Ab Structure & Genetics Flashcards
Antibody producing cells
Plasma cells (type of B-cells)
COVID B and T cells seem to produce _____
immunologic memory
Antibody (Ab) can also be called
Immunoglobulin (Ig)
Part of antibody that binds antigen
Fab
Hypervariable region is called
complimentary determining region (CDR)
Classes of Immunoglobulins (Isotypes)
IgG IgA IgM IgE IgD
GAMED
What makes each class of Ig isotope different
Different Fc (constant) region
There are ___ different versions of IgG
four
There are __ different versions of IgA
two
We have a total of ___ Ig Isotypes
nine
A particular antibody will have ____ of the nine possible heavy-chain constant regions.
A particular antibody will have one of the nine possible heavy-chain constant regions.
The light chains associated with an antibody will be either ______ light chains or ______ light chains
The light chains associated with an antibody will be either kappa (k) light chains or lambda (l) light chains.
_____ is always secreted as a pentamer
IgM is always secreted as a pentamer
IgA producing plasma cells make either _____ ____ (antibody) or _____ ____ (antibody)
IgA producing plasma cells make either monomeric IgA or dimeric IgA
Polymeric Abs have a single _____ protein bound to the
Polymeric Abs have a single J-chain protein bound to the
All B cells have an antigen-specific receptor consisting of a ________ (two H-chains and two L- chains) plus a heterodimer of ______ and ______.
All B cells have an antigen-specific receptor consisting of a monomeric Ig molecule (two H-chains and two L- chains) plus a heterodimer of Ig-alpha and Ig-beta.
In B cell membrane ____ and ____ functions to deliver signals to the cell (signal transduction)
In B cell membrane Ig-alpha and Ig-beta functions to deliver signals to the cell (signal transduction)
B cells that have never been activated by antigen
Naïve B cells
B-cell receptor in Naive B cells has both ____ and ____
B-cell receptor in Naive B cells are IgM and IgD
B-cell receptor in memory B-cell are ___ or ___ or ___
B-cell receptor in memory B-cell are IgG or IgA or IgE
Antibody Effector Function
How an antibody helps eliminate a particular pathogen
Agglutination
Clumps antigens which makes them more readily removed by phagocytes
Neutralization of virus or toxin by Ab
When an antibody prevents a virus or toxin from entering a cell
Antibodies from COVID vaccine seem to produce ____ (effect) antibodies
Neutralizing
Inhibition of Bacterial adhesion
When antibodies prevent Bacteria from binding
Opsonization
Ability of antibodies to facilitate and enhance process of phagocytosis
Best antibody for agglutination
IgM
Activation of macrophage (opsonization) occurs via cross-linking of ____ (opsonin) and ____ (receptor)
Opsonization occurs via IgG and FcgR (receptor)
Phagocytosis of tumor cell
Antibody-dependent cellular phagocytosis (ADCP)
Antibody-dependent cellular phagocytosis (ADCP) implies phagocyte recognition of _____ specific for tumor antigens
Antibody-dependent cellular phagocytosis (ADCP) implies phagocyte recognition of IgG specific for tumor the antigens
Nature killer (NK) cells express ____ receptors for_____
Nature killer (NK) cells express Fc-receptors for IgG (FcgR)
NK cells destroy some virus-infected or tumor cells by _____.
NK cells destroy some virus-infected or tumor cells by inducing apoptosis.
Mast cell is highly specific for antibody _____
Mast cell is highly specific for antibody IgE
Why is IgE-Fc cross-linking in Mast cells different?
IgE binds to mast cell before binding to antigen
How does mast cell granule release get activated?
If at least 2 antibodies in mast cell come into contact with antigen, mast cell will release granule
Resting mast cell contains granules containing ____ and other ____
Resting mast cell contains granules containing histamine and other inflammatory mediators
The inflammatory response resulting from mast cell degranulation functions in _________.
The inflammatory response resulting from mast cell degranulation functions in immunity to worms.
Mast cell degranulation is also a key element in ______
Mast cell degranulation is also a key element in allergic reactions
Antibody functions (8)
- Ag-specific receptor
- Agglutination
- Neutralization
- Complement activation
- Opsonization
- Antibody-dependent cellular phagocytosis (ADCP)
- Antibody-dependent cellular cytotoxicity (ADCC)
- Mast cell activation
Antibody-dependent cellular cytotoxicity (ADCC)
Leads NK cells to recognize a target cell and induce apoptosis
Fc receptor antigenic antibody functions (4)
- Opsonization
- Antibody-dependent cellular phagocytosis (ADCP)
- Antibody-dependent cellular cytotoxicity (ADCC)
- Mast cell activation
Antibodies contained in all tissues of the body
- Monomeric IgA
2. IgG
Found primarily in Heart and Bloodstream
- Monomeric IgA
- IgG
- IgM
Found in high concentration in mucosal secretions (saliva, tears, etc.)
Dimeric IgA
Found beneath epithelial and cell mucosal surfaces (where mast cells live)
IgE
Ab transported to baby while in the placenta
IgG
Ab transmitted to baby through lactation
IgA
At birth an infant has adult levels of _____ (antibody)
IgG
The half life of IgG is about ____
4 weeks
The infant will have protection via maternal Abs for _____
a few months
Receptor that recognizes a dimeric IgA and transports it across epithelial cells and releases it to the lumen
poly-Ig receptor
Secretory IgA
IgA that has a remnant from poly-Ig receptor
IgA and Poly-Ig receptor bond is a ____ bond that must be cut by a/an ____
IgA and Poly-Ig receptor bond is a covalent bond that must be cut by a/an enzyme
Common mucosal immune system
Concept that immune responses that occur at one mucosal site result in IgA secreting cells migrating, via the lymphatics and blood, to distant mucosal sites.
Fragment variable (FV)
Variable and contains VH and VL. Also includes a binding site for antigen
You can link VH and VL via a polypeptide linkage in a lab and form a _____
You can link WH and VL via a polypeptide linkage in a lab and form a single chain FV (scFV)
Immunotoxin
You can put a toxin on scFV, so when it recognizes a tumor antigen it kills the cancer cell