In Vitro Studies on the Role of Zinc Oxide in the Development of <i>Aspergillus Fumigatus</i> Biofilm on Nasal Epithelial Cells

Abstract

Background and Objectives Fungal biofilm is commonly found in non-invasive fungal rhinosinusitis. Previous endodontic maxillary teeth treatments have increased fungus ball development in the maxillary sinus. We sought to evaluate the effects of zinc oxide (ZnO), the main component of endodontic sealers, on developing the <i>Aspergillus fumigatus</i> biofilms on primary human nasal epithelial cells.Subjects and Method Primary human nasal epithelial cells were cultured with <i>A. fumigatus</i> spores with (1 and 3 µg/mL) or without ZnO for 72 h. Interleukin (IL)-6, IL-8, and transforming growth factor (TGF)-β1 levels in cultural supernatant were determined by enzyme linked immunosorbent assay. ZnO’s effects on the formation of <i>A. fumigatus</i> biofilm were determined using crystal violet, safranin, concanavalin A staining, and confocal scanning laser microscopy.Results IL-6, IL-8, and TGF-β1 protein levels in primary human nasal epithelial cells increased significantly by <i>A. fumigatus</i> exposure. During coculturing with ZnO and <i>A. fumigatus</i>, biofilm dry weight, crystal violet, safranin, and concanavalin A staining intensity increased with time. On the other hand, ZnO did not enhance <i>A. fumigatus</i> biofilm formation.Conclusion <i>A. fumigatus</i> biofilm formation increased in the presence of primary human nasal epithelial cells. However, in vitro study, ZnO alone did not influence or aggravate biofilm formation in sinonasal mucosa.