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MCD- Immunology > Extras > Flashcards

Flashcards in Extras Deck (27):
1

What are the acute phase proteins and what do they do.

C reactive and serum amyloid bind to bacteria cell wall
Man an binding lectins bind to mannose

2

How do antibodies kill viruses?

Opsonisation
Prevent antigen from binding to receptor
Activating complement
Killed by NK

3

Describe the action of opsonins

Antibody binds to antigen
Complement glycoproteins binds to pathogen
Activate neutrophils = phagocytosis

4

What mechanisms do neutrophils use to kill pathogens?

Oxygen dependent and independent

5

What are the roles of complements?

Opsonisation
Lysis
Clearing antigen-antibody complex
Inflammation

6

What are the 2 types of mast cells?

Mucosal and connective

7

What is an immunoglobulin domain?

Internal intrachain disulphide bonds

8

What part of the variable region of the antibody binds to antigen?

Complementary determining verging at end of variable region

9

What are isotypes and allotypes?

Isotypes = different constant regions
Allotypes = different variable regions

10

What enzymes is involved in the removal of unused segments of DNA?

V(D)J Recombinase

11

What gene codes for VDJ Recombinase and what disease is caused by a deficiency of this gene?

Rag gene
SCID

12

Describe T cell independent pathway

Log polysaccharide with repeating subunits bind to BCR
PAMPs also provide co-stimulation

13

Describe the T dependent pathway

Dendritic and B cell present the same antigen to helper T
Helper T activated = clonal expansion
Activates B

14

What improves the immune response for B cells between primary and secondary ?

Somatic hypermutation
Antigen maturation

15

Describe the structure of MCH Class I

3 alpha chains and 1 beta microglobulin chain
Alpha chains are bigger and transmembrane

16

Describe the structure of MCH Class II

2 alpha and 2 beta chains
All the same size and all transmembrane

17

Describe antigen presentation by MHC class 1

Virus protein enters and fuses with proteosome
enters ER by TAP
MHC class 1 assembles
Chaperone protein aids folding of MHC

18

MHC class II presentation

Antigen move to endocytic pathways
MHC class II enters ER
Associates with invariant chain
Invariant chain digested leaving clip protein
Replace clip protein with antigen

19

2 ways of inducing apoptosis

Granzyme and perforin
Fas ligand binds to Fas receptor

Both release caspases

20

What are the 2 phases in delayed type hypersensitivity

Sensitisation = initial exposure
Effector = delayed response

21

5 types of helper T

T helper 1=inflammation
T helper 2=activation of B
T helper 17=control bacteria
Follicular T helper= generate isotypes
T reg = regulatory

22

Hypercytokinemia and sepsis?

Too much immune response
Hypercytokinemia = too many cytokines
Sepsis = bacteria in blood

23

What is immunological tolerance ?

Specific unresponsiveness to antigens

24

2 types of tolerance.

Central = destroy self reactive T and B before enter circulation
Peripheral = destroy self reactive T and B that don’t reach circulation

25

What does AIRE do?

Allow thymus expression of all genes

26

Describe 4 mechanisms of peripheral tolerance

Anergy = ACP shuts down helper T
Deletion =apoptosis of helper T
Ignorance = no ACPs in some areas
Regulation = t reg regulate helper T

27

What transcription factor do t reg express?

FoxP3