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• W2072158757 abstract "•Ifnar1−/− T cells show abortive expansion following LCMV infection•Activated Ifnar1−/− T cells are killed in a perforin-dependent manner by NK cells•Activated Ifnar1−/−, but not WT T cells, upregulate ligands for NCR1•NK cells kill activated Ifnar1−/− T cells via NCR1 engagement Direct type I interferon (IFN) signaling on T cells is necessary for the proper expansion, differentiation, and survival of responding T cells following infection with viruses prominently inducing type I IFN. The reasons for the abortive response of T cells lacking the type I IFN receptor (Ifnar1−/−) remain unclear. We report here that Ifnar1−/− T cells were highly susceptible to natural killer (NK) cell-mediated killing in a perforin-dependent manner. Depletion of NK cells prior to lymphocytic choriomeningitis virus (LCMV) infection completely restored the early expansion of Ifnar1−/− T cells. Ifnar1−/− T cells had elevated expression of natural cytotoxicity triggering receptor 1 (NCR1) ligands upon infection, rendering them targets for NCR1 mediated NK cell attack. Thus, direct sensing of type I IFNs by T cells protects them from NK cell killing by regulating the expression of NCR1 ligands, thereby revealing a mechanism by which T cells can evade the potent cytotoxic activity of NK cells. Direct type I interferon (IFN) signaling on T cells is necessary for the proper expansion, differentiation, and survival of responding T cells following infection with viruses prominently inducing type I IFN. The reasons for the abortive response of T cells lacking the type I IFN receptor (Ifnar1−/−) remain unclear. We report here that Ifnar1−/− T cells were highly susceptible to natural killer (NK) cell-mediated killing in a perforin-dependent manner. Depletion of NK cells prior to lymphocytic choriomeningitis virus (LCMV) infection completely restored the early expansion of Ifnar1−/− T cells. Ifnar1−/− T cells had elevated expression of natural cytotoxicity triggering receptor 1 (NCR1) ligands upon infection, rendering them targets for NCR1 mediated NK cell attack. Thus, direct sensing of type I IFNs by T cells protects them from NK cell killing by regulating the expression of NCR1 ligands, thereby revealing a mechanism by which T cells can evade the potent cytotoxic activity of NK cells. Proper activation, expansion, and differentiation of T cells is critical for the clearance of viral infections and is dependent on three key signals: antigen presentation, costimulation, and cytokine signaling. The nature of the infecting pathogen determines which cytokines serve as signal 3 cytokines, with the two most studied being interleukin-12 (IL-12) and type I interferons (IFNs) (Aichele et al., 2006Aichele P. Unsoeld H. Koschella M. Schweier O. Kalinke U. Vucikuja S. CD8 T cells specific for lymphocytic choriomeningitis virus require type I IFN receptor for clonal expansion.J. Immunol. 2006; 176: 4525-4529Crossref PubMed Scopus (136) Google Scholar, Keppler et al., 2009Keppler S.J. Theil K. Vucikuja S. Aichele P. Effector T-cell differentiation during viral and bacterial infections: Role of direct IL-12 signals for cell fate decision of CD8(+) T cells.Eur. J. Immunol. 2009; 39: 1774-1783Crossref PubMed Scopus (45) Google Scholar, Kolumam et al., 2005Kolumam G.A. Thomas S. Thompson L.J. Sprent J. Murali-Krishna K. Type I interferons act directly on CD8 T cells to allow clonal expansion and memory formation in response to viral infection.J. Exp. Med. 2005; 202: 637-650Crossref PubMed Scopus (717) Google Scholar). T cell responses are dependent on type I IFNs during lymphocytic choriomeningitis virus (LCMV) infection, where the inability to directly sense type I IFNs leads to curtailed expansion (Aichele et al., 2006Aichele P. Unsoeld H. Koschella M. Schweier O. Kalinke U. Vucikuja S. CD8 T cells specific for lymphocytic choriomeningitis virus require type I IFN receptor for clonal expansion.J. Immunol. 