Binding of immune complexes to IgA-sepharose 4B

A method for the determination and removal of circulating immune complexes in pathological sera was developed using human secretory or dimeric myeloma IgA covalently bound to Sepharose 4B. IgA-Sepharose 4B was able to selectively bind heat or antigen-aggregated human IgG (circulating immune complexes) but not monomeric IgG. The absorbent was also able to remove a very high proportion (95%) of circulating immune complexes from pathological sera as determined by a turbidimetric technique. An immunoradiometric assay for the direct measurement of circulating immune complexes is described. The assay uses IgA-Sepharose 4B as an absorbent (for the binding of IgG immune complexes from sera) and 125I-rabbit anti-IgG antibody (for the quantitation of IgG immune complexes bound to IgA-Sepharose 4B). The mean value obtained for pathological sera (27.1 +/- 0.9) was significantly higher than that of normal sera (4.8 +/- 0.5).

Related Concept Videos

Immunoglobulin-like Cell Adhesion Molecules01:31

Immunoglobulin-like Cell Adhesion Molecules

Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Immunoprecipitation01:20

Immunoprecipitation

Immunoprecipitation, or IP, is a widely used technique that employs protein-antibody interactions to isolate proteins or protein complexes in their native state for studying protein-protein interactions, quaternary structures, or supramolecular complexes. Various modifications of the technique, including chromatin IP, cross-linking IP, and fluorescence IP, are commonly used.
Chromatin Immunoprecipitation
Chromatin immunoprecipitation, also known as ChIP, is used to study protein-DNA or...
Immunofluorescence Microscopy01:12

Immunofluorescence Microscopy

A fluorescence microscope uses fluorescent chromophores called fluorochromes, which can absorb energy from a light source and then emit this energy as visible light. Fluorochromes include naturally fluorescent substances (such as chlorophylls) and fluorescent stains that are added to the specimen to create contrast. Dyes such as Texas red and FITC are examples of fluorochromes. Other examples include the nucleic acid dyes 4’,6’-diamidino-2-phenylindole (DAPI), and acridine orange.
The...
Immunocytochemistry and Immunohistochemistry01:22

Immunocytochemistry and Immunohistochemistry

Immunocytochemistry (ICC) and immunohistochemistry (IHC) are techniques that use antibodies to check for specific proteins or antigens in a sample. The technique was first published by Albert Coons in 1941 to detect the presence of pneumococcal antigen in tissue sections from mice infected with Pneumococcus. Immunocytochemistry helps localization of proteins or antigens in individual cells like blood cells, stem cells, etc., while immunohistochemistry does the same for tissue samples.
These...
Affinity Chromatography01:03

Affinity Chromatography

Affinity chromatography is a powerful technique extensively utilized for separating and purifying specific biomolecules from complex mixtures. It capitalizes on the highly selective binding between an analyte and its counterpart, such as antibody-antigen interactions. The counterpart is immobilized on the stationary phase, forming an affinity column. The stationary phase typically consists of solid support, such as agarose or porous glass beads, immobilizing the affinity ligand. The mobile...
Antibody Actions01:26

Antibody Actions

Antibodies, or immunoglobulins, are critical players in the immune system's arsenal against invading pathogens. Produced by B cells and plasma cells, their primary role is to detect and bind to specific antigens, molecules found on the surface of pathogens like bacteria or viruses. Beyond antigen recognition, antibodies perform several vital functions that contribute to immune defense.
Neutralization
Antibodies can bind to pathogens, preventing them from infecting host cells. This process...