title: Myelopeptide-1 blocks the T-suppressor activity.
abstract: The immunoregulatory properties of two myelopeptides (MPs) [Phe-Leu-Gly-Phe-Pro-Thr (MP-1) and Leu-Val-Val-Tyr-Pro-Trp (MP-2)] were studied. The antibody production-stimulating activity was determined in the culture of lymph node cells (LNC) obtained from mice on the 4th day of the secondary immune response to sheep red blood cells (SRBC). T suppressors were induced in mouse spleen cell (SC) culture by incubation with concanavalin A (Con A) for 48 h. Immune LNC were cultured alone or with T suppressors in the presence or absence of MPs. After cultivation, the immune response was estimated by enumeration of indirect antibody forming cells (AFC). MP-1, but not MP-2, increased the number of AFC and abolished Con A induction of T suppressors in SC suspensions. MP-1 also fully blocked and MP-2 only partly decreased the inhibitory effect of T suppressors in the culture of immune LNC. Immunoregulatory peptide MP-1 may participate in regulation of the antibody response and in development of some states of immunological tolerance.
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
authors.forename: R V
authors.initials: RV
authors.lastname: Petrov
authors.forename: A A
authors.initials: AA
authors.lastname: Mikhailova
authors.forename: E A
authors.initials: EA
authors.lastname: Kirilina
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation / Q000187:drug effects; D002478:Cells, Cultured; D003208:Concanavalin A; D005260:Female; D007155:Immunologic Factors / Q000494:pharmacology*; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008969:Molecular Sequence Data; D009842:Oligopeptides; D010455:Peptides / Q000494:pharmacology*; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology*
chemical_list: D007155:Immunologic Factors; D009842:Oligopeptides; D010455:Peptides; D003208:Concanavalin A; C048617:myelopeptides