title: Recruitment of hepatic NK cells by IL-12 is dependent on IFN-gamma and VCAM-1 and is rapidly down-regulated by a mechanism involving T cells and expression of Fas.
abstract: NK cells have been shown to be important antitumor or antiviral effector cells in the liver. In the present study we have examined the factors that regulate the initial recruitment and subsequent fate of hepatic NK and T cells in mice treated with IL-12 or IL-2. Daily administration of IL-12 caused a rapid initial increase in NK cells followed by a subsequent decrease that coincided with an accumulation of T cells. The recruitment of hepatic NK cells by IL-12, but not the subsequent T cell infiltrate, was abrogated in IFN-gamma(-/-) mice. In contrast, daily administration of IL-2 caused a sustained increase in liver-associated NK cells that was not diminished in IFN-gamma(-/-) mice. The IL-12-induced recruitment in both hepatic NK and T cells was abrogated by in vivo treatment with anti-VCAM-1 mAbs, while treatment with anti-ICAM-1 Abs decreased only the recruitment of T cells in the IL-12-treated mice. The rapid loss of newly recruited hepatic NK cells in IL-12-treated mice did not occur in SCID mice or in B.MRL-Fas(lpr) (Fas-) and B6Smn.C3H-Fasl(gld) (FasL-) mutant mice, suggesting that T cells can actively eliminate hepatic NK cells through a Fas-dependent mechanism. These findings also imply that during the endogenous innate immune response to infectious agents or tumors or in the host response induced by cytokine therapies, the biologic effects of NK cells may be limited by T cell-mediated effects.
authors.affiliation: Laboratory of Experimental Immunology, Division of Basic Sciences, National Cancer Institute-Frederick Cancer Research and Development Center, MD 21702, USA.
authors.forename: W E
authors.initials: WE
authors.lastname: Fogler
authors.forename: K
authors.initials: K
authors.lastname: Volker
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: J M
authors.initials: JM
authors.lastname: Wigginton
authors.forename: P
authors.initials: P
authors.lastname: Roessler
authors.forename: M J
authors.initials: MJ
authors.lastname: Brunda
authors.forename: J R
authors.initials: JR
authors.lastname: Ortaldo
authors.forename: R H
authors.initials: RH
authors.lastname: Wiltrout
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D015536:Down-Regulation / Q000276:immunology; D053222:Fas Ligand Protein; D039041:Integrin alpha4beta1; D016023:Integrins / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D007371:Interferon-gamma / Q000502:physiology*; D018664:Interleukin-12 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000276:immunology* / Q000502:physiology; D008024:Ligands; D008099:Liver / Q000166:cytology / Q000276:immunology* / Q000502:physiology; D008213:Lymphocyte Activation / Q000276:immunology; D018655:Lymphocyte Count; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016513:Mice, SCID; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000502:physiology; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D019014:fas Receptor / Q000096:biosynthesis* / Q000378:metabolism / Q000502:physiology
chemical_list: D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D039041:Integrin alpha4beta1; D016023:Integrins; D007376:Interleukin-2; D008024:Ligands; D008562:Membrane Glycoproteins; D016201:Receptors, Lymphocyte Homing; D019010:Vascular Cell Adhesion Molecule-1; D019014:fas Receptor; D018799:Intercellular Adhesion Molecule-1; D018664:Interleukin-12; D007371:Interferon-gamma