Immunoglobulins antigenic markers

Antigenic markers (allotypes) of immunoglobulin molecules were almost simultaneously reported for human and rabbit antibodies. Oudin (1956) observed that rabbit antibodies themselves elicited precipitating antibodies when they were injected into certain other rabbits. Oudin named the phenomenon allotypy and the antigenic determinants on the immunoglobulin molecules were called allotypes. At the same... 

Cloning can also be performed using a FACS. Although a powerful technique, it is available to only a limited number of laboratories because of the cost of the equipment. Antigen coupled to a fluorescent marker is incubated with the cells. Cells with surface immunoglobulins of relevant specificity can then be isolated and sorted into individual tissue culture wells. 

Immunoblotting techniques involve the identification of a protein target via antigen-antibody-specific reactions. Proteins are typically separated by electrophoresis in polyacrylamide gels, and then transferred ( blotted ) onto chemically resilient membranes (e.g., nitrocellulose, polyvinylidene difluoride) where they bind in the pattern they took in the gel. The membrane is overlaid with a primary antibody directed to the specific target, then with a secondary antibody (anti-immunoglobulin) labeled with radioisotopes, enzymes or other marker compounds. 

A single individual may produce a population of antibody specificities, an antibody repertoire, which is a reflection of all the B cell clones (lymphocyte repertoire) capable of immunoglobulin (Ig) synthesis and secretion in response to antigenic stimulation, but also in absence of exposure to environmental pathogens [48, 49]. Natural antibodies, in fact, are germ line-encoded molecules produced by a distinct population of peritoneal B cells, bearing the cell surface marker CD 5 and are present in the sera and interstitial fluids of healthy individuals [49-51]. 

This class includes Carnoy s, Methacarn and others. They have been used for IHC purposes primarily in order to try to avoid the loss of antigenicity caused by excessive formalin fixation, or for monoclonal antibodies that reacted against an epitope destroyed by formalin. These fixatives typically found most of the application in looking at lymphocytes using CD-specific markers, and in looking for immunoglobulins such as IgG, A, and M. 

Antibodies to polysaccharide antigens such as dextrans and levans produced in humans, while heterogeneous, often show restricted heterogeneity as shown by acrylamide gel electrophoresis (Yount et al., 1968), isoelectric focusing patterns (Cisar et al., 1975), starch gel electrophoresis of the separated polypeptide chains (Edelman and Kabat, 1964) and in possessing fewer genetic markers than found on the total immunoglobulin of the same individual (Allen et al., 1964 Yount et al., 1968). 

CD4. A cell surface antigen belonging to the immunoglobulin superfamily of molecules. Marker of T helper cells. As an adhesion molecule, it interacts with the non-polymorphic part of -MHC class II gene product. 

While no QDs have been approved for clinical use to date, they have proven useful in both in vitro and in vivo diagnostics in animal studies. In vitro, QDs have begun to replace traditional fluorescent dyes due to the advantages discussed above. Wu a demonstrated this by the conjugation of immunoglobulin (IgG) and streptavidin to QDs with different emission spectra and showed how QDs can be used as a superior marker for both nuclear antigens and microtubules relative to Alexa 488 dye. 

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