title: IFN-gamma promotes Fas ligand- and perforin-mediated liver cell destruction by cytotoxic CD8 T cells.
abstract: To study liver cell damage by CTL, CD8 T cells from P14 TCR transgenic (tg) mice specific for the gp33 epitope of lymphocytic choriomeningitis virus with either deficiency in IFN-gamma (P14.IFN-gamma(null)), functional Fas ligand (P14.gld), or perforin (P14.PKO) were transferred into H8 tg mice ubiquitously expressing gp33 Ag. Treatment of H8 recipient mice with agonistic anti-CD40 Abs induced vigorous expansion of the transferred P14 T cells and led to liver cell destruction determined by increase of glutamate dehydrogenase serum levels and induction of caspase-3 in hepatocytes. Liver injury was mediated by the Fas/Fas ligand (FasL) pathway and by perforin, because P14.gld and P14.PKO T cells failed to induce increased glutamate dehydrogenase levels despite strong in vivo proliferation. In addition, H8 tg mice lacking Fas were resistant to the pathogenic effect of P14 T cells. Besides FasL and perforin, IFN-gamma was also required for liver cell damage, because P14.IFN-gamma(null) T cells adoptively transferred into H8 mice failed to induce disease. Moreover, Fas expression on hepatocytes from H8 recipient mice was increased after transfer of wild-type compared with P14.IFN-gamma(null) T cells, and wild-type P14 T cells expressed higher levels of FasL than P14 T cells lacking IFN-gamma. Thus, our data suggest that IFN-gamma released by activated CD8 T cells upon Ag contact facilitates liver cell destruction.
authors.affiliation: Institute for Medical Microbiology and Hygiene, Department of Immunology, University of Freiburg, Freiburg, Germany.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Roth
authors.forename: Hanspeter
authors.initials: H
authors.lastname: Pircher
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D003602:Cytotoxicity, Immunologic / Q000235:genetics; D053222:Fas Ligand Protein; D005260:Female; D006520:Hepatitis, Animal / Q000235:genetics / Q000276:immunology* / Q000473:pathology*; D022781:Hepatocytes / Q000276:immunology / Q000378:metabolism; D007371:Interferon-gamma / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008024:Ligands; D008213:Lymphocyte Activation / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D013154:Spleen / Q000276:immunology / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation; D015854:Up-Regulation / Q000235:genetics / Q000276:immunology; D019014:fas Receptor / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008024:Ligands; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D019014:fas Receptor; D054353:Perforin; D007371:Interferon-gamma