Antibody Classes

Abstract

Antibodies are glycoproteins belonging to the immunoglobulin family. The immunoglobulins have a common four‐chain structure (two identical light chains and two identical heavy chains) and they can be divided into different classes (and subclasses) according to the isotype of the heavy chain. The heavy chain isotype will confer different structural and functional properties on each antibody class, so that each isotype will occupy a specific site in the body and have a specific role to play in the immune system.

Keywords: immunoglobulin classes; immunoglobulin subclasses; immunoglobulin structure; immunoglobulin function; immunoglobulin physico‐chemical properties

Figure 1.

Structure of the basic four‐chain unit of a human antibody molecule: (a) schematic structure and (b) spacefill model of the crystal structure of an intact human IgG1 (PDB code 1IGY).

Figure 2.

Polypeptide chain structures of the human antibody classes and subclasses: (a) IgG subclasses; (b) IgA subclasses, dimeric IgA and secretory IgA; (c) IgM; (d) IgE and (e) IgD.

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Wingren, Christer, Alkner, Ulf, and Hansson, Ulla‐Britt(Sep 2005) Antibody Classes. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0003985]