Antigen/Antibody Reactions

Question 0

5 classes of antibodies in mammals?

Answer 0

IgG, IgM, IgA, IgE, IgD

Question 1

Ag vs Ab?

Answer 1

antigen - Ag

antibody - Ab

Question 2

class of antibody determined by what?

Answer 2

the heavy chain constant region

Question 3

Fab

Answer 3

antibody portion that is variable region on heavy and light chain

Question 4

Fc

Answer 4

constant region of the heavy and light chain

Question 5

hypervariable regions

Answer 5

in the light and heavy variable regions of antibody

involved with the antigen binding that is complementary to epitope

Question 6

CDR

Answer 6

hypervariable regions also known as the complementarity determining region
-location of junctional diversity

6 CDRs per antibody and TCR
3 light chain and 3 heavy chain

each antibody has 2 binding sites

Question 7

CDR3

Answer 7

has the most variability

Question 8

idiotope

Answer 8

CDR hypervariable regions of the antibody

Question 9

isotype

Answer 9

class of the antibody

determined by the C region of the heavy chain

differ in size, charge, sequence, and carbohydrate content

9 isotypes in humans with functional differences
-all the basic Y structure

Question 10

allotype

Answer 10

allelic differences in the heavy chain

-we all have suttle differences in our genetics

Question 11

idiotype

Answer 11

antigenic differences in the V regions

- we all see an antigen differently
- this is our idiotypic antigen

Question 12

what isotype is not bifunctional?

Answer 12

IgD

Question 13

bifunctionality of antibody?

Answer 13

antibody binds antigen and mediates effector function

Question 14

IgM

Answer 14

5-10% of total serum

in a pentamer form held by disulfide bonds
has a J chain - in the mucosa; immunity

10 binding sites for antigens

first antibody produced in a primary response
also, first produced by neonates
bc first one in line of C regions on gene

can be membrane bound or secreted (mIgM - membrane bound)

Question 15

what antibody for primary response?

Answer 15

IgM

Question 16

IgG

Answer 16

80%

primary antibody of secondary immune response

four classes:
IgG1, 2, 3, 4
all four can cross placenta
IgG 1 and 3 - bind Fc on phagocytes
IgG 3 - activator of complement
IgG 2 - relative restricted to carbohydrate antigens
IgG 4 - intermediate affinity for phagocytes

Question 17

IgG four classes?

Answer 17

1, 2, 3, 4

all cross placenta

Question 18

IgG 1

Answer 18

high affinity to Fc receptors on phagocytes

Question 19

IgG 2

Answer 19

relatively restricted to carbohydrate antigens

Question 20

IgG 3

Answer 20

efficient activator of complement

Question 21

IgG 4

Answer 21

intermediate affinity for Fc receptors on phagocytes

Question 22

CD markers

Answer 22

Fc receptors for IgG

Question 23

CD 16

Answer 23

NK cells, monocytes, macrophages, and granulocytes

Fc receptor for IgG

Question 24

CD32

Answer 24

on B cells, monocytes/macrophages, and granulocytes

Fc receptor for IgG

Question 25

CD64

Answer 25

on monocytes/macrophages

Fc receptor for IgG

Question 26

IgA

Answer 26

constituent of the secondary immune response

10-15% total antibody
can be a polymer with J piece (promotes secretory peptide)

secretory - colostrum, saliva, tears, GU tract, digestive

concentrated along mucous membrane surfaces

Question 27

IgE

Answer 27

low concentration in serum

high affinity for basophils and mast cells

CD23a and CD23b

powerful pharmacologic reactions

- asthma, hay fever, peanut butters
- helminth infections

**important in worm defense

Question 28

IgD

Answer 28

less than 1% of serum

monomeric form on the membrane of B cells

no function in serum

have both IgM and IgD on membrane with same antigen specificity

Question 29

antigen

Answer 29

foreign molecule that binds to an antibody

**whether or not they induce an immune response

Question 30

immunogens

Answer 30

antigen that causes an immune response

Question 31

epitope

Answer 31

specific part of antigen that contacts the antibody binding site

epitope binds the idiotope

Question 32

pathogen

Answer 32

organism that causes disease

Question 33

hapten

Answer 33

small molecules that bind antibody but won’t cause immune response unless bound to carrier macromolecule