2006; 176: 4525-4529Crossref PubMed Scopus (136) Google Scholar, Kolumam et al., 2005Kolumam G.A. Thomas S. Thompson L.J. Sprent J. Murali-Krishna K. Type I interferons act directly on CD8 T cells to allow clonal expansion and memory formation in response to viral infection.J. Exp. Med. 2005; 202: 637-650Crossref PubMed Scopus (717) Google Scholar) and altered differentiation of antiviral T cells (Wiesel et al., 2012Wiesel M. Crouse J. Bedenikovic G. Sutherland A. Joller N. Oxenius A. Type-I IFN drives the differentiation of short-lived effector CD8+ T cells in vivo.Eur. J. Immunol. 2012; 42: 320-329Crossref PubMed Scopus (60) Google Scholar). The cause(s) for the abortive expansion of T cells lacking the type I IFN receptor (Ifnar1−/−) are unknown and their identification is critical to understand the regulation of T cell dynamics during acute viral infections. In addition to their role as signal 3 cytokines for T cell activation, type I IFNs act on numerous cell types leading to the establishment of an antiviral state (Stark et al., 1998Stark G.R. Kerr I.M. Williams B.R. Silverman R.H. Schreiber R.D. How cells respond to interferons.Annu. Rev. Biochem. 1998; 67: 227-264Crossref PubMed Scopus (3375) Google Scholar). Natural killer (NK) cells can be activated directly by type I IFNs (Biron et al., 1984Biron C.A. Sonnenfeld G. Welsh R.M. Interferon induces natural killer cell blastogenesis in vivo.J. Leukoc. Biol. 1984; 35: 31-37PubMed Google Scholar, Gidlund et al., 1978Gidlund M. Orn A. Wigzell H. Senik A. Gresser I. Enhanced NK cell activity in mice injected with interferon and interferon inducers.Nature. 1978; 273: 759-761Crossref PubMed Scopus (533) Google Scholar). NK cells play a central role in the innate immune response and contribute to the clearance of certain viral infections and cancerous cells (French and Yokoyama, 2003French A.R. Yokoyama W.M. Natural killer cells and viral infections.Curr. Opin. Immunol. 2003; 15: 45-51Crossref PubMed Scopus (231) Google Scholar, Wu and Lanier, 2003Wu J. Lanier L.L. Natural killer cells and cancer.Adv. Cancer Res. 2003; 90: 127-156Crossref PubMed Scopus (330) Google Scholar), either via direct cytotoxic functions, via provision of inflammatory cytokines such as IFN-γ, or via crosstalk to antigen-presenting cells (APCs) and subsequent regulation of T cells (Cook and Whitmire, 2013Cook K.D. Whitmire J.K. The depletion of NK cells prevents T cell exhaustion to efficiently control disseminating virus infection.J. Immunol. 2013; 190: 641-649Crossref PubMed Scopus (97) Google Scholar). NK cells recognize target cells through an array of activating and inhibitory receptors (Cerwenka and Lanier, 2001Cerwenka A. Lanier L.L. Ligands for natural killer cell receptors: redundancy or specificity.Immunol. Rev. 2001; 181: 158-169Crossref PubMed Scopus (225) Google Scholar). When signals from activating ligands outweigh those of inhibitory signals, NK cell effector functions are triggered. Inhibitory ligands, such as major histocompatibility complex (MHC) class I, are important for maintaining NK cell self-tolerance and preventing autoimmunity (Yokoyama, 1995Yokoyama W.M. Natural killer cell receptors specific for major histocompatibility complex class I molecules.Proc. Natl. Acad. Sci. USA. 1995; 92: 3081-3085Crossref PubMed Scopus (98) Google Scholar), whereas activating ligands, such as the mouse cytomegalovirus (MCMV) viral protein m157 recognized by Ly49H on NK cells are important for protection against viral infection (Arase et al., 2002Arase H. Mocarski E.S. Campbell A.E. Hill A.B. Lanier L.L. Direct recognition of cytomegalovirus by activating and inhibitory NK cell receptors.Science. 2002; 296: 1323-1326Crossref PubMed Scopus (970) Google Scholar). In addition to their direct role in viral clearance and control of “altered” self cells, NK cells can regulate T cell responses in a positive and negative manner. Such regulation can occur in an indirect manner, for instance via the elimination of antigen-presenting dendritic cells, having a negative impact on the induction of T cell responses and the success of vaccination (Andrews et al., 2010Andrews D.M. Estcourt M.J. Andoniou C.E. Wikstrom M.E. Khong A. Voigt V. Fleming P. Tabarias H. Hill G.R. van der Most R.G. et al.Innate immunity defines the capacity of antiviral T cells to limit persistent infection.J. Exp. Med. 2010; 207: 1333-1343Crossref PubMed Scopus (170) Google Scholar, Hayakawa et al., 2004Hayakawa Y. Screpanti V. Yagita H. Grandien A. Ljunggren H.G. Smyth M.J. Chambers B.J. NK cell TRAIL eliminates immature dendritic cells in vivo and limits dendritic cell vaccination efficacy.J. Immunol. 