Antibody and antigen Flashcards
What is a B-cell receptor
Membrane bound Ig on the B-cell surface
What is an antibody
Secreted Ig of the same antigen specificity as the BCR
What are antigens
foreign and endogenous substances recognized by the immune system
what is an immunogen
antigen that induces an immune response
What is immunoglobulin that is membrane bound
B-cell receptor
What is the function of immunoglobulin
Both BCR and secreted Ab bind Ag, Ag binding to the BCR signals B cell to: divide, differentiate, secrete Ab
What is the basic structure of antibody
Two identical heavy chains and two identical light chains
What are the divisions of Light chains of antibodies
Variable region (both on light and heavy), and constant region
What is a characteristic of variable region
varies between different B-cells (daughter B cells are identical)
What is a characteristic of a Constant region
Ab from same animal have similar constant region
What is a paratope
combined portion of light and heavy variable regions of antibody, 2 identical Ag binding sites per core Ab structure
What does the flexible portion on constant region of heavy chain do
allows better binding of antibody in diverse situations
What are the 5 major classes of antibody
IgM, IgG, IgD, IgE, IgA
Where are the differences in the isotypes of antibodies
in the constant region
Antibodies from the daughter cell have…..
different isotypes, but only one specificity
Characteristics of IgM
pentamer, 10 binding sites, high avidity, first Ab produced in immune response
Where is IgM found
serum and lymph
What is the first antibody produced
Igm