       Document 0174
 DOCN  M95B0174
 TI    Synergistic effect of cortisol and HIV-1 envelope peptide on the NK
       activities of normal lymphocytes.
 DT    9511
 AU    Nair MP; Schwartz SA; State University of New York at Buffalo, USA.
 SO    Brain Behav Immun. 1995 Mar;9(1):20-30. Unique Identifier : AIDSLINE
       MED/95345520
 AB    In order to examine the potential role of stress hormones and
       circulating HIV-1-derived products in the progression of HIV infections,
       we developed an in vitro model system that investigates the effects of
       cortisol and HIV soluble gene products on the natural killer cell
       activity of normal lymphocytes. The system employs a 4-h 51Cr release
       assay and K562- and LAV-infected 8E5/LAV target cells. Direct addition
       of cortisol at 0.05, 0.1, and 0.2 microgram/ml or the HIV recombinant
       peptide, env-gag, at 1, 10, and 50 ng/ml separately to the mixture of
       effector and prelabeled target cells did not produce any significant
       immunoregulatory effects on NK cell activity against either target.
       However, cortisol or env-gag at concentrations that did not produce any
       inhibitory effect on NK activity when used separately, manifested
       significant inhibitory effects when added in combination. Suppression
       was evident at concentrations as low as 1 ng/ml of env-gag and 0.05
       microgram/ml of cortisol and was observed at different effector:target
       cell ratios. Suppression was not caused by nonspecific toxicity of
       cortisol or HIV peptides when added in combination to the effector cells
       nor was due to decreased susceptibility of targets to lysis by effector
       cells. A non-HIV viral antigen (Rubeola virus) and another HIV-1
       envelope-derived sequence (env 578-608 aa) were used as controls
       separately or in combination with cortisol and did not produce
       significant inhibition thus demonstrating the specificity of
       env-gag-induced inhibition. The synergistic inhibitory effect of
       cortisol- and HIV-derived soluble products in patients with HIV
       infections are consistent with a model that proposes that stress and
       circulating HIV-1-derived products may be involved in the progression of
       HIV infections.
 DE    Adult  Cells, Cultured  Cytotoxicity, Immunologic/DRUG EFFECTS
       Dose-Response Relationship, Immunologic  Drug Synergism  Feedback  Gene
       Products, gag/PHARMACOLOGY  Human  Hydrocortisone/*PHARMACOLOGY
       HIV-1/*IMMUNOLOGY  Immune Tolerance/DRUG EFFECTS  Killer Cells,
       Natural/*DRUG EFFECTS/IMMUNOLOGY  Male  Support, Non-U.S. Gov't
       Support, U.S. Gov't, P.H.S.  Tumor Cells, Cultured  Viral Envelope
       Proteins/PHARMACOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

