title: Cytopathic effects of Moraxella bovis on cultured bovine neutrophils and corneal epithelial cells.
abstract: The effects of Moraxella bovis on the morphologic features of purified bovine neutrophils and bovine corneal epithelial cells were examined, using transmission and scanning electron microscopy and light microscopy. Within 2 minutes after incubation of bovine neutrophils with living M bovis, electron microscopic cellular changes included vacuolation, swelling, and loss of microplicae. Most of the neutrophils were lysed by 10 minutes of incubation. Human neutrophils phagocytosed the M bovis and remained intact, even after 30 minutes of incubation with the bacteria. Living M bovis killed bovine corneal epithelial cells in vitro. Sterile filtrates prepared from 6-hour shaker cultures of M bovis also killed bovine corneal epithelial cells, but the cytotoxic activity was less than that produced by the living bacteria. Cellular changes were first observed in specimens collected 1 hour after corneal cell monolayers were inoculated with sterile culture filtrates. The changes in these cells included pit-like lesions on the cellular surface, cellular separation, and vacuolation.
authors.affiliation: Department of Medicine, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: G M
authors.initials: GM
authors.lastname: Kagonyera
authors.forename: L W
authors.initials: LW
authors.lastname: George
authors.forename: R
authors.initials: R
authors.lastname: Munn
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D003315:Cornea / Q000382:microbiology* / Q000648:ultrastructure; D004848:Epithelium / Q000382:microbiology / Q000648:ultrastructure; D006801:Humans; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009016:Moraxella / Q000254:growth & development / Q000502:physiology*; D009504:Neutrophils / Q000382:microbiology* / Q000648:ultrastructure