title: Molecular and ultrastructural studies of the fibrotic lesions of bovine focal proliferative fibrogranulomatous panniculitis (Lechiguana).
abstract: This work aimed to investigate some aspects related to the pathogenicity of Lechiguana, a bovine fibroproliferative lesion characterized by rapid collagen accumulation. Light and transmission electron microscopy and in situ hybridization studies were performed in order to elucidate the fibrogenic activity of this lesion. The characterization of fibroblastic plasticity in the lesion was done by immunohistochemical study for alpha-smooth-muscle cell actin. The ovoid-shaped cells presented positive reaction for alpha-smooth-muscle cell actin in their cytoplasm and, at the electron-microscopic level demonstrated basal lamina-like material adjacent to the external surface and collagen fibrils that corresponded to a cell population phenotypically similar to the myofibroblast. We also investigated alpha1 collagen type I mRNA at different times of evolution of Lechiguana lesions, using isotopic and non-isotopic in situ hybridization. The results strongly suggest the involvement of a myofibroblast-like cell population that expresses mRNA for type I collagen and is probably associated with the increase of collagen deposition.
authors.affiliation: Department of Epidemiology and Public Health, Rural Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. gandrade@ufrrj.br
authors.forename: G B
authors.initials: GB
authors.lastname: Andrade
authors.forename: S L
authors.initials: SL
authors.lastname: Ladeira
authors.forename: C N
authors.initials: CN
authors.lastname: Battlehner
authors.forename: P H N
authors.initials: PH
authors.lastname: Saldiva
authors.forename: E G
authors.initials: EG
authors.lastname: Caldini
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D003238:Connective Tissue / Q000648:ultrastructure*; D005355:Fibrosis / Q000473:pathology / Q000662:veterinary*; D005786:Gene Expression Regulation; D031121:Mannheimia; D009198:Myiasis / Q000150:complications; D015434:Panniculitis / Q000473:pathology / Q000662:veterinary*; D016871:Pasteurellaceae Infections / Q000150:complications / Q000473:pathology / Q000662:veterinary
chemical_list: D024042:Collagen Type I