Effect of synthetic beta-endorphin-like peptide immunorphin on human T lymphocytes

• Published in: Biochemistry (Moscow) Vol. 67; no. 3; pp. 357 - 363
• Main Authors: Navolotskaya, E V, Malkova, N V, Zargarova, T A, Lepikhova, T N, Krasnova, S B, Lipkin, V M
• Format: Journal Article
• Language: English
• Published: United States 01.03.2002
• Subjects: beta-Endorphin - pharmacology; Binding, Competitive; Cell Division - drug effects; Cell Transformation, Neoplastic; Concanavalin A - pharmacology; Enkephalin, Methionine - pharmacology; Humans; Immunoglobulin Constant Regions; Immunoglobulin G; Immunoglobulin gamma-Chains; Immunoglobulin Heavy Chains; Iodine Radioisotopes - chemistry; Lymphocyte Activation; Naloxone - pharmacology; Narcotic Antagonists - pharmacology; Oligopeptides - chemical synthesis; Oligopeptides - metabolism; Oligopeptides - pharmacology; Peptide Fragments - pharmacology; Receptors, Opioid - metabolism; T-Lymphocytes - drug effects; T-Lymphocytes - metabolism
• ISSN: 0006-2979; 1608-3040
• DOI: 10.1023/A:1014844718799

Beta-endorphin and the synthetic beta-endorphin-like decapeptide Ser-Leu-Thr-Cys-Leu-Val-Lys-Gly-Phe-Tyr (referred to as immunorphin), corresponding to the sequence 364-373 of the CH3 domain of human immunoglobulin G heavy chain, were shown to stimulate concanavalin A-induced proliferation of T lymphocytes from the blood of healthy donors. [Met(5)]Enkephalin and the antagonist of opioid receptors naloxone examined in parallel were inactive. The stimulating effect of beta-endorphin and immunorphin on T lymphocyte proliferation is not inhibited by naloxone. Studies on receptor binding of (125)I-labeled immunorphin to T lymphocytes revealed that it binds with high affinity to naloxone-insensitive receptors (K(d) = 7.0 +/- 0.3 nM). Unlabeled immunorphin completely inhibits (125)I-labeled beta-endorphin specific binding to naloxone-insensitive receptors on T lymphocytes (K(i) = 0.6 +/- 0.1 nM). Thus, beta-endorphin and immunorphin interact with common naloxone-insensitive receptors on T lymphocytes.