Related Experiment Video
Updated: Jul 26, 2026

Generation of Recombinant Human IgG Monoclonal Antibodies from Immortalized Sorted B Cells
Published on: June 5, 2015
Anti-pyruvate dehydrogenase complex-E2 antibody immunoglobulin class switch from IgM to IgG in long-term follow-up
Hiroshi Miyakawa1, Kentaro Kikuchi, Eriko Kitazawa
1Fourth Department of Internal Medicine, Teikyo University School of Medicine. 3-8-3 Mizonokuchi, Takatsu-ku, Kawasaki-shi, 213-8507, Kanagawa, Japan
Abstract:
Antibody immunoglobulin class switching from IgM to IgG is usually observed in acute viral infections. However, in autoimmune diseases, the autoantibody immunoglobulin class switch from IgM to IgG has been observed only rarely, and the clinical relevance of this immune phenomenon remains unclear. In this report, anti-pyruvate dehydrogenase complex (PDC)-E2 antibody immunoglobulin class switching was followed in two patients with primary biliary cirrhosis (PBC). IgG and IgM anti-PDC-E2 antibodies were examined by an originally enzyme-linked immunosorbent assay and by immunoblot using human recombinant PDC-E2 protein. In both patients, serum IgG and IgM anti-PDC-E2 antibodies could not be detected at initial admission. However, IgM antibody was subsequently detected, and IgG antibody appeared several years thereafter.
Related Concept Videos
Antibody Structure
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibody Structure and Classes
The basic structure of an antibody consists of four protein chains: two identical heavy chains and two identical light chains. These chains are held together by disulfide bonds and other non-covalent interactions, forming a Y-shaped structure.
Gastritis-II: Pathophysiology
In acute gastritis, the gastric mucosa becomes swollen and red and undergoes superficial erosion. Superficial ulceration may lead to bleeding.
In chronic gastritis, persistent or repeated insults lead to chronic inflammatory changes and, eventually, thinning or atrophy of the gastric tissue.
Gastritis can stem from various causes, each...

