title: Local pulmonary immune responses in domestic cats naturally infected with Cytauxzoon felis.
abstract: Cytauxzoonosis is a hemoprotozoal disease of cats and wild felids in the South and Southeastern United States caused by Cytauxzoon felis. Although the causative agent has been recognized since the seventies, no study has examined the local immune response in affected organs, such as the lung, and compared them to the lungs of uninfected domestic cats. Previous studies have suggested that the histopathologic findings in the lungs of C. felis-infected cats are caused by the release of pro-inflammatory mediators, such as cytokines and increased production of inducible nitric oxide synthase (iNOS), by the infected macrophages. Our laboratory had previously found an upregulation of the adhesion molecule CD18, which can stimulate the release of these pro-inflammatory mediators. The objective of this study was to characterize local pulmonary immune responses in cats naturally infected with C. felis. Immunohistochemistry was performed to detect tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, iNOS, and major histocompatibility complex (MHC) II in 19 lungs from affected cats that died between 2005 and 2013. Results showed increased expression of all of these molecules when compared to lungs from uninfected, healthy cats. Furthermore, MHC II is expressed in the endothelium of C. felis naturally infected cats. These results support that there is a marked, local, pro-inflammatory immune response that can contribute to the pathogenesis of cytauxzoonosis in the lungs.
authors.affiliation: School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, Building 47, Eric Williams Medical Sciences Complex, Uriah Butler Highway, Champ Fleurs, Trinidad and Tobago.
authors.forename: Karelma
authors.initials: K
authors.lastname: Frontera-Acevedo
authors.affiliation: Department of Pathology, The University of Georgia, College of Veterinary Medicine, 501 D.W. Brooks Dr., Athens, GA 30602, United States. Electronic address: kaoris@uga.edu.
authors.forename: Kaori
authors.initials: K
authors.lastname: Sakamoto
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000276:immunology / Q000469:parasitology* / Q000473:pathology; D002415:Cats; D005802:Genes, MHC Class II / Q000502:physiology; D053583:Interleukin-1beta / Q000032:analysis; D008168:Lung / Q000737:chemistry / Q000276:immunology* / Q000473:pathology; D052247:Nitric Oxide Synthase Type II / Q000032:analysis; D016794:Theileria / Q000276:immunology* / Q000469:parasitology; D013801:Theileriasis / Q000276:immunology* / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D052247:Nitric Oxide Synthase Type II
keywords: Cat; Cytauxzoon felis; Immune response; Lung; Macrophage; Pathology