title: Effects of morphine on the phenotypic expression of cell surface markers on murine lymphocytes.
abstract: There is a growing literature indicating that opioid abuse by human addicts and opioid administration to animals have profound effects on the immune system. In the present study, implantation of morphine pellets in mice was associated with reduced phenotypic expression of the cell surface antigens specific to T-lymphocytes and to helper and cytotoxic/suppressor T-lymphocyte subtypes. The effect of morphine, as measured by flow cytometry using monoclonal antibodies specific for antigens expressed by these cells, was dose-dependent. The decrease in expression of antigens was apparent as early as 24 h after morphine pellet implantation and continued for 3 days. In addition, a time-dependent increase in the expression of these antigens was observed in placebo- and morphine-treated mice, suggesting that the pellets had a small antigenic effect. However, at all times studied, morphine-treated mice had fewer cells expressing the antigens than placebo-treated mice. Our results provide additional evidence that the use of opioids by IV drug abusers compromises their immune function.
authors.affiliation: Neuropharmacology Laboratory, National Institute on Drug Abuse, Baltimore, MD 21224.
authors.forename: A S
authors.initials: AS
authors.lastname: Kimes
authors.forename: W J
authors.initials: WJ
authors.lastname: Smith
authors.forename: C J
authors.initials: CJ
authors.lastname: Winchell
authors.forename: E D
authors.initials: ED
authors.lastname: London
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000235:genetics*; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007958:Leukocyte Count / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009020:Morphine / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects; D010641:Phenotype; D013154:Spleen / Q000033:anatomy & histology / Q000187:drug effects; D016176:T-Lymphocyte Subsets / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology; D013997:Time Factors
chemical_list: D000954:Antigens, Surface; D009020:Morphine