1. Immunomodulatory effects of pulmonary surfactant on natural killer cell and antibody-dependent cytotoxicity.
- Author
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Wilsher, Margaret L., Hughes, D. A., and Haslam, Patricia L.
- Subjects
STEROIDS ,BIOMOLECULES ,PHOSPHOLIPIDS ,LYMPHOCYTES ,LIPIDS ,IMMUNOMODULATORS - Abstract
Alveolar natural killer (NK) cells are functionally weak compared to their blood and interstitial counterparts. Having previously demonstrated that pulmonary surfactant suppresses lymphocyte responses to a variety of stimuli we sought in this study to determine if surfactant exerts a similar suppressive effect on cytotoxic function. Lipids were purified from the bronchoalveolar lavage (BAL) fluid from normal human volunteers. Human peripheral blood lymphocytes (n= 10 subjects) were cultured overnight in the presence or absence of purified BAL lipids (0.2 mg/ml), or pure preparations of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylglycerol (PG) (0.4 mg/ml). Standard NK and antibody-dependent cytotoxicity (ADCC) assays were performed using K562 and Chang target cells. The pooled BAL lipids significantly suppressed both NK (P < 0.01) and ADCC (P = 0.01) activity in a dose-dependent manner. Whereas pure PC did not exert a significant effect, PG significantly suppressed (P < 0.01) and PE significantly enhanced (P < 0.01) both cytotoxic functions. There was no change in the expression of leu 7 or 11 b antigens by lymphocytes after culture in BAL lipids. These results suggest that under normal circumstances pulmonary surfactant may suppress alveolar cytotoxic responses but that imbalances in the phospholipid profile might affect this immunoregulatory properly. [ABSTRACT FROM AUTHOR]
- Published
- 1988