Thrush - Immuno Antigens

Question 1

what is an antigen

Answer 1

any molecule that can interact with the products of the immune response; interaction bet. a receptor and a ligand, strength of binding is important in activation.

Question 2

what are 3 major categories of antigens

Answer 2

1. autoantigen: a self antigen
2. alloantigen: an antigenic diff within a species
3. xenoantigen: an antigenic difference beween species

Question 3

T/F The more foreign the antigen the greater the likelihood to activate the immune system.

Answer 3

true

Question 4

what is immunogenic

Answer 4

the ability to induce an Ab and or a cell mediated immunity response on its own.

Question 5

what are the most potent immunogens?

Answer 5

1. Proteins
2. polysaccharides
   - lipids and nucleic acids are usually not immunogenic

Question 6

what makes an antigen

Answer 6

1. foreigness
2. molecular size (larger the better)
3. chemical composition (the more complex, the better)
4. susceptibility to Ag processing/presentation (D not degraded…unlike the L form)

Question 7

what are haptens

Answer 7

small molecules that are antigenic but not immunogenic; often need to be attached to carrier to become immunogenic

Question 8

what is an epitope

Answer 8

actual part where IS recognized antibody molcule or T cell receptor; for a given protein Ag, there can be multiple T and B cell epitopes

Question 9

what are immunodominant epitopes

Answer 9

Are usually those that stimulate early and often the best response. Mutation causing loss of ID epitopes can weaken the immune response

Question 10

what is the importance in HIV/aids

Answer 10

loss of T cells that recognize ID epitopes

Question 11

____ are what make it bind to particular epitope

Answer 11

Receptor

Question 12

B cells are ____ epitopes. They can be sequential or non sequential

Answer 12

external

Question 13

T cells can have epitopes anywhere in protein, including ______. They are sequential. Ag must interact with ___ and ____

Answer 13

internally. TCR; MHC

Question 14

when are polysaccharides immunogenic

Answer 14

1. when attached to proteins or lipids
2. when associated with cells
3. highly complex carbs can be immunogenic

Question 15

what are mitogens

Answer 15

polyclonal activators of T and or B cells; They are not Ag specific; classic ex is LPS

Question 16

what are types of immunogenic molecules

Answer 16

1. mitogens
2. T independent antigens
3. T dependent antigens

Question 17

what are ch’s of TI Ags

Answer 17

1. response doesnt require T cells.
2. B cell response; no memory cells
   classic ex is polysaccharides

Question 18

what are ch’s of TD Ags

Answer 18

response requires T cell help (cytokines); generates immunological memory

Question 19

what is tolerance

Answer 19

suppression of the IS; relatively high and low doses are usually not immunogenic

Question 20

HIgh dose may be _____. Low dose may not be worth the ____

Answer 20

self; effort

Question 21

IV and ____ routes are generally less effective than ____ routes in part to how long the antigen stays in the body. ____ antigens can tolerize (stimulate anergy)

Answer 21

SC; IM; Oral

Question 22

____ are compounds that when mixed with immunogens, makes them more immunogenic. An adjuvant cannot make a ___ immunogenic (have to have the carrier present). They are NOT chemically bound to _____

Answer 22

adjuvants; hapten; immunogen

Question 23

Why use an adjuvant

Answer 23

increases half life of immunogen to stay in body longer, which stimulates immne reaction against microbes

Question 24

what are mechanisms of action of adjuvants

Answer 24

1. increase half life of immunogens
2. inc production of inflammatory cytokines
3. improved presentation and costimulation of APCs to T cells.

Question 25

The best immunogens are associated with ____in order to have proper T:B cell collaboration. The IS is extremely _____

Answer 25

proteins; specific