Production of Antibodies to the α7-Subunit of Human Acetylcholine Receptor with the Use of Immunoactive Synthetic Peptides

O. M. Volpina , # M. A. Titova , D. O. Koroev , T. D. Volkova , M. B. Oboznaya , M. N. Zhmak , T. A. Aleekseev , and V. I. Tsetlin

# Phone: +7 (095) 336-5777; e-mail: volpina@ibch.ru

Shemyakin--Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , ul. Miklukho-Maklaya 16/10, Moscow , 117997 Russia

Received June 30, 2005; in final form, July 13, 2005

Abstract: Potential B epitopes and T-helper epitopes in the N-terminal extracellular domain of the α7-subunit of human acetylcholine receptor (AChR) were theoretically calculated in order to reveal peptides that can induce the formation of specific antibodies to this domain. Four peptides structurally corresponding to four α7-subunit regions containing 16--23 aa and three of their truncated analogues were synthesized. Rabbits were immunized with both free peptides and protein conjugates of their truncated analogues, and a panel of antibodies to various exposed regions of the N-terminal extracellular domain of the AChR α7-subunit was obtained. All of the four predicted peptides were shown to induce the production of antipeptide antibodies in free form, without conjugation with any protein carrier. The free peptides and the protein conjugates of truncated analogues induced the formation of almost equal levels of antibodies. Most of the obtained antisera contained antibodies that bind to the recombinant extracellular N-terminal domain of the rat AChR α7-subunit and do not react with the analogous domain of the α1-subunit of the ray Torpedo californica AChR.

Key words: acetylcholine receptor, α7-subunit, B epitopes, T-helper epitopes, synthetic peptides

Russian Journal of Bioorganic Chemistry 2006, 32 (2):154-159