL-13/ IL-4 that act on a B cells germinal centre to stimulate production of IgE