Flashcards in Ppt 6 Generation of Humoral Effector Mechanisms Deck (61):
3 functions of antibodies
3) activate classical complement
when you have a thymus independent antigen stimulating B cells reaction, you will generally not make these 3 things:
1) no memory
2) no isotype switching
3) no somatic mutation
thymus dependent antigen are what kind of molecules?
thymus independent antigen are what kind of molecules?
is there isotype switching in thymus dependent antigen?
is there memory in thymus dependent antigen reaction?
when B cells interact with T helper cells, what 3 things are needed for the interaction to take place?
MHC 2 and co-stimulation, CD40-CD40L
THelper 2 cells will cause B cells to have memory?
once the costimulation (B7), MHC 2 and CD40-CD40L interaction occurs between T Helper cell and B cell, what happens?
B cell expresses receptor for cytokines
When complement activates, what complement product attaches to microbes? what receptor on B cells recognizes this?
C3d recognized by B cell CR 2 receptor
in X-linked Hyper IgM, what antibodies are deficient?
IgA, IgE and IgG
in X-linked Hyper IgM, what receptor is deficient?
T helper cells generally stimulate B cells to have 3 things:
1) affinity maturation
2) isotype switching
what is a Hapten?
antigenic molecule that can't induce immune response by itself
what does a hapten need to be attached to?
a large protein
what happens when you inject Ig into another animal?
it causes an antibody response
what is isotype?
means that you have different types of constant regions in different heavy chains that can be switched
what is allotype?
multiple alleles (variations in polypeptides) that code for the same isotype
what is idiotype?
a specific shape in the variable region that determines that antigen recognition
what antibody heavy chains have 4 domains and 1 hinge region?
IgG, IgA, IgD
what antibodies have 5 domains and no hinge?
what chain holds the different IgA dimers (trimers)?
what antibodies can form multimers?
IgM and IgA
this antibody is used for ADCC?
this antibody is produced after IgM
this antibody is actively transported through the placenta?
this antibody has no known function and is found on surface of B cells?
this antibody is bound to mast cells and basophils?
this antibody mediates the Type 1 Hypersensitivity?
this antibody protects against parasites?
This antibody is mainly found in secretions like tears, saliva, intestinal and respiratory tract?
this antibody is found in submucosa?
this antibody prevents binding of bacteria and viruses to the mucosa?
this antibody is found in breast milk?
this is the antibody first produced in primary response?
this antibody has a plasma valence of 10:
this antibody has a low affinity:
this antibody has the highest avidity of all
what does IgA use to gain passage into the mucosa?
the secretory component
what is trancytosis?
transport across the cell from the basement M to luminal surface
what Fc receptor is used to bind IgE to mast cells?
how will antibodies protect adjacent cells from infection?
they bind to active sites of microbes before they bind to other cells
what F c receptor is used for IgG and is involved in ADCC by NK cells?
what antibodies does FcyRI bind?
binds IgG 1 and IgG 3
what is FcyRI used for?
this Fc receptor is used for feedback inhibition of B cells
what IgG subtypes are used in ADCC?
IgG 1 and IgG3
ADCC can also be used by what other cell recognizing IgE?
when an antibody has monomer valency, how will its avidity be?
when an antibody has bivalent valency, how will its avidity be?
when a antibody has polyvalent valency, how will its avidity be?
what is the valency of an antibody?
how many places it has to bind antigen
what is the affinity of an antibody?
how strong it will bind to antigen with only 1 of its receptors
what is the avidity of an antibody?
how strong it will bind to antigen using all of its receptors
how many alleles does a B cell express for an antibody heavy chain and light chain?
1 allele only
how does an antibody achieve diversity (3 ways)?
1) by having different combinations of heavy chains with light chains
2) by somatic hypermutation
3) combinatorial and junctional diversity
what starts the process of somatic hypermutation?
what does AID do in a B cells?
class switching and somatic hypermutation
do you have a high Kd or low Kd when antibodies have high affinity for antigen?
you need interaction of this receptor on B cells and t helper cells to have class switching from IgM