Pulmonary surfactant phospholipids modulate priming of rabbit alveolar macrophages for oxidative responses

• Published in: Journal of leukocyte biology 1992-04, Vol.51 (4), p.379-385
• Main Authors: Hayakawa, Hiroshi, Giridhar, Girish, Myrvik, Quentin N., Kucera, Louis
• Format: Article
• Language: English
• Subjects: alveolar macrophages; Animals; Biological and medical sciences; chemiluminescence; Fatty Acids - pharmacology; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Glycerylphosphorylcholine - pharmacology; Immunobiology; Macrophage-Activating Factors - pharmacology; Macrophages, Alveolar - physiology; Male; Monocytes, macrophages; Myeloid cells: ontogeny, maturation, markers, receptors; Phagocytosis - drug effects; Phorbol 12,13-Dibutyrate - pharmacology; phospholipids; Phospholipids - pharmacology; priming; pulmonary surfactant; Pulmonary Surfactants - physiology; Rabbits; Respiratory Burst - drug effects; Serum Albumin, Bovine - chemistry; Tetradecanoylphorbol Acetate - pharmacology; Zymosan - pharmacology
• ISSN: 0741-5400; 1938-3673
• DOI: 10.1002/jlb.51.4.379

We investigated the effect of individual phospholipids contained in pulmonary surfactant (PS) on the macrophage‐activating factor (MAF)‐induced priming of rabbit alveolar macrophages (AMs) for oxidative responses elicited by phorbol myristate acetate (PMA) or opsonized zymosan (Op‐Zym). AMs were incubated with MAF with or without phospholipids for 18 h. After incubation, oxidative responses were elicited with PMA (0.5 μg/ml) or Op‐Zym (250 μg/ml) and monitored by chemiluminescence (GL) assays. The data indicate that natural surfactant inhibited MAF‐induced priming of rabbit AMs for PMA‐ or Op‐Zym‐elicited oxidative responses. Artificial surfactant inhibited PMA‐elicited CL responses but enhanced Op‐Zym‐elicited GL responses. Individual phospholipids differed in modulative activities. Dioleoyl phosphatidylcholine (DOPC), dipalmitoyl phosphatidylglycerol (DPPG), and phosphatidylinositol (PI) inhibited MAF‐induced priming when the oxidative responses were elicited with PMA. Whereas DPPG inhibited Op‐Zym‐elicited oxidative responses, dipalmitoyl phosphatidylcholine (DPPC) and DOPC primed AMs for increased Op‐Zym‐elicited oxidative responses. DOPC did not affect the binding of phorbol dibutyrate to AMs, which suggests that reduced cell binding of phorbol ester was not responsible for the inhibition of PMA‐elicited oxidative responses in AMs treated with DOPC. Similarly, DPPC, DOPC, and DPPG did not affect the number of zymosan particles phagocytosed by AMs compared to the control, which suggested that enhanced or reduced Op‐Zym‐elicited oxidative responses by phospholipids were not due to altered phagocytic activity of AMs. In conclusion, our data indicate that individual surfactant phospholipid differently modulates priming of AMs for oxidative responses, and the effect of individual phospholipids does not account for the effect of complete PS on priming of AMs.