2004; 172: 123-129Crossref PubMed Scopus (180) Google Scholar). In a direct manner, NK cells were shown to regulate T cell responses through cytokine secretion or direct cytolysis, whereby NK cells can directly kill CD8+ and CD4+ T cells (Lang et al., 2012Lang P.A. Lang K.S. Xu H.C. Grusdat M. Parish I.A. Recher M. Elford A.R. Dhanji S. Shaabani N. Tran C.W. et al.Natural killer cell activation enhances immune pathology and promotes chronic infection by limiting CD8+ T-cell immunity.Proc. Natl. Acad. Sci. USA. 2012; 109: 1210-1215Crossref PubMed Scopus (240) Google Scholar, Lu et al., 2007Lu L. Ikizawa K. Hu D. Werneck M.B. Wucherpfennig K.W. Cantor H. Regulation of activated CD4+ T cells by NK cells via the Qa-1-NKG2A inhibitory pathway.Immunity. 2007; 26: 593-604Abstract Full Text Full Text PDF PubMed Scopus (194) Google Scholar, Soderquest et al., 2011Soderquest K. Walzer T. Zafirova B. Klavinskis L.S. Polić B. Vivier E. Lord G.M. Martín-Fontecha A. Cutting edge: CD8+ T cell priming in the absence of NK cells leads to enhanced memory responses.J. Immunol. 2011; 186: 3304-3308Crossref PubMed Scopus (104) Google Scholar, Waggoner et al., 2010Waggoner S.N. Taniguchi R.T. Mathew P.A. Kumar V. Welsh R.M. Absence of mouse 2B4 promotes NK cell-mediated killing of activated CD8+ T cells, leading to prolonged viral persistence and altered pathogenesis.J. Clin. Invest. 2010; 120: 1925-1938Crossref PubMed Scopus (104) Google Scholar, Waggoner et al., 2012Waggoner S.N. Cornberg M. Selin L.K. Welsh R.M. Natural killer cells act as rheostats modulating antiviral T cells.Nature. 2012; 481: 394-398Google Scholar, Waggoner et al., 2014Waggoner S.N. Daniels K.A. Welsh R.M. Therapeutic depletion of natural killer cells controls persistent infection.J. Virol. 2014; 88: 1953-1960Crossref PubMed Scopus (55) Google Scholar), thereby affecting the size of the antigen-specific T cell pool and the control of an infection. Multiple NK cell ligands are proposed to play a role in this killing process; blockade of the activating receptor NKG2D leads to enhanced CD8+ T cell responses in the context of peptide vaccination (Soderquest et al., 2011Soderquest K. Walzer T. Zafirova B. Klavinskis L.S. Polić B. Vivier E. Lord G.M. Martín-Fontecha A. Cutting edge: CD8+ T cell priming in the absence of NK cells leads to enhanced memory responses.J. Immunol. 2011; 186: 3304-3308Crossref PubMed Scopus (104) Google Scholar) and high dose LCMV infection (Lang et al., 2012Lang P.A. Lang K.S. Xu H.C. Grusdat M. Parish I.A. Recher M. Elford A.R. Dhanji S. Shaabani N. Tran C.W. et al.Natural killer cell activation enhances immune pathology and promotes chronic infection by limiting CD8+ T-cell immunity.Proc. Natl. Acad. Sci. USA. 2012; 109: 1210-1215Crossref PubMed Scopus (240) Google Scholar), whereas expression of the inhibitory ligands Qa1 and CD48 on T cells can confer protection against NK cell mediated lysis (Lu et al., 2007Lu L. Ikizawa K. Hu D. Werneck M.B. Wucherpfennig K.W. Cantor H. Regulation of activated CD4+ T cells by NK cells via the Qa-1-NKG2A inhibitory pathway.Immunity. 2007; 26: 593-604Abstract Full Text Full Text PDF PubMed Scopus (194) Google Scholar, Waggoner et al., 2010Waggoner S.N. Taniguchi R.T. Mathew P.A. Kumar V. Welsh R.M. Absence of mouse 2B4 promotes NK cell-mediated killing of activated CD8+ T cells, leading to prolonged viral persistence and altered pathogenesis.J. Clin. Invest. 