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A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity
Published on: August 9, 2017
Effect of phytoncide from trees on human natural killer cell function.
Q Li1, M Kobayashi, Y Wakayama
1Department of Hygiene and Public Health, Nippon Medical School, Tokyo, Japan. qing-li@nms.ac.jp
International Journal of Immunopathology and Pharmacology
|January 16, 2010
Summary
Forest air, rich in phytoncides from hinoki cypress, boosts natural killer (NK) cell activity and anti-cancer proteins. This exposure also reduced stress hormones, suggesting a natural way to enhance immune function.
Area of Science:
- Environmental Medicine
- Immunology
- Human Health
Background:
- Forest environments enhance human natural killer (NK) cell activity and lymphocyte anti-cancer proteins.
- Increased NK activity from forest exposure persists for over 7 days.
Purpose of the Study:
- To investigate the effect of tree essential oils (phytoncides) on human immune function.
- To explore the role of phytoncide exposure in activating human NK cells.
Main Methods:
- Twelve healthy males stayed in a hotel exposed to hinoki cypress stem oil vapor (phytoncides).
- Blood and urine samples were analyzed for NK cell activity, lymphocyte markers, and stress hormones.
- Phytoncide concentrations in the air were measured.
Main Results:
- Phytoncide exposure significantly increased NK cell activity and the percentage of NK, perforin, and granzyme A/B-expressing cells.
- Exposure decreased T cell percentages and urinary adrenaline/noradrenaline levels.
- Phytoncides like alpha-pinene and beta-pinene were detected.
Conclusions:
- Phytoncide exposure from hinoki cypress oil can enhance human NK cell activity.
- Reduced stress hormone levels may contribute to increased NK cell activity.
- Phytoncides offer a potential avenue for immune system support.
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