Module 2 Flashcards
Anti- BODY
What are the 4 functions of antibodies?
Neutralization, opsonization, complement activation, and antibody-dependent cell-mediated cytotozicity (ADCC)
What are the isotypes of immunoglobulins?
IgM, IgG, IgA, IgE, IgD
What are the 2 types of Light chains?
Kappa and lambda
What are the 2 regions on lt chains
constant and variable
Which part of an antibody determines the class/isotype?
Heavy chains
Heavy chain on IgG
gamma chain
Heavy chain on IgM
mu chain
A unique AA sequence that is common to all immunoglobulin molecules of a given class in a given species
isotype
minor variations of isotype sequences that are present in some individuals but not others
allotypes
How does antibody cleavage by papain differ from pepsin
Papain takes off the top and splits the disulfide bond, while pepsin does not cleave the disulfide bond
Which part of an antibody determines the function?
the Fc (fraction crystallized) region
Which part of an antibody determines the specificity?
the Fab (fragment antigen binding) region
What is useful for treating overdoses (like digoxin) and as antivenom?
Fab fragments
fraction of serum separated by electrophoresis that is enriched with antibody
gammaglobulin
Bence Jones proteins are also known as what?
Light chains
Which two kinds of antibodies can be found as monomers?
IgG and IgE
Which two kinds of antibodies can be found in multimers with J chain?
IgM and IgA
What is the main kind of immunoglobulin found in serum?
IgG
Which antibody can fix complement, opsonize, bind to cells for ADCC, neutralize toxins and viruses, and participate in agglutination and precipitation rxns?
IgG
How dcan macrophages, monocytes, and neutrophils be so efficient in phagocytosis?
They have IgG Fc receptors
Which immunoglobulin diffuses into extravascular spaces best?
IgG
What is IgM also known as?
Macroglobulin
Where is IgM mostly found?
Intravascular pool
Which immunoglobulin best triggers the classical complement pathway?
IgM
Which immunoglobulin is best for agglutination reactions?
IgM
Which immunoglobulin is made in plasma cells and found mostly in MALT?
secretory IgA
What has 5 Ig-like domains derived from epithelial cells and is a specific receptor for IgA
sIgA
What neutralizes toxins from microorganisms, prevents bacterial adherence to mucosal surfaces, and is found in breast milk?
secretory IgA
Aggregation of IgA immune complexes may trigger what?
alternate complement pathway
What can get trapped in mucus and has to be eliminated by respiratory ciliary movement?
IgA and antigens
Which immunoglobulin is found on the surface of immunocompetent but unstimulated B cells?
IgD
Which antibody attaches to basophils, eosinophils, and mast cells through high-affinity Fc epsilon RI receptors
IgE
Hay fever, asthma, vomiting, diarrhea, hives, anaphylaxis are all part of which type of allergic reaction?
Type I immediate hypersensitivity
What antibody is involved with parasitic infections?
IgE
Do plasma cells have surface receptors?
no, they have them as b cells but once they cleave off, they become plasma cells
Which antibody may play a role in b cell development and maturation?
IgD
Which antibody is transported across mucosal epithelium?
IgA
Antibody monomer with transmembrane anchor
B cell receptor
Which two parts of b cell receptors transmit signals?
IgBeta and IgAlpha
Antibodies can recognize which types of epitopes?
conformation, discontinuous, and linear
T cells can recognize which type of epitopes?
linear epitopes only (think AA chains)
Binding strength between an antibody and a single antigenic determinant. Measure of binding strength on one arm of the antibody
Affinity
number of antibody-combinding sites and the number of epitopes in a single antigen. Measure of total binding strength
avidity
What determines the specificity of antibodies?
the hypervariable regions
What is derived form single plasma cells fused with myeloma cells?
monoclonal antibodies
plasma cells fused with myeloma cells
hybridoma
Indefinite source of antibody with single specificity, used for diagnostics and treatment of disease
monoclonal antibodies
What are the germ-line loci that code for antibodies?
Variable (V) region, Joining (J) region, Constant (c ) region, and diversity (D) region
V and J gene segments code for what?
light chain variable region
V, D, and J gene segments code for what?
heavy chain variable regions
Which gene is associated with heavy chains?
Diversity (D)
What events determine antigen specificity?
- Selection of VDJ gene segments and VJ gene segments, 2. junctional diversity making P- and N- nucleotides, 3. Selection variable region gene segments of heavy and lt chains, 4. Somatic hypermutation (this step is antigen dependent)
RAG (recombination activating genes) genes are involved in what?
VDJ and VJ segment recombination for antibodies (also T cell receptor formation)
Mature B cells express what receptors with the same specificity?
IgM and IgD
How can B cells express both IgM and IgD receptors
differential RNA processing encoding the same VDJ of the H-chain
Isotype switching involves what?
Recombination of the VDJ region with another constant region gene segment
Where does somatic hypermutation occur?
germinal centers of lymphoid tissues in response to antigens and activated T helper cells
RAG (recombination activating genes) genes are involved in what?
Recombination signal sequences (RSS)
N-nucleotides are non-templet nucleotides added by what?
Terminal deoxynucleotide transferase (TdT)
N- and P- nucleotides are part of what step of determining antigen specificity?
junctional diversity
If a patient has a mutation that inactivates all RAG genes, what happens?
Both B and T cells are absent
Which step of antigen specificity contributes to affinity maturation?
Somatic mutation
What step of antigen specificity explans the development of IgM followed by IgG response to the same antigen?
Isotype switching