2010; 120: 1925-1938Crossref PubMed Scopus (104) Google Scholar). What remains to be explained is whether and how T cells can protect themselves from NK-cell-mediated killing. In this study we sought to address these questions by identifying the mechanisms responsible for the impaired expansion of Ifnar1−/− LCMV-specific CD8+ and CD4+ T cells during acute LCMV infection. By performing a whole-genome gene-expression analysis, we found many molecules involved in cell death being differentially regulated in Ifnar1−/− LCMV-specific CD8+ T cells compared to their WT counterparts, among which were multiple NK cell activating and inhibitory ligands. In vivo depletion of NK cells revealed a key role for NK cells in the negative regulation of Ifnar1−/− T cells, with NK cell depletion during priming leading to a complete recovery of the early Ifnar1−/− T cell expansion. We further found that NK cells selectively killed activated Ifnar1−/− T cells in a perforin-dependent manner via engagement of natural cytotoxicity triggering receptor 1 (NCR1) ligands being specifically upregulated on Ifnar1−/− T cells. Our data establish a mechanism whereby type I IFN signaling on activated T cells is pivotal to protect them from NCR1-mediated NK cell attack. To investigate the reason(s) for the compromised expansion of CD8+ T cells lacking the ability to sense type I IFN during LCMV infection, we performed a whole-genome microarray comparing type I IFN receptor sufficient (WT) and deficient (Ifnar1−/−) LCMV-specific CD8+ T cells. WT and Ifnar1−/− T cell receptor (TCR) transgenic CD8+ T cells specific for the LCMV glycoprotein gp33–41 (P14) were cotransferred into naive C57BL/6 (Bl6) mice followed by LCMV infection. To increase the low Ifnar1−/− P14 T cell numbers recovered following LCMV infection, we utilized the previously described LCMV8.7 and vaccinia virus (VVG2) coinfection (Wiesel et al., 2011Wiesel M. Kratky W. Oxenius A. Type I IFN substitutes for T cell help during viral infections.J. Immunol. 2011; 186: 754-763Crossref PubMed Scopus (50) Google Scholar), where the inflammatory environment is provided by the LCMV8.7 mutant, which is not recognized by P14 cells, and antigen is provided by the LCMV-GP recombinant VVG2. This setup leads to greater expansion of both Ifnar1−/− and WT P14 T cells compared to LCMV, allowing for analysis of Ifnar1−/− P14 cells at early time points. Importantly, the ratio between Ifnar1−/− and WT cells is comparable in the coinfection and single infection models (Figures 1A and 1B ) and it has been previously shown that there is no difference in the phenotype or differentiation of P14 cells in the two infection models (Wiesel et al., 2012Wiesel M. Crouse J. Bedenikovic G. Sutherland A. Joller N. Oxenius A. Type-I IFN drives the differentiation of short-lived effector CD8+ T cells in vivo.Eur. J. Immunol. 2012; 42: 320-329Crossref PubMed Scopus (60) Google Scholar). For microarray analysis, WT and Ifnar1−/− P14 cells were sorted to high purity based on expression of the congenic markers Ly5.1 (WT) and Thy1.1 (Ifnar1−/−) at day 3 post coinfection, the time point corresponding to the peak of Ifnar1−/− P14 expansion (data not shown) (Figure 1C). Analysis of genes more than 2-fold differentially regulated revealed 631 genes that were differentially expressed in activated Ifnar1−/− and WT P14 cells. Of these genes, 374 were upregulated in Ifnar1−/− compared to WT P14 cells and 257 were downregulated. Pathway analysis of the 631 genes revealed that many genes grouped together into distinct functional pathways (Figure 1D). The pathways with the greatest number of differentially expressed genes were those related to signaling and signal transduction, metabolic processes, cell death and apoptosis, and IFN signaling. Of particular interest were those genes associated with cell death regulation, as these could be of direct relevance for the abortive expansion of Ifnar1−/− P14 cells. Further analysis revealed differential expression of many genes encoding ligands for NK cell activating or inhibitory receptors (Figure 1E). In combination with recent reports demonstrating NK cell regulation of T cell responses, we decided to further examine a potential role of NK cells in the negative regulation of Ifnar1−/− P14 cell expansion. To test for a regulatory role of NK cells, we cotransferred WT and