**used in vaccinations

**also leads to penicillin allergy

Question 34

endogenous antigens

Answer 34

body’s own cellular components or intracellular pathogens

classified as:

- autoantigens
- alloantigens
- intracellular pathogens

Question 35

autoantigen

Answer 35

type of endogenous antigens

self-antigen
-ex autoimmune disease

Question 36

alloantigens

Answer 36

type of endogenous antigen

tissue specific antigen
ex/ABO or HLA

Question 37

exogenous antigens

Answer 37

antigens enter body or freely circulate the body fluids and are trapped by APCs

classified as allergens, latrogenic, or microbial

**latrogenic - doctor induced

Question 38

factors influencing immunogenecity

Answer 38

molecular mass (smaller less likely to provoke immunity)
	**why happens need large molecule to bind to

foreignness (won’t respond to self)

chemical composition (more complex molecule more immunogenic)

physical form (particulate more immunogenic than soluble)

degradability (easily phagocytosed are more immunogenic)

genetic factors (differences in individual immune repertoire)

age (older has weaker immune response)

Question 39

why subQ administration better?

Answer 39

phagocyte activation further increases the immune response

Question 40

adjuvants

Answer 40

substances that can enhance the immune response

can have undesirable side effects such as fever and inflammation

Question 41

immunological priming

Answer 41

at slightly lower dose

atopic disease and hypersensitivity

Question 42

immunogen dose that is higher than optimal dose

Answer 42

annergy - cells cannot respond

method of peripheral tolerance

Question 43

vast majority of immunogens are?

Answer 43

proteins

Question 44

nucleic acids immunogenecity?

Answer 44

poor

although, they are good if single stranded

Question 45

epitopes recognized by B cells?

Answer 45

determined by the size of the antigen binding site of antibody

can bind soluble molecules

can bind proteins, polysaccharides, and lipids

Question 46

epitopes of T cells?

Answer 46

only see a sequence of amino acids in protein

does not see thing in 3D

8-15 AAs in a row

free peptides are not recognized
-need to be bound to HLA (MHC)

cannot bind soluble antigens

Question 47

T dependent antigens

Answer 47

require both T helper cells and B cells

**all T-dependent antigens are proteins

involved in class switching and affinity maturation

Question 48

T-independent antigens

Answer 48

non-protein

can stimulate antibody response without help

usually multiple identical epitopes that can cross-link BCR

Question 49

mitogens

Answer 49

cause cell to undergo division

LPS is an activator of B cells in humans

Question 50

superantigens

Answer 50

activate a large number of T cells

*look into this more

Question 51

antigen/antibody bonds?

Answer 51

non-covalent

hydrogen, electrostatic, van der waals, hydrophobic

all together gives a high affinity bond

Question 52

affinity

Answer 52

strength between antibody and its antigens

Question 53

avidity

Answer 53

strength of interaction between multivalent antigen and multivalent antibody

**avidity dependent on multiple affinities

Question 54

hapten-carrier effect

Answer 54

basis of many drug allergies

Question 55

monoclonal antibodies

Answer 55

mAB or moAb

immune cells are clones of a single parent cell

Question 56

first melanoma drug?

Answer 56

monoclonal antibody for CTLA-4

Yervoy = Ipilimumab

Question 57

ELISA

Answer 57

utilize monoclonal antibodies

ex/ pregnancy test

Question 58

flow cytometry

Answer 58

monoclonal antibodies

looking for fluorescently marked antibodies

Question 59

immunohistochemistry

Answer 59

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