Killer cells of feline leukemia virus- and feline sarcoma virus-infected transformed cells: the role of NK, ADCC, and in vitro generated cytotoxic cells.
Feline white blood cells (WBC) manifested a primary in vitro mixed lymphocyte tumor cell culture (MLTC) proliferative response to feline leukemia virus-feline sarcoma virus (FeLV-FeSV)-infected transformed target cells, which reached a peak at Day 15. Furthermore, primary in vitro MLTC cultures generated cytotoxic killer cells capable of killing a variety of targets in non-major histocompatibility gene complex restricted fashion, and effector cells were capable of killing targets introduced repeatedly into cultures over a 49-day period. The presence of feline fibrosarcoma (f-sarc) stimulators was the primary driving force for proliferation and generation of killing because exogenous IL-2 conditioned medium did not appreciably increase the yield of killer cells generated in vitro. WBC cultured without f-sarc stimulators with or without IL-2 supplementation also generated killer (K) cells but at a low level. The killer cell population was composed of approximately 50% lymphocytes and 50% monocytes. Cats had K cells functional in antibody-dependent cell-mediated cytotoxicity against FeLV-coated chicken red blood cells but not against any FeLV-FeSV-infected transformed targets tested. Natural killer (NK) cell activity to any targets tested was not found. Although no evidence was found for K or NK cell activity against FeLV-FeSV-infected transformed cells, feline WBC were readily able to generate killer cells in vitro and it is probable that this cell-mediated immune potential is functionally important in vivo.
Kooistra
L H
LH
Splitter
G A
GA
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity; D002415:Cats; D002417:Cattle; D002460:Cell Line; D002472:Cell Transformation, Viral; D003168:Complement Fixation Tests; D005455:Fluorescent Antibody Technique; D007694:Killer Cells, Natural / Q000276:immunology*; D005256:Leukemia Virus, Feline / Q000276:immunology; D007942:Leukemia, Experimental / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D005253:Sarcoma Viruses, Feline / Q000276:immunology; D012756:Sheep; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014412:Tumor Virus Infections / Q000276:immunology*