Unit One Immunoglobulins Flashcards
Antibodies are secreted by
Effector B cells or plasma cells
Antibodies can do what
Clear the blood and tissues of invading pathogens and their toxins
Antibodies general or specific
Specific
A B cell produces only one specificity of what throughout its life
Antibody
Antibody binding to a specific pathogen results in what
B cell proliferation and differentiation
What is antibody clonal selection
Large amounts of antibodies are produced specifically for a single pathogen
What agammaglobulinemia
No ability to produce antibodies
Where is the variable part of the antibody
On the ends of the Y structure
Differences in types of antibodies are where on the antibody
Constant region which shows different functions
Antibodies are made up of how many polypeptide chains
4
Antibody has how many heavy chains
2 identical
How smaller chains does antibody have
Two identical
The variable region on AB forms the
Antigen binding site
The constant region has no
Variation in amino acid sequence
Where is the hinge region
In the middle and provides flexibility
what is Fab in antibody
Fragment antigen binding region that binds to antigen
Fc region in antibody does what
Mediates the effector functions
Difference in Fc regions indicate difference in what
Isotopes
What are the different types of antibodies
IgG, IgM, IgD, IgA and IgE
What are the hypervariable regions in antibodies
Unstructured protein regions in antigen binding site, contains different amino acid structures
What are the complementarity determining regions in antibody (CDR1-3)
Binds to the antigens complementarily
Aka of antigenic determinant
Epitope
What is an epitope
Part of antigen that binds to antibody
What is a multivalent antigen
Antigen that contains more than one epitope or copy of the epitope
What are the two types of epitope
Linear and discontinuous
What are linear epitope
Successive amino acids
What are discontinuous epitopes
Amino acids brought together because of folding
What is hybridoma production
Making immortal B cells through B cells fusion with a tumor cell
Each antibody requires what gene segments
VDJ genes (variable, diversity and joining)
What is somatic recombination
Recombination of VDJ segments
What is junctional diversity
Heptamer cleaved from D and J segment to form hairpin, Hairpin open to expose nucleotides, add nucleotides and find match, and then add more nucleotides to create more diversity
Naive B cells express what antibodies
IgM and IgD
Alternative mRNA splicing allows for
Expression of IgM and IgD on cell surface
After antibodies are recombined, the bound immunoglobulin express what on their cell surface
IgM and IgD
What assistant proteins are on the cell surface of bound immunoglobulins
Igalpha and Igbeta that help with intracellular signaling
When a B cell recognizes its antigen the membrane bound IgM and IgD become
Secreted antibodies
After B cell activation, what further increases antibody diversification
Somatic hypermutations
Somatic hypermutations occur through
Point mutations
Aka of somatic hypermutations
Affinity maturation
What is affinity maturation
Mature affinity of antibody every time matches with antigen
Somatic hypermutation/ affinity maturation changes what on antibody
Variable region
What is isotype switching
Change in constant region causing different function of antibody
What antibodies have subclasses
IgG and IgA
Function of antibodies
Neutralization, opsonization, and activation of complement
Neutralization with antibodies
Binding to pathogen or toxin and preventing it from interacting with human cells
What antibodies work with neutralization
IgM, IgG and IgA
Opsonization with antibodies
Coating the protein with opsonins to allow phagocytosis to take place more easily
What antibodies work with opsonization
IgG and IgA
Activation of compliment with antibodies
Antibodies bound to the surface of a bacteria can activate complement for lysis of the bacterium
What antibodies are part of activation of complement
IgM, IgG and IgA
IgM function
Complement activation, opsonization in blood
Function of IgA
Mucosal surface, in gut and bodily fluids
IgE function
Recruits mast cells, eosinophils and basophils to fight parasites, helps with allergies
Function of IgD
Located in the upper respiratory tract ot interact with commensal and pathogenic respiratory bacteria
IgG function
Most abundant with great flexibility. Best antibody