REVIEW: The Second Life of Antibodies

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E. V. Navolotskaya

Branch of Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, pr. Nauki 6, 142290 Pushchino, Moscow Region, Russia; fax: +7 (4967) 330-527; E-mail: navolotskaya@fibkh.ru; elenanavolots@gmail.com

Received May 22, 2013; Revision received July 25, 2013

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Antibodies (immunoglobulins, Ig) are used by the immune system to identify and neutralize foreign objects and are responsible for antigen-binding and effector functions. Immunoglobulin G (IgG) is the major serum immunoglobulin of a healthy human (~75% of the total Ig fraction). The discovery in 1970 of the endogenous tetrapeptide tuftsin (Thr-Lys-Pro-Arg, fragment 289-292 of the C_H2-domain of the heavy (H) chain of IgG), possessing both immunostimulatory and neurotrophic activities, was an impetus for the search for new biologically active peptides of immunoglobulin origin. As a result, fragments of the H-chain of IgG produced as a result of enzymatic cleavage of IgG within the antigen–antibody complex were discovered, synthesized, and studied. These fragments include rigin (341-344), immunorphin (364-373), immunocortin (11-20), and peptide p24 (335-358) and its fragments. In this review the properties of these peptides and their role in regulating the immune response are analyzed.

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KEY WORDS: antibodies, peptides, receptors, immune system

DOI: 10.1134/S0006297914010015

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