Presence of surfactant lamellar bodies in normal and diseased sinus mucosa.
BACKGROUND
Pulmonary surfactant originates from phospholipid lamellar bodies secreted from the type II epithelial cell of the alveolus. In the lower airway, surfactant optimizes surface tension and oxygen exchange, decreases mucus viscosity and aids in mechanical elimination of inhaled pathogens. In addition to the lung, lamellar bodies have been identified in many other cell types throughout the human body. However, no prior studies have identified lamellar bodies in human sinus mucosa.


OBJECTIVE
We performed ultrastructural studies to assess whether lamellar bodies are present in the human sinus in a variety of diseased and normal epithelium.


METHODS
We biopsied sinus mucosa from 5 subjects, 1 each with allergic fungal sinusitis, eosinophilic mucin rhinosinusitis, cystic fibrosis, frontal sinus mucocele, and cerebrospinal fluid leak (healthy control). Mouse lung served as a positive control. Specimens were prepared using ferrocyanide-reduced osmium tetroxide and thiocarbohydrazide for fixation (R-OTO method) to avoid extraction of phospholipids during dehydration and were viewed with transmission electron microscopy.


RESULTS
We identified lamellar bodies in the sinus mucosa of all patients. Additionally, preservation of mouse lung lamellar bodies confirms that the R-OTO method is a valid technique to preserve these structures.


CONCLUSIONS
We describe a simpler, faster technique for identification of cellular phospholipid components than those used previously. Definitive identification of these lamellar bodies within ciliated pseudostratified epithelium of the upper airway indicates that surfactant may have a role in sinus function and pathophysiology.
Woodworth
Bradford A
BA
Department of Otolaryngology, Head and Neck Surgery, Medical University of South Carolina, Charleston, SC 29425, USA.
Smythe
Nancy
N
Spicer
Samuel S
SS
Schulte
Bradley A
BA
Schlosser
Rodney J
RJ
D000818:Animals; D002559:Cerebrospinal Fluid Rhinorrhea / Q000473:pathology; D003550:Cystic Fibrosis / Q000473:pathology; D003594:Cytoplasmic Granules / Q000648:ultrastructure*; D004802:Eosinophilia / Q000473:pathology; D004847:Epithelial Cells / Q000648:ultrastructure; D005626:Frontal Sinus / Q000473:pathology; D006801:Humans; D008168:Lung / Q000648:ultrastructure; D051379:Mice; D046529:Microscopy, Electron, Transmission; D009077:Mucins / Q000032:analysis; D009078:Mucocele / Q000473:pathology; D009181:Mycoses / Q000473:pathology; D010254:Paranasal Sinus Diseases / Q000473:pathology*; D010256:Paranasal Sinuses / Q000648:ultrastructure*; D010743:Phospholipids / Q000032:analysis; D011663:Pulmonary Surfactants / Q000032:analysis*; D012130:Respiratory Hypersensitivity / Q000382:microbiology / Q000473:pathology; D020545:Respiratory Mucosa / Q000648:ultrastructure*; D012220:Rhinitis / Q000473:pathology; D012852:Sinusitis / Q000382:microbiology / Q000473:pathology; D016707:Tissue Fixation / Q000379:methods
D009077:Mucins; D010743:Phospholipids; D011663:Pulmonary Surfactants