Ifnar1−/− P14 cells into NK cell depleted (aNK1.1) or undepleted (Bl6) mice followed by acute LCMV strain WE (LCMV-WE) infection. Depletion of NK cells led to the complete recovery of Ifnar1−/− P14 cell expansion at day 4 postinfection (p.i.), both in percentage and total cell numbers (Figures 2A and 2B ). This ∼20-fold increase in expansion was observed in spleen and lymph nodes (data not shown). Consistent with previous reports (Lang et al., 2012Lang P.A. Lang K.S. Xu H.C. Grusdat M. Parish I.A. Recher M. Elford A.R. Dhanji S. Shaabani N. Tran C.W. et al.Natural killer cell activation enhances immune pathology and promotes chronic infection by limiting CD8+ T-cell immunity.Proc. Natl. Acad. Sci. USA. 2012; 109: 1210-1215Crossref PubMed Scopus (240) Google Scholar, Lu et al., 2007Lu L. Ikizawa K. Hu D. Werneck M.B. Wucherpfennig K.W. Cantor H. Regulation of activated CD4+ T cells by NK cells via the Qa-1-NKG2A inhibitory pathway.Immunity. 2007; 26: 593-604Abstract Full Text Full Text PDF PubMed Scopus (194) Google Scholar, Soderquest et al., 2011Soderquest K. Walzer T. Zafirova B. Klavinskis L.S. Polić B. Vivier E. Lord G.M. Martín-Fontecha A. Cutting edge: CD8+ T cell priming in the absence of NK cells leads to enhanced memory responses.J. Immunol. 2011; 186: 3304-3308Crossref PubMed Scopus (104) Google Scholar, Waggoner et al., 2012Waggoner S.N. Cornberg M. Selin L.K. Welsh R.M. Natural killer cells act as rheostats modulating antiviral T cells.Nature. 2012; 481: 394-398Google Scholar, Waggoner et al., 2010Waggoner S.N. Taniguchi R.T. Mathew P.A. Kumar V. Welsh R.M. Absence of mouse 2B4 promotes NK cell-mediated killing of activated CD8+ T cells, leading to prolonged viral persistence and altered pathogenesis.J. Clin. Invest. 2010; 120: 1925-1938Crossref PubMed Scopus (104) Google Scholar), we observed a moderate increase (∼1.5-fold) in expansion of WT P14 cells in NK-cell-depleted mice. Furthermore, previous reports found that Ifnar1−/− CD4+ T cells also show a strong reduction in expansion following LCMV infection (Havenar-Daughton et al., 2006Havenar-Daughton C. Kolumam G.A. Murali-Krishna K. Cutting Edge: The direct action of type I IFN on CD4 T cells is critical for sustaining clonal expansion in response to a viral but not a bacterial infection.J. Immunol. 2006; 176: 3315-3319Crossref PubMed Scopus (166) Google Scholar). Therefore, we generated Ifnar1−/− Smarta (SM) cells, being transgenic CD4+ T cells specific for the LCMV glycoprotein gp61–80 epitope. Cotransfer of WT and Ifnar1−/− SM cells into NK-cell-depleted mice followed by LCMV infection revealed that Ifnar1−/− SM cell expansion could also be completely recovered to WT amounts by NK cell depletion (Figures 2A and 2B). In addition, Ifnar1−/− P14 cell expansion was also recovered with the anti-Asialo GM1 NK-cell-depleting antibody, which targets an epitope not expressed on NKT or T cells (see Figure S1 available online). Analysis of P14 cell function at day 4 p.i. revealed that NK cell depletion had no significant effect on the activation (CD44) or effector functions of WT and Ifnar1−/− P14 cells, as shown by percentage of IFN-γ, perforin, and granzyme B-positive T cells (Figure 2C). Furthermore, comparing the global gene-expression profiles of P14 cells isolated from Bl6 and NK-cell-depleted mice by cluster analysis revealed that NK cell depletion had little effect on the overall expression profile of WT or Ifnar1−/− P14 cells (Figure 2D). Next, we addressed the question of whether naive Ifnar1−/− P14 cells are also sensitive to NK-cell-mediated killing. To this end, we infected mice with LCMV8.7, following cotransfer with WT and Ifnar1−/− P14 cells. In this setting, P14 cells remain antigen inexperienced but the inflammatory environment and NK cell activation remains the same as in LCMV-WE infection. WT and Ifnar1−/− P14 cell numbers were comparable during LCMV8.7 infection with or without NK cell depletion (Figure 2E), indicating that T cells need to be activated for negative regulation by NK cells. Finally, NK cell depletion could also recover Ifnar1−/− P14 cell expansion to the level