Nature of Antibodies Flashcards
Electrophoresis is at pH ___, immunoglobulins appear
primarily in the _____________
Electrophoresis is at pH 8.6, immunoglobulins appear
primarily in the gamma band
Combine with antigens on cellular surfaces and thereby cause the destruction of these cells either
1. _____________ (outside the
blood vessels within the mononuclear- phagocyte system, also known as _______________________) or
- ______________ (within blood vessels through the action of
________________)
Combine with antigens on cellular surfaces and thereby cause the destruction of these cells either
1. extravascular (outside the
blood vessels within the mononuclear- phagocyte system, also known as Reticular endothelial system (RES))) or
- intravascularly (within blood vessels through the action of
complement)
is the primarily organ where the antigens are destroyed
Spleen
THEORIES OF ANTIBODY DIVERSITY
- EHRLICH’S SIDE-CHAIN THEORY (SPECIFIC RECEPTOR)
- TEMPLATE THEORY (GENERAL RECEPTOR)
- CLONAL SELECTION
_____________ postulated that certain cells had specific surface receptors for antigen
Paul Ehrlich postulated that certain cells had specific surface receptors for antigen
Theory?
Occurred once antigen was introduced, it would select the cell with proper receptor, combination would take place and receptors would break off and enter the circulation as antibody molecules
EHRLICH’S SIDE-CHAIN THEORY (SPECIFIC RECEPTOR)
Who proposed the TEMPLATE THEORY (GENERAL RECEPTOR)?
Felix Haurowitz
Theory?
Antibody producing cells are capable of synthesizing a generalized type of antibody and when contact with an antigen occurs, the antigen serves as a mold or template and alters protein synthesis so hat antibody with specific fits is made
TEMPLATE THEORY (GENERAL RECEPTOR)
Most accepted theory for antibody diversity
CLONAL SELECTION
____________ and ________________ independently supported the idea of clonal selection process for antibody formation
Niels Jerne and Mcfarlane Burnet independently supported the idea of clonal selection process for antibody formation
Theory?
The key premise is that individual lymphocytes are genetically programmed to produce one type of immunoglobulin and that a specific antigen finds or selects those particular cells capable of responding to it, causing to proliferate
CLONAL SELECTION
BASIC STRUCTURE OF AN ANTIBODY
* Consist of 4 polypeptide chains
* Subdivided into _______________ and _______________
BASIC STRUCTURE OF AN ANTIBODY
* Consist of _polypeptide chains
* Subdivided into 2 Heavy chain (large chain) and 2 Light chain
(L chain)
________________ and ________________ worked on Immunoglobulin G (IgG)
Gerald Edelman and Rodney Porter worked on Immunoglobulin G (IgG)
A flexible Y-shaped molecule with four protein chains
MONOMER
What are the 2 identical light chains in monomer?
2 identical light chains- Kappa or Lambda chain
How many identical heavy chains in monomer?
2
two sections at the end of Y’s arm. Contains also the antigen binding sites (Fab) or the paratope. The Fab is identical on the same antibody, but vary from one antibody to another
VARIABLE REGION
T or F
The number of binding sites = the number of valences
T
- Stem of monomer and lower parts of Y arms
- Responsible for the type and antigen-antibody reaction that occurs
- Constant region of heavy chain differs from one antibody class to the other
- Structure serves as a basis for distinguishing the 5 different classes: IgG, IgA, IgM, IgD and IgE
CONSTANT REGION
FC stands for
Fragment Constant
T or F
All of the antibodies have the same Fc region
T
- All of the antibodies have the same Fc region
- Mainly the one attached to the B cells or T cells
- For complement fixation, skin fixation and placental transfer
- No capability to bind the antibody
FC (FRAGMENT CONSTANT) REGION
_______________________
* First approximately ____ amino acids at the amino-terminal
end
* The remaining amino acids can typically be divided up into two or three or more constant regions with very similar constant regions with very similar sequences, designated CH1, CH2, and CH3 (constant heavy chain 1,2,3)
VARIABLE DOMAIN
* First approximately 110 amino acids at the amino-terminal
end
* The remaining amino acids can typically be divided up into two or three or more constant regions with very similar constant regions with very similar sequences, designated CH1, CH2, and CH3 (constant heavy chain 1,2,3)
Refers to the heavy chain that determine the Ig class
Isotype
