Ag Receptors: Lymphocytes

Question 1

Ag

Answer 1

molecule that is recognized by the immune system. loosely associated with adaptive response

Question 2

immunogen

Answer 2

an Ag that evokes a specific immune response

Question 3

tolerogen

Answer 3

an Ag that induces immunologic tolerance

Question 4

Endogenous

Answer 4

body’s own cellular components or intracellular pathogens

Question 5

auto-Ag

Answer 5

self-Ag

Question 6

allo-Ag

Answer 6

tissue specific Ag

Question 7

Exogenous Ag

Answer 7

Ag enter the body or system and freely circulate in the body fluids and are trapped by the APCs

Question 8

haptens

Answer 8

small molecules which cannot induce an immune response alone
induce a response when coupled with a carrier protein

Question 9

BCR components

Answer 9

Surface Ig

IgBeta and IgAlpha (signaling - contain ITAMs)

Question 10

Ab do two things

Answer 10

promote killing/removal of Ag-Ab complex

integral in B cell differentiation

Question 11

digestion pdt of papain and pepsin

Answer 11

papain - cuts above the hinge == 2x Fab, Fc

pepsin - cuts below the hinge == 1F(ab’)2, fragments

Question 12

within each variable domain of an Ab exists three

Answer 12

hypervariable domains on the most distal portion of the Ab from the constant region
most important region for binding Ag

Question 13

the isotype of an Ab is determined by

Answer 13

the heavy chain (c domain)

Question 14

allotype

Answer 14

subtle allelic differences exist within H chains - important for transplantation

Question 15

idiotype

Answer 15

Ag determinants of variable region idiotypes may differ in how they interact with an Ag, but will both recognize it (and therefore have effector function)

Question 16

J chains are present on

Answer 16

IgA and IgM

JAM

Question 17

Ab class produced by neonates

Answer 17

IgM

Question 18

first Ab class produced in primary response

Answer 18

IgM

Question 19

Ab isotype that contains 10 binding sites

Answer 19

IgM

Question 20

Ab type expressed on the surface of mature activated B cells

Answer 20

IgM or IgD

Question 21

predominant Ab isotype of secondary immune response

Answer 21

IgG

Question 22

most abundant IgG subclass

Answer 22

IgG1

Question 23

Ig classes that activate classical complement

Answer 23

IgM
IgG
(may be more but these for sure)

Question 24

predominate Ig class of mucosal immunity

Answer 24

IgA

Question 25

J chain of IgA and IgM are recognized by what protein for secretion across an epithelial barrier

Answer 25

Poly-Ig receptor | endocytosed with the IgA molecule and secreted with it

Question 26

Ab isotype involved in defense against hilminth

Answer 26

IgE

Question 27

Ab isotype which Fc region binds CD23

Answer 27

IgE

Question 28

affinity vs avidity

Answer 28

affinity is the strength of a single interaction | avidity is the additive strength of multiple Ag-Ab interactions

Question 29

Epitopes that can be recognized by B lymphocytes/Abs

Answer 29

1) conformational determinant (3d structure) 2) linear determinant (either accessible only when denatured or in both native/denatured forms 3) determinant made available by proteolytic cleavage

Question 30

t dependent Ags are

Answer 30

always proteins

Question 31

t independent Ags can be

Answer 31

polysaccharides, lipids (usually multiple identical epitopes that can cross link BCRs)

Question 32

most variable region within TCR

Answer 32

CDR3 (v region contains 3 hypervariable regions, of which 3 is the most variable)

Question 33

gamma/delta T lymphocytes are primarily located in the

Answer 33

epithelial/mucosal compartments not MHC/HLA restricted can recognize lipid Ags and DAMPs

Question 34

TCR receptor complex constituents

Answer 34

``` alpha/beta heterodimer with variable (and hypervariable) regions 2x CD3 (for a total of four ITAMS) 2x delta chains (for a total of six ITAMs) ```

Question 35

TCRs recognize protein in what conformation

Answer 35

primary sequence, only when presented | free peptides are not recognized by TCRs

Question 36

superAg binding and MoA

Answer 36

``` bind the Vbeta region of TCR and MHC class II molecules hyper-activate immune system to release bio-active cytokines from T cells == cytokine storm with a bunch of nasty effects ```

Question 37

superAg manifest in

Answer 37

staph enterotoxins (food poisoning) staph toxic shock toxin (TSS) staph exfoliating toxins (scalded skin syndrome) strepto pyrogenic exotoxins (shock)

Question 38

mAb are produced by

Answer 38

isolated mouse spleen cells that produce Ab of interest fusing with immortal myeloma line culture in selected media (that filters out myelomas/spleen cells that didnt fuse) isolate clones success