Antibody Structure and Function

Question 1

nowmal antibody responses are

Answer 1

polyclonal

Question 2

antibodies bind to

Answer 2

antigens, specifically at their corresponding epitope

Question 3

multiple myeloma

Answer 3

• plasma cell tumor
• creates a monoclonal antibody response
• derived from a single cell
• these are all the exact same antibodies
• hone to bone marrow and dirupt hematopoiesis
• lowered WBCs with increased susceptibility to infection
• decreases RBC leading to anemia
• see a drastic increase in serum gama globulin

Question 4

another word for antibody

Answer 4

immunoglobulin

Question 5

antibody structure

Answer 5

• consists of a light chain and a heavy chain
• the N terminus has 2 regions with both light and heavy chains and these are the variable regions
• C term conatins only one heavy chain region and this is constant
• variable regions known as Fab (antigen binding) and constant is known as Fc (crystalizable)
• heavy chains and light chains are held together via disulfide bonds

Question 6

CDR

Answer 6

• complimentarity determining region
• hypervariable region
• this is the regions that actually makes contact with the epitope on the antigen

Question 7

classes of antibodies

Answer 7

• these are antibodies with different constant regions
• mu, delta, gamma, alpha, and epsilon
• within these there are subclasses

Question 8

polymeric immunoglobulins

Answer 8

• formed by IgM and IgA
• IgM forms a pentamer, these are always made by IgM producing plasma cells
• IgA forms a dimeric antibody
• polymeric antibodies contain a J-chain protein

Question 9

attachment of antibody to a B cell

Answer 9

• one Ig-beta and one Ig-alpha are bound to the anitbody and these are what anchors the antobody to the B cell membrane
• Igb and Iga function in delivering signals to the B cell

Question 10

viral entry into cell

Answer 10

• virus binds to receptors on the cell surface
• receptor mediated endocytosis of the virus
• acidification of endosome triggers fusion of virus with cell and entrance of viral DNA
• Ab blocks binding to virus receptor

Question 11

viral and bacterial neutralization

Answer 11

-Ab binds to site on capsid/bacteria which would typically facilitate entry into a host cell

Question 12

opsinization via IgG and Fc-gama-R

Answer 12

• when immonoglobulin is bound to its target, it can be crosslinked with Fc receptors on macrophages and then endocytosed with its bound antigen
• if an immunoglobulin is not bound to its target antigen, then it can not be cross linked with Fc receptors on macrophages
• Fc-gama receptors mediate opsonization
• IgG is an important opsonin

Question 13

antibody dependent cellular toxicity

Answer 13

• antibody binds antigens which are bound to the surface of their target cell
• antibodies are recognized by NK cells via Fc receptors
• this cross linking signals the NK cell to kill the target cell
• target cells dies via apoptosis
• NK cells express Fc-gama-R
• NK cells also induce some virus infected or tumor cells to undergo apoptosis

Question 14

mast cell activation via IgE cross linking

Answer 14

• IgE antibodies are bound to Fc receptors on mast cells
• when these antibodies are multivalently cross linked with antigen, this causes release of granular contents
• this response function in immunity to worms
• it is also a key element in allergic reaction

Question 15

what Abs do antigen specific receptor binding

Answer 15

all of them

Question 16

neutraliation

Answer 16

IgA and IgG

Question 17

complement activation

Answer 17

IgM and IgG

Question 18

opsonization

Answer 18

IgG

Question 19

ADCC

Answer 19

IgG

Question 20

mast cel activation antibody

Answer 20

IgE

Question 21

what processes are Fc-R dependent

Answer 21

opsonization

• ADCC
• mast cell activation

Question 22

what antibody calss does the fetus have>

Answer 22

-IgG

Question 23

mouth lungs, stomach, and intestine Ab

Answer 23

-IgA

Question 24

breast milk Ab

Answer 24

IgA

Question 25

mothers body antibodies

Answer 25

IgG and IgA

Question 26

when the infant is born what does his immunoglobulin comp look like

Answer 26

- they have adult levels of IgG - the half life is 3-4 weeks - the infant will have protction via maternal Ab for a few months

Question 27

TDAP vaccine

Answer 27

- tetanus, diptheria, pertussis - recommended with each pregnancy to ensure protection for infants who are too young for vaccination but at high risk for severe illness

Question 28

secretory immunoglobulin

Answer 28

-the predominant Ig in milk and saliva is IgA (SIgA)

Question 29

secretion of IgA

Answer 29

- poly-Ig receptor on the basolateral surface of epithelial cells allows for receptor mediated endocytosis - this ednosome is trancytosed - release of IgA dimer at apical surface

Question 30

common mucosal immune system

Answer 30

-concept that describes the fact that immune responses that occur at one mucosal site can result in IgA secreting cells migrating, via the lymphatics and blood, to distant mucosal sites