title: CD8(+)/perforin(+)/WC1(-) gammadelta T cells, not CD8(+) alphabeta T cells, infiltrate vasculitis lesions of American bison (Bison bison) with experimental sheep-associated malignant catarrhal fever.
abstract: Sheep-associated malignant catarrhal fever (SA-MCF) caused by ovine herpesvirus-2 (OvHV-2), a gamma-herpesvirus in the Macavirus genus, is a fatal disease associated with lymphoproliferation, lymphocytic vasculitis, and mucosal ulceration in clinically susceptible species. SA-MCF is an important threat to American bison (Bison bison) due to their high susceptibility to this disease. Currently, the pathogenesis of disease in SA-MCF is poorly understood, and the immunophenotype of lymphocytes that infiltrate the vascular lesions of bison and cattle with SA-MCF has been only partially defined. Previous single-color immunohistochemistry studies have demonstrated that CD8(+) cells and CD4(+) cells predominate within vascular infiltrates in cattle and bison. The CD8(+) cells detected in the vascular lesions of cattle and bison were assumed to be cytotoxic alphabeta T lymphocytes. However, polychromatic immunophenotyping analyses in this study showed that CD8(+)/perforin(+) gammadelta T cells, CD4(+)/perforin(-) alphabeta T cells, and B cells infiltrate vascular lesions in the urinary bladder, kidney, and liver of six bison with experimentally-induced SA-MCF. CD8(+) alphabeta T cells and WC1(+) gammadelta T cell cells were only infrequently and inconsistently identified. This study confirmed our hypothesis that the predominant CD8(+) lymphocytes infiltrating the vascular lesions of bison with SA-MCF are cytotoxic lymphocytes of the innate immune system, not CD8(+) alphabeta T cells. Results of the present study support the previous suggestions that MCF is fundamentally a disease of immune dysregulation.
authors.affiliation: Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA. danielled@vetmed.wsu.edu
authors.forename: Danielle D
authors.initials: DD
authors.lastname: Nelson
authors.forename: William C
authors.initials: WC
authors.lastname: Davis
authors.forename: Wendy C
authors.initials: WC
authors.lastname: Brown
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Donal
authors.initials: D
authors.lastname: O'Toole
authors.forename: J Lindsay
authors.initials: JL
authors.lastname: Oaks
mesh_terms: D000818:Animals; D016164:Bison / Q000276:immunology / Q000821:virology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D018142:Gammaherpesvirinae / Q000276:immunology*; D006566:Herpesviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D016130:Immunophenotyping / Q000379:methods / Q000662:veterinary*; D008297:Male; D008304:Malignant Catarrh / Q000276:immunology / Q000821:virology*; D008856:Microscopy, Fluorescence; D054353:Perforin / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014657:Vasculitis / Q000276:immunology / Q000662:veterinary* / Q000821:virology
chemical_list: D016692:Receptors, Antigen, T-Cell, gamma-delta; D054353:Perforin