Exam 2: Chapter 4 Flashcards
What are some properties of IgG?
Transport across placenta, diffusion into extravascular sites
What receptor is IgM missing that makes it unrecognizable to macrophages/neutrophils?
Fc receptor
What fragments are formed when papain cleaves an antibody?
Two fragment antigen binding (Fab) fragments and a fragment crystallizable (Fc) fragment
What does the antigen binding region interact with?
The epitopes on the surface of pathogens
What two joints form during combinational diversity?
A signal joint (lost over time) and a coding joint (codes for protein)
What regions surround the Hypervariable regions?
Frame work regions
What is somatic hypermutation?
Process by which activated B cells will try to increase V domain diversity by mutating the V coding sequences
How is the expression of IgM and IgD regulated?
Alternative splicing
What is a naïve B cell?
A B cell that has rearranged both heavy chains and both light chains
What is the function of the RAG 1 and RAG 2 complex?
To cut the DNA
Where does antibody flexibility come from?
The hinge region
What is a unique property of IgG4?
In circulation, two IgG4 molecules can exchange pieces to form functionally monovalent antibodies that recognize two things
What are the three hypervariable regions called?
Complementarity Determining Regions (CDR) 1, 2, and 3
What are recombination signal sequences?
Conserved recognition sequences that are 7 and 9 bp long, separated by either a 12 or 23 bp spacer
What does the 12/23 rule ensure?
That VJ always join in light chains, and that VDJ always join in heavy chains
What is affinity?
The binding strength of an antibody
What is flow cytometry?
A method that is used to analyze cell populations or sort cells by Fluorescence Activated Cell sorting (FACs)
How are the three hypervariable regions encoded?
Two are encoded by sequence differences in the V segment, and the third is generated by the junction of VJ and VDJ in the light and heavy chains
What two forms of IgA are produced?
Monomers and dimers
How are antibodies produced?
By B lymphocytes that secret them into the plasma of blood and lymph
What is a main function of IgA?
Neutralization
Which antibody is the most abundant in the blood and lymph?
IgG
What is the first antibody made by B cells?
IgM
What type of molecule has the ability to digest antibodies?
Proteases