Augmentation of natural cytotoxicity by leucine enkephalin in cultured peripheral blood mononuclear cells from patients infected with human immunodeficiency virus

Clin Immunol Immunopathol. 1989 Jun;51(3):386-95. doi: 10.1016/0090-1229(89)90036-6.

Abstract

Natural Killer (NK) activity of lymphocytes from acquired immunodeficiency syndrome (AIDS) patients is frequently below normal and declines as disease progresses. We studied the potential of leucine enkephalin (leu-enkephalin) to restore this immune parameter by incubating nylon wool nonadherent mononuclear cells from 14 patients in the presence or absence of leu-enkephalin, and measuring NK cytolysis in a standard 51Cr release assay. The NK activity of human immunodeficiency virus antibody positive (HIV+) individuals with some remaining NK lytic ability was significantly augmented by leu-enkephalin concentrations of 10(-10) and 10(-8) M (n = 7). HIV+ patients with no measurable basal level of NK activity (n = 3) were not responsive to stimulation with leu-enkephalin. Human immunodeficiency virus antibody negative (HIV-) individuals (n = 4) responded in a pattern similar to normals. In addition, naloxone, an antagonist of alkaloid and peptide opiates including leu-enkephalin, displayed the properties of an antagonist/agonist, reflecting the immunoregulatory capacities of the endogenous opiate system.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acquired Immunodeficiency Syndrome / immunology*
  • Adjuvants, Immunologic / pharmacology*
  • Antigens, Surface / analysis
  • Cells, Cultured
  • Cytotoxicity, Immunologic / drug effects*
  • Dose-Response Relationship, Immunologic
  • Enkephalin, Leucine / pharmacology*
  • Humans
  • Killer Cells, Natural / drug effects*
  • Killer Cells, Natural / immunology
  • Leukocytes, Mononuclear / classification
  • Phenotype

Substances

  • Adjuvants, Immunologic
  • Antigens, Surface
  • Enkephalin, Leucine