title: Immunomodulatory activity of met-enkephalin and its two potent analogs.
abstract: The effects of Met-enkephalin (Met-Enk), a delta receptor binding opioid peptide, and its more stable synthetic analogs, Tyr-D-Ala-Gly-MePhe-Met-NHC3H7-iso (1), Tyr-D-Ala-Gly-MePhe-Gly-NHC3H7-iso (2) and Tyr-D-Ala-Gly-MePhe-Gly-NHCH2C6H5 (3), on human T-cell transformation and natural killer (NK) cell cytotoxicity have been evaluated. Analogs 1 and 2 have been found to be as potent as Met-Enk in stimulating T-cell transformation and augmenting NK cell cytotoxicity. Analog 3 had no effect on T-cell transformation and NK cell cytotoxicity. Proliferative response was measured by 3H-thymidine uptake after 5 days of incubation. The kinetics of the T-cell transformation response (peak 5th day) is similar to those for in vitro T-cell responses to specific antigens rather than via polyclonal activation.
authors.affiliation: Department of Immunology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: K
authors.initials: K
authors.lastname: Bajpai
authors.forename: V K
authors.initials: VK
authors.lastname: Singh
authors.forename: S S
authors.initials: SS
authors.lastname: Agarwal
authors.forename: V C
authors.initials: VC
authors.lastname: Dhawan
authors.forename: T
authors.initials: T
authors.lastname: Naqvi
authors.forename: W
authors.initials: W
authors.lastname: Haq
authors.forename: K B
authors.initials: KB
authors.lastname: Mathur
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000595:Amino Acid Sequence; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives* / Q000276:immunology* / Q000494:pharmacology; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects; D008213:Lymphocyte Activation / Q000187:drug effects*; D008969:Molecular Sequence Data; D013601:T-Lymphocytes / Q000187:drug effects
chemical_list: D000276:Adjuvants, Immunologic; D004744:Enkephalin, Methionine