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. 2005 Jan;79(1):661-7.
doi: 10.1128/JVI.79.1.661-667.2005.

Natural killer cells utilize both perforin and gamma interferon to regulate murine cytomegalovirus infection in the spleen and liver

Joy Loh  1 , Dortha T Chu, Andrew K O'Guin, Wayne M Yokoyama, Herbert W Virgin 4th
Affiliations

Natural killer cells utilize both perforin and gamma interferon to regulate murine cytomegalovirus infection in the spleen and liver

Joy Loh et al. J Virol. 2005 Jan.

Abstract

Natural killer (NK) cells are critical for innate regulation of the acute phase of murine cytomegalovirus (MCMV) infection and have been reported to utilize perforin (Pfp)- and gamma interferon (IFN-gamma)-dependent effector mechanisms in an organ-specific manner to regulate MCMV infection in the spleen and liver. In this study, we further examined the roles of NK cells, Pfp, and IFN-gamma in innate immunity to MCMV infection. With the recently described NK cell-deficient (NKD) mouse, we confirmed previous findings that NK cells, but not NKT cells, are required for control of the acute phase of MCMV infection in spleen and liver cells. Interestingly, we found that Pfp and IFN-gamma are each important for regulating MCMV replication in both the spleen and the liver. Moreover, NK cells can regulate MCMV infection in the spleens and livers of Pfp(-/-) mice in a Pfp-independent manner and can use an IFN-gamma-independent mechanism to control MCMV infection in IFN-gamma(-/-) mice. Thus, contrary to previous reports, NK cells utilize both Pfp and IFN-gamma to control MCMV infection in the spleen and liver.

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Figures

FIG. 1.
FIG. 1.
Increased susceptibility of NKD mice to MCMV infection. NKD mice were generated as previously described (25) and maintained in a specific-pathogen-free facility at the Washington University School of Medicine in accordance with all federal and university policies. B6 mice were purchased from Jackson Laboratories. The MCMV Smith strain was obtained from the American Type Culture Collection (VR-194, lot 10), and salivary gland-passaged virus stocks were generated and their titers were determined as previously described (24, 40). For all experiments, age- and sex-matched mice were infected intraperitoneally in Dulbecco modified Eagle medium containing 10% fetal calf serum. All of the data shown represent a minimum of two independent experiments. As no significant differences were observed between independent experiments, all of the data were pooled. (A) Mice infected with 105 PFU of MCMV were monitored for survival for 21 dpi. The number of mice analyzed and the P values are indicated. (B) Mice were infected with various doses of MCMV, and organs were harvested at 3 dpi and virus titers were determined by plaque assay as previously described (24). (C) Mice were infected with 5 × 104 PFU of MCMV, and organs were harvested for titer determination on various days postinfection. The number of mice analyzed is given above each bar, the limit of detection is denoted by the horizontal line, and statistically significant differences compared to B6 mice are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001).
FIG. 2.
FIG. 2.
Regulation of the early acute phase of MCMV infection does not require T, B, or NKT cells. CD1−/− mice were a kind gift from Albert Bendelac, and Rag1−/− mice were purchased from Jackson Laboratories. Mice were infected with 5 × 104 PFU of MCMV, and organs were harvested for titer determination at 3 dpi as described in the legend to Fig. 1. The number of mice analyzed is given above each bar, the limit of detection is denoted by the horizontal line, and statistically significant differences are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001).
FIG. 3.
FIG. 3.
Pfp and IFN-γ are important for protection against lethal MCMV infection. Pfp−/− and IFN-γ−/− mice were purchased from Jackson Laboratories. (A) Pfp−/− mice were infected with various doses of MCMV and monitored for survival as described in the legend to Fig. 1. Previously published data obtained with IFN-γ−/− and B6 mice are shown for comparison (41), and the 50% lethal dose is indicated by dotted lines. Mice were infected with 1 × 104 (B) or 7.5 × 104 (C) PFU of MCMV, and organs were harvested for titer determination at 3 or 6 dpi as described in the legend to Fig. 1. The number of mice analyzed is given above each bar, the limit of detection is denoted by the horizontal line, and statistically significant differences compared to B6 mice are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001).
FIG. 4.
FIG. 4.
IFN-γ has a function in regulating MCMV infection that is independent of Pfp. For IFN-γ depletion studies, mice were injected with an endotoxin-free neutralizing antibody to IFN-γ diluted in saline (H22) (46) as previously described (24). Control mice were injected with either saline alone or an isotype-matched control antibody. As no significant differences were observed between mice given saline or the control antibody, the data from these two groups were pooled. At 2 days postinjection, mice were infected with 5 × 103 PFU of MCMV and the viral titers of their spleens (A) and livers (B) were determined at 3 and 6 dpi as described in the legend to Fig. 1. The number of mice analyzed is given above each bar, the limit of detection is denoted by the horizontal line, and statistically significant differences compared to control are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001).
FIG. 5.
FIG. 5.
NK cells utilize more than one effector mechanism to control MCMV infection in the spleen and liver. For NK cell depletion, mice were intraperitoneally injected with either 300 μg of antibody to NK1.1 (PK136; ATCC HB-191) or an isotype-matched control antibody (MAR 18.5; ATCC TIB-216). Depletion of NK cells was confirmed by 51Cr release assay as previously described (25). At 2 days postinjection, mice were infected with 5 × 103 PFU of MCMV and the viral titers of Pfp−/− (A) and IFN-γ−/− (B) mice were determined at 3 dpi as described in the legend to Fig. 1. The number of mice analyzed is given above each bar, the limit of detection is denoted by the horizontal line, and statistically significant differences compared to control are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001).
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References

    1. Anderson, K. P., Y. S. Lie, M. A. Low, and E. H. Fennie. 1993. Effects of tumor necrosis factor-alpha treatment on mortality in murine cytomegalovirus-infected mice. Antiviral Res. 21:343-355. - PubMed
    1. Arase, H., E. S. Mocarski, A. E. Campbell, A. B. Hill, and L. L. Lanier. 2002. Direct recognition of cytomegalovirus by activating and inhibitory NK cell receptors. Science 296:1323-1326. - PubMed
    1. Baetz, K., S. Isaaz, and G. M. Griffiths. 1995. Loss of cytotoxic T lymphocyte function in Chediak-Higashi syndrome arises from a secretory defect that prevents lytic granule exocytosis. J. Immunol. 154:6122-6131. - PubMed
    1. Bancroft, G. J., G. R. Shellam, and J. E. Chalmer. 1981. Genetic influences on the augmentation of natural killer (NK) cells during murine cytomegalovirus infection: correlation with patterns of resistance. J. Immunol. 126:988-994. - PubMed
    1. Barbosa, M. D., Q. A. Nguyen, V. T. Tchernev, J. A. Ashley, J. C. Detter, S. M. Blaydes, S. J. Brandt, D. Chotai, C. Hodgman, R. C. Solari, M. Lovett, and S. F. Kingsmore. 1996. Identification of the homologous beige and Chediak-Higashi syndrome genes. Nature 382:262-265. - PMC - PubMed

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