title: Fine structure of bacterial adhesion to the epithelial cell membranes of the filiform papillae of tongue and palatine mucosa of rodents: a morphometric, TEM, and HRSEM study.
abstract: The palatine mucosa and filiform papillae of the dorsal tongue mucosae of rodents were examined using transmission electron microscopy (TEM) and high resolution scanning electron microscopy (HRSEM). In the HRSEM method, the samples were fixed in 2% osmium tetroxide, dehydrated in alcohol, critical point-dried, and coated with gold-palladium. In addition, the HRSEM technique was used for morphometric analysis (length, width, and length/width ratio of cocci and bacilli). For the TEM method, the tissues were fixed in modified Karnovsky solution (2.5% glutaraldehyde, 2% formalin in 0.1M sodium phosphate buffer, pH 7.4) and embedded in Spurr resin. The results demonstrated that there are thick polygonal keratinized epithelial cells where groups of bacteria are revealed in three-dimensional images on the surface of filiform papillae in these animals. The bacterial membranes are randomly attached to the microplicae surface of epithelial cells. Morphometrics showed higher values of length and width of cocci in newborn (0 day) as compared to newborn (7 days) and adults animals, the bacilli showed no differences in these measurements. At high magnification, the TEM images revealed the presence of glycocalyx microfilaments that constitute a fine adhesion area between bacterial membranes and the membranes of epithelial microplicae cells. In conclusion, the present data revealed the fine fibrillar structures of bacteria that facilitate adhesion to the epithelial cell membranes of the oral cavity and morphometric changes in newborn (0 day) rats as compared with other periods.
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Faculty of Veterinary Medicine and Animal Science, Department of Surgery, University of São Paulo, São Paulo, Brazil.
authors.forename: Ii-Sei
authors.initials: IS
authors.lastname: Watanabe
authors.forename: Koichi
authors.initials: K
authors.lastname: Ogawa
authors.forename: Diego Pulzatto
authors.initials: DP
authors.lastname: Cury
authors.forename: Fernando José
authors.initials: FJ
authors.lastname: Dias
authors.forename: Marcia Consentino Kronka
authors.initials: MC
authors.lastname: Sosthenes
authors.forename: João Paulo Mardegan
authors.initials: JP
authors.lastname: Issa
authors.forename: Mamie Mizusaki
authors.initials: MM
authors.lastname: Iyomasa
mesh_terms: D000818:Animals; D001419:Bacteria / Q000378:metabolism; D001422:Bacterial Adhesion / Q000502:physiology*; D002462:Cell Membrane / Q000382:microbiology; D004847:Epithelial Cells / Q000382:microbiology; D005881:Gingiva / Q000382:microbiology*; D019276:Glycocalyx / Q000378:metabolism; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D009061:Mouth Mucosa / Q000382:microbiology*; D014066:Palatine Tonsil / Q000382:microbiology*; D051381:Rats; D017208:Rats, Wistar; D014059:Tongue / Q000382:microbiology*
keywords: HRSEM; TEM; bacteria; epithelial cell; rodents