Abstract |
Either activated neutrophils (PMNs) or nanomole amounts of reagent hydrogen peroxide (H2O2) were found to cause catalase-reversible suppression of concanavalin A (Con A)-stimulated human lymphocyte proliferation. Suppression required PMN activation and occurred with PMN/lymphocyte ratios found in peripheral blood. Inhibition by reagent H2O2 occurred with 10-40 nmol H2O2/1 X 10(6) lymphocytes, a noncytolethal amount which is produced readily by PMA-activated PMNs. Lymphoblasts recovered from suppressed cultures were two- to fourfold less sensitive than control lymphoblasts to a second exposure to H2O2. These relatively H2O2-resistant lymphoblasts also scavenge H2O2 at higher rates than do control lymphoblasts. Progeny lymphocytes from suppressed cultures contain an unusually high percentage of T helper cells with a concomitant decrease in T suppressors. These studies demonstrate a potential immunoregulatory role for phagocyte-released oxidants, especially H2O2, and suggest a possible additional mechanism to explain the excess of T helpers observed in situations of chronic inflammation.
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Authors | D C Zoschke, N D Staite |
Journal | Clinical immunology and immunopathology
(Clin Immunol Immunopathol)
Vol. 42
Issue 2
Pg. 160-70
(Feb 1987)
ISSN: 0090-1229 [Print] United States |
PMID | 2948748
(Publication Type: Journal Article)
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Chemical References |
- Antigens, Surface
- Concanavalin A
- Hydrogen Peroxide
- Catalase
- Tetradecanoylphorbol Acetate
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Topics |
- Antigens, Surface
- Catalase
(pharmacology)
- Cell Survival
- Cells, Cultured
- Concanavalin A
(pharmacology)
- Depression, Chemical
- Drug Resistance
- Humans
- Hydrogen Peroxide
(metabolism, pharmacology)
- Leukocyte Count
- Lymphocyte Activation
(drug effects)
- Neutrophils
(drug effects, immunology)
- Phenotype
- T-Lymphocytes, Helper-Inducer
(drug effects, immunology)
- T-Lymphocytes, Regulatory
(drug effects, immunology)
- Tetradecanoylphorbol Acetate
(pharmacology)
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