title: Stimulation of a cell-mediated cytotoxic response to FeLV-induced T cell lymphomas in the cat.
abstract: Nonspecific cell-mediated cytotoxicity was examined in the peripheral blood and spleens of normal and vaccinia virus-infected adult domestic cats. Natural cytotoxic (NC)-like cells, as measured by lysis of vaccinia- or HSV-infected, adherent cat tongue cells, were found in both the spleen and peripheral blood of normal, nonimmune cats. Cytotoxicity was expressed in a 16-hr assay but not in a 4-hr assay. Natural killer (NK)-like cells, as measured by lysis of an FeLV-induced lymphoid tumor cell line (FL-74) growing in suspension, were found in the spleen but not PBL, and required a 16-hr assay for expression. Infection with vaccinia virus did not increase the activity of feline NC-like cells in either the peripheral blood or the spleen. NK-like function, however, was increased. Cytotoxicity peaked 6 days post-infection and required a 16-hr assay for maximal expression of cell lysis. Furthermore, a cell with cytotoxic characteristics of the spleen NK-like cell appeared at low levels in the circulation at 6 days post-vaccinia infection. NK-like cells from vaccinia-infected cats showed some cytotoxicity for FL74 targets in a 4-hr assay. The cat thus possesses at least two functionally different populations of naturally cytotoxic cells. NC-like cells are found in the spleen and peripheral blood, lyse virus-infected monolayer targets, and are not activated by infection. NK-like cells are found in the spleen, lyse-lymphoid tumor targets, and can be activated by infection, with their peak activity occurring 6 days after infection.
authors.forename: M B
authors.initials: MB
authors.lastname: Tompkins
authors.forename: W A
authors.initials: WA
authors.lastname: Tompkins
mesh_terms: D000818:Animals; D002415:Cats; D002448:Cell Adhesion; D002460:Cell Line; D002472:Cell Transformation, Viral; D003601:Cytotoxicity Tests, Immunologic / Q000379:methods; D003602:Cytotoxicity, Immunologic; D005260:Female; D007694:Killer Cells, Natural / Q000276:immunology*; D005256:Leukemia Virus, Feline / Q000276:immunology*; D008223:Lymphoma / Q000276:immunology*; D008297:Male; D013154:Spleen / Q000166:cytology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013997:Time Factors; D014615:Vaccinia / Q000276:immunology