Antibodies Flashcards
Which antibody has the longest half-life, plays a major role in controlling infections and crosses the placenta?
IgG = present in high numbers at 2nd exposure to an antigen; 4 sub-classes
Which antibody is missing in some people and is present as a secretory piece made on epithelial cell.
IgA = expressed in mucosal tissues and forms dimers
What antibodies activate the complement system?
IgG and IgM
What antibody is present in high numbers during RBC hemolysis from an unfavorable transfusion reaction?
IgM = the first Ig upon antigen invasion; increases transiently; responsible for agglutination
What antibody plays a crucial role in the allergic process?
IgE = stimulates mast cells to degranulate and plays a role in parasite control. This is an adaptive system mediator in Type 1 hypersensitivity.
During the primary exposure to a pathogen, ____ levels are high; whereas, during the secondary exposure ___ levels are higher.
IgM’s are high; IgG’s are high which leads to high affinity of immune cells for the antigen.
Each B-cell produces only one kind of AB to react with only one _____ on one type of antigen.
Epitope
Describe what occurs during Somatic Hypermutation.
A high level of mutations occurs within the variable region of ABs. This can result in cancer.
Which immunoglobulin is predominant in secretions?
IgA
Which immunoglobulin is produced by the fetus in response to in utero infection?
IgM = also present as natural antibodies to ABO antigens.
Which antibody can both opsonize bacteria and activate complement?
IgG
Pathogen-specific antibodies of this class indicate a recent infection.
IgM = present at the primary exposure to a pathogen
After a complete immunization series, antibodies to tetanus toxin are mostly of this class.
IgG = highest opsonization and neutralization activities.
Each molecules contains 4 identical anti-gen binding sites.
IgA = forms dimers with 4 identical binding sites.
Describe the purpose of Junctional Diversity in relation to antibodies.
The junctions of DNA that will be put together after splicing are points in which mutation can occur, thus adding to the variety of possible antibodies produced.
