Stachybotrys chartarum spore extracts and their effects on surfactant protein expression and surfactant quantity and quality in fetal rat lung epithelial cells

Abstract

S. chartarum spores are prevalent in buildings affected by flooding and have been tied to occurrences of pulmonary hemosiderosis in infants in Cleveland, Ohio, several years ago. Rationale: Past studies have focused on the effects of S. chartarum spores on surfactant in terms of composition and quantity and very little has been done to investigate the effects of S. chartarum extracts on surfactant protein expression in the fetal lung. Methods: Spore extracts were incubated with cultures of human lung A549 cells, fetal rat lung type II and fibroblast cells. MTT formazan assays analyzed cell viability. The expression of surfactant protein A and surfactant protein B was assessed using western blotting results. Captive bubble surfactometry investigated the quality of surfactant in terms of surface tension and bubble volume. Electron microscopy examined changes in cellular structure of treated cells. Conclusions: Exposure to S. chartarum extracts had negative effects on cell viability, expression of surfactant proteins A and B and the production and quality of pulmonary surfactant. Spore associated changes were apparent in the lamellar bodies of fetal rat lung alveolar type II, and human A549 cells.