title: Differential effect of beta-endorphin on three human cytotoxic cell populations.
abstract: We have examined in vitro the effect of the proopiomelanocortin gene product, beta-endorphin (bE), on the cytotoxic activity of natural killer (NK) cells, lymphokine activated killer (LAK) cells and cytotoxic T-lymphocytes (CTL). Our studies show that bE reproducibly suppressed LAK cytotoxic activity in all donors tested. The effect of bE on the generation of CTL varied, and was negligible on CTL cytotoxic function. Our study also confirms the variable nature of the effects of bE on NK cytotoxicity. In all instances, the effects of bE were generally small, but could be blocked by opioid receptor antagonists, or by prior heat-inactivation of the peptide. The magnitude of the effects was greatest at low effector:target ratios in all of the three systems studied. These results support the emerging body of evidence that the neuroendocrine system may influence host defense mechanisms mediated by cytotoxic cells.
authors.affiliation: Psychoneuroimmunology Program, University of California, Los Angeles 90024.
authors.forename: F
authors.initials: F
authors.lastname: Chiappelli
authors.forename: N
authors.initials: N
authors.lastname: Yamashita
authors.forename: M
authors.initials: M
authors.lastname: Faisal
authors.forename: M
authors.initials: M
authors.lastname: Kemeny
authors.forename: R
authors.initials: R
authors.lastname: Bullington
authors.forename: L
authors.initials: L
authors.lastname: Nguyen
authors.forename: L T
authors.initials: LT
authors.lastname: Clement
authors.forename: J L
authors.initials: JL
authors.lastname: Fahey
mesh_terms: D000293:Adolescent; D000328:Adult; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects / Q000276:immunology; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008297:Male; D008875:Middle Aged; D015213:Neuroimmunomodulation / Q000187:drug effects; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology; D001615:beta-Endorphin / Q000494:pharmacology*
chemical_list: D001615:beta-Endorphin