title: Effect of methionine enkephalin on natural killer cell and cytotoxic T lymphocyte activity in mice infected with influenza A virus.
abstract: Methionine enkephalin (Met-Enk) was evaluated for efficacy as an immune activator and potential therapeutic agent in influenza A/NWS/33 (H1N1) viral infections in female BALB/C mice. Influenza infection was induced intranasally with an approximate 90% lethal dose of virus and mice were treated intraperitoneally with doses of 10, 3 and 1 mg/kg/day, with treatments given 24 h pre-, 24 h post- and 72 h post-virus exposure. Splenocytes were assayed for natural killer cell (NK) and cytotoxic T lymphocyte (CTL) activity at time periods 76, 96 and 120 h post virus exposure. The 10 mg/kg dosage level significantly increased both CTL and NK activity at all time periods assayed. Other treatment schedules included single doses of 20, 10 and 3 mg/kg/day Met-Enk at either 24 h post- or 72 h post-virus exposure, with highly significant increases in NK and CTL activity noted after the latter treatment. The results of this study demonstrate the immunomodulatory effects of Met-Enk on NK and CTL in influenza infected mice and suggest a potential for therapeutic applications.
authors.affiliation: Department of Biology, Utah State University, Logan 84322-6895, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Burger
authors.forename: R P
authors.initials: RP
authors.lastname: Warren
authors.forename: J H
authors.initials: JH
authors.lastname: Huffman
authors.forename: R W
authors.initials: RW
authors.lastname: Sidwell
mesh_terms: D000818:Animals; D003601:Cytotoxicity Tests, Immunologic; D004744:Enkephalin, Methionine / Q000494:pharmacology*; D005260:Female; D009980:Influenza A virus / Q000276:immunology; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000821:virology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects* / Q000276:immunology
chemical_list: D004744:Enkephalin, Methionine