antibody strx and fxn

Question 1

immunoglobulins

Answer 1

same as antibody; they are membrane bound and soluble receptors

Question 2

epitope is? made of?

Answer 2

antigenic determinant; part of an antigen that is the binding site for an antibody; usually a carb or peptide

Question 3

vaccine antigen

Answer 3

can be a single molecule, or can be a more complex particle

Question 4

examples of a vaccine antigen

Answer 4

DTaP and HPV vaccine. can be a viral capsid that is empty on the inside

Question 5

antibody can recognize

Answer 5

linear, folded, or denatured antigen/epitope proteins.

Question 6

hapten

Answer 6

small molecules that can don’t induce an immune response ONLY when BOUND to a carrier molecule

Question 7

example of a hapten

Answer 7

penicillin which disrupts the cell wall of bacteria which can make the cell wall bind to a RBC or something else; the immune system says NO and can get rid of it.

Question 8

how many chains in an Ab/immunoglobulin?

Answer 8

2 light, 5 heavy

Question 9

most common immunoglobulin?

Answer 9

IgG

Question 10

Where is the N terminus/Cterminus in an Immunoglobulin

Answer 10

both of the N terminuses are at the tip of the Y; the C is at the base

Question 11

special features of an immunoglobulin?

Answer 11

disulfide bond between two heavy chains in the hinge region

Question 12

where is the antigen-binding site?

Answer 12

in the variable region

Question 13

what does papain do?

Answer 13

it cleaves the disulfide bond and you get the separation of the Y into three parts: two identicle FAB molecules and one crystallizable base

Question 14

pepsin does?

Answer 14

cleaves below the hinge region; there is no functionality of this molecule, but the Fab half can still bind to an antigen

Question 15

what does the hinge region do?

Answer 15

it allows the two arms of the Ab molecule to have some flexibility; this way the Ab can bind to epitopes with different steric configurations

Question 16

down side of hinge region?

Answer 16

this is where the Ab is more linear and therefore it is more subject to proteolysis

Question 17

More specific Ab configuration

Answer 17

the heavy chain has three constant domains and one variable domain

Question 18

structure of Fab?

Answer 18

made of Beta sheets that are linked together with a disulfide bond (think sandwich with a toothpick in it)

Question 19

why is the folding of Ab important

Answer 19

by folding in the pleat the parts of the protein that are more variable are exposed to make a unique Ab to create antibodies with different specificities

Question 20

what does the constant domain do?

Answer 20

determines the function and the class of the Ig. (remember that the constant domain is the heavy chain base)

Question 21

each constant domain can combine with?

Answer 21

a lambda or kappa light chain

Question 22

hinge regions are present in

Answer 22

igG, igD, igA; M and E have an extra heavy chain section on them.

Question 23

allotypic differences defn.

Answer 23

differences between two IgG molecules; eg. like one from mom and one from dad

Question 24

idiotypic differences defn.

Answer 24

differences between individual Ab molecules that will recognize different epitopes; their variable domain is different so they can recognize different stuff

Question 25

Binding strength is determined by?

Answer 25

the fit. better fit means a stronger binding. its non-covalent bonding

Question 26

affinity=

Answer 26

strength of interaction between the epitope and ONE antigen-binding site; there can be more than one binding site

Question 27

avidity=

Answer 27

the SUM of the strength of binding between an epitope and antigen binding site

Question 28

crossreactivity

Answer 28

sometimes two different Ab can share a same epitope;

Question 29

monoclonal antibodies

Answer 29

immortalized plasma cells usually mouse derived; you take B cells with a specific antigen and fuse them with tumor cells that are “immortal”; select for the cells that produce the antibody that you are interested in

Question 30

polyclonal antibodies

Answer 30

purified from serum of immunized animals (usually goats or rabbits) eg. ebola serum from recovered patients and give it to those with ebola

Question 31

chimeric Ab

Answer 31

part human, part mouse; -ximab

Question 32

humanized Ab

Answer 32

95% human, 5% mouse; -zumab

Question 33

human Ab

Answer 33

100% human; -umab; best for treatments; this type is less likely to develop anti-antibody response

Question 34

immunoassays. rank their specificity

Answer 34

radioimmunoassays and Elisa are most sensitive.

RIA, ELISA > agglutination > precipitation

Question 35

what is precipitation immunoassay

Answer 35

when the antibody and antigen complex; ideally, you want an equal amount of Ab to Ag. that gives you the most amount of precipitation.

Question 36

blood type

Answer 36

the antibodies for this are IgM. they don’t cross the placental barrier

Question 37

coombs test

Answer 37

uses anti-human immunoglobulin to cross link the RBCs

Question 38

rhesus factor

Answer 38

IgG antibodies that CAN cross the placental barrier

Question 39

ELISA test for HIV

Answer 39

can use to test for HIV; coat the wells with antigen and ad the serum sample. use chemistry to see if the person developed antibodies for HIV

Question 40

western blot for HIV

Answer 40

used as a secondary test for someone who had a positive HIV elisa test; test for proteins that are made by HIV

Question 41

immunofluroescence

Answer 41

take a biopsy and rinse it with a fluorescent Ab for that virus. if it lights up, its positive

Question 42

flow cytometry

Answer 42

take blood and mix with a fluroescent Ab for a cell type; you can run it through fluoroscopy and you can tell how many of cell type X you have present in a blood sample.

Question 43

flow cytometry and HIV/AIDS

Answer 43

great way to track the progression of AIDS; count how many CD4+ cells are present in the patient infected with HIV

Question 44

three loci that code for ___?

Answer 44

genes for the lambda(light chain), kappa(light chain); and heavy chain

Question 45

diversity gene segements are only in

Answer 45

heavy chain

Question 46

how do you regulate the chain genes?

Answer 46

recombination signal sequences that consist of spacers;

Question 47

how specifically is the spacer important in gene selection

Answer 47

a 23 gene spacer can ONLY recombine with a 12 gene spacer; therefore a 23 spacer cannNOT combine with a 23 spacer

Question 48

V(D)J recombinase

Answer 48

these enzymes are used to splice out parts of the Ab gene; RAG is one of the enzymes what works in the V(D)J group

Question 49

TdT does?

Answer 49

enzyme that adds nucleotides to joining regions of the D and J gene when it links back together.

Question 50

mutation in TdT

Answer 50

can cause a frameshift mutation of the coding sequence between the D and J regions

Question 51

what are the factors that work together to create overall Ab diversity

Answer 51

the different chains (kappa, lambda, heavy), imprecise joining, and nucleotide addition (with TDT enzyme)

Question 52

how could a naive mature B cell express more than one Ig type?

Answer 52

it is from alternative splicing; it just splices out different constant domains so it can co-express IgM and IgD. this is NOT isotype switching

Question 53

what do Ig alpha and Ig beta do?

Answer 53

when a B cell binds to an antigen, it does a conformation change and the Ig pair sends an intracellular signal to create a kinase cascade

Question 54

what doe b cells do after activation

Answer 54

they secrete antibodies, they do isotype switching, and somatic mutation(additional diversity)

Question 55

coombs tests

Answer 55

for IgG; uses hemagluttination