Humoral Immunity (Waziry)

Question 1

IgM function,,?

Answer 1

BCR (w/ IgD) on naive B cells, secreted IgM mainly in the circulation, first antibody class produced in the adaptive response, activates complement, powerful agglutinin

Question 2

Which antibody is the most abundant in circulation, activates complement, enhances phagocytosis, ADCC, neutralizes pathogens, and crosses placenta?

Answer 2

IgG

Question 3

Which antibody has a secretory form that prevents colonization at mucosal surfaces?

Answer 3

IgA

Question 4

Which antibody is on BCR on naive B cells along w/ IgM ?

Answer 4

IgD

Question 5

Which antibody in the presence of antigens, triggers the release of inflammatory mediators from mast cells and basophils?

Answer 5

IgE

Question 6

what does neutralization do?

Answer 6

prevents pathogen-host binding

Question 7

Main neutralizing antibody in blood?

Answer 7

IgG

Question 8

What do opsonizing antibodies do?

Answer 8

they coat the target, identifying it for destruction or removal by other immune cells

Question 9

Opsonization depends on?

Answer 9

depends on the ability of the constant region to interact w/ Fc receptors on other cells

Question 10

what are Fc receptors found on?

Answer 10

macrophages, neutrophils, eosinophils, DCs, & NK cells

Question 11

Bound Fc receptors signal the cell to do what?

Answer 11

to kill and degrade the ingested particle via oxidative burst

Question 12

(T/F) antibodies are the only soluble factor that can opsonize pathogens

Answer 12

FALSE

Question 13

Opsonization can also be carried out by ___ and ____ which are produced by innate complement pathway & can help remove pathogens before adaptive response is available!

Answer 13

C3b and C4b

Question 14

Once the humoral response is activated, what will be produced in order to activate the classical cascade?

Answer 14

IgM

Question 15

What occurs when C1 binds to 2+ antigen-bound antibodies?

Answer 15

The complement cascade is triggered, forming the MAC

Question 16

ADCC can be mediated by:

Answer 16

IgG, IgA and IgE

Question 17

ADCC is mainly carried out by:

Answer 17

NK cells, neutrophils, macrophages, and eosinophils

Question 18

Eosinophils express high affinity Fc receptors for which antibodies in order to opsonize helminths?

Answer 18

IgE

Question 19

NK cells express low affinity Fc receptors for which antibodies in order to opsonize infected cells?

Answer 19

IgG

Question 20

__ response is when innate response cells fill in the gap while adapted response is mounted

Answer 20

Primary response

Question 21

___ response involves innate and adaptive working together right away!

Answer 21

secondary response

Question 22

Which antibody is predominant in primary response? what about secondary response?

Answer 22

IgM-primary

IgG- secondary

Question 23

What does the lag/latent phase entail?

Answer 23

initially, antigen is presented and lymphocytes are activated–> activated B and T lymphocytes undergo proliferation/differentiation

Question 24

(T/F) no detectable level of antibody in serum during lag phase

Answer 24

true

Question 25

What does the log phase entail? (this is what we measure)

Answer 25

plasma cells secreting antibodies, serum antibody levels increase

Question 26

What does the plateau phase entail?

Answer 26

antibody titer is at its peak

Question 27

What does the decline phase entail?

Answer 27

plasma cells begin to die and antibody titer begins to decline as less antibody is made

Question 28

T-dependent responses can be categorized as either ___ or ____

Answer 28

primary or secondary

Question 29

No T-cell involvement, no CD40-40L interaction, dominated by IgM, no memory B cell development, and lower antibody titers all describe what type of response?

Answer 29

T-independent responses