of WT P14 cells during infection with vesicular stomatitis virus expressing the LCMV glycoprotein (VSVGP), another infection associated with high amounts of type I IFNs (Figure 2F). Taken together, we found that both CD8+ and CD4+ T cells lacking the ability to sense type I IFNs are highly susceptible to negative regulation by NK cells. NK cell depletion leads to a full recovery of expansion of Ifnar1−/− P14 cells up to day 4 p.i., but at day 7 p.i., Ifnar1−/− P14 cells exhibited reduced expansion compared to WT P14 cells, which could partially be recovered by NK cell depletion (Figures 3A and 3B ). Nonetheless, NK cell depletion led to a ∼100-fold increase in total Ifnar1−/− P14 cell numbers compared to undepleted controls. Similar to Ifnar1−/− P14 cells, Ifnar1−/− SM cells also exhibited a partial recovery of expansion at day 7 p.i. when NK cells were depleted (Figures 3A and 3B). Comparable results were obtained with aNK1.1 and anti-Asialo-GM1 targeted NK cell depletion (Figure S2). To examine the effect of NK cells on the endogenous Ifnar1−/− T cell response, we utilized mice in which T cells specifically lack the type I IFN receptor (Cd4creIfnar1flox/flox) (Kamphuis et al., 2006Kamphuis E. Junt T. Waibler Z. Forster R. Kalinke U. Type I interferons directly regulate lymphocyte recirculation and cause transient blood lymphopenia.Blood. 2006; 108: 3253-3261Crossref PubMed Scopus (212) Google Scholar). We found a substantial recovery in the expansion of total activated (CD44hi) or gp33 tetramer and np396 tetramer-specific CD8+ T cells in NK-cell-depleted (aNK1.1) Cd4creIfnar1flox/flox mice compared to undepleted (Ø) mice at day 7 p.i. (Figure 3C). As previously reported, Ifnar1−/− P14 cells failed to differentiate into short-lived effector cells (SLECs) and were skewed toward a memory precursor effector cell (MPEC) phenotype. Depletion of NK cells had no effect on acquisition of this differential phenotype between WT or Ifnar1−/− P14 cells (Figure 3D). Next, we examined memory formation of WT and Ifnar1−/− P14 cells with and without NK cell depletion. Depletion of NK cells during priming led to a substantial increase in the percentage and number (Figures 3E and 3F) of Ifnar1−/− memory P14 cells compared to the undepleted situation. Phenotypically, NK cell depletion during priming had no effect on the differentiation of memory cells into central and effector memory cells at day 80 p.i. and VVG2 challenge revealed that WT and Ifnar1−/− P14 cells were equally functional with respect to recall potential and exertion of effector functions, regardless of whether they had been primed in the presence or absence of NK cells (Figure S3). Taken together, NK cell depletion leads to a partial recovery of Ifnar1−/− T cell expansion at day 7 p.i. and substantially increased formation of functional memory cells. Similar to primary T cell responses, memory recall of CD8+ T cells is also dependent on signal 3 cytokines as memory Ifnar1−/− CD8+ T cells show greatly reduced recall expansion during LCMV infection (Keppler and Aichele, 2011Keppler S.J. Aichele P. Signal 3 requirement for memory CD8+ T-cell activation is determined by the infectious pathogen.Eur. J. Immunol. 2011; 41: 3176-3186Crossref PubMed Scopus (23) Google Scholar). Therefore, we examined whether the memory response to LCMV is also negatively regulated by NK cells in the absence of type I IFN signaling on CD8+ T cells. To generate memory P14 cells, we cotransfected WT and Ifnar1−/− P14 cells into naive mice followed by VVG2 infection (Figure 4A). At day 80 p.i., WT and Ifnar1−/− P14 cells had differentiated into phenotypically equivalent memory cells (Figure 4B). At this time point, memory CD8+ T cells were purified and transferred into either NK cell depleted or undepleted mice, followed by challenge with LCMV-WE or VVG2. At day 4 postchallenge, analysis of T cell expansion in the blood revealed reduced expansion of Ifnar1−/− P14 cells during LCMV challenge, which could be completely restored by NK cell depletion during the challenge phase (Figure 4C). At day 7 post LCMV challenge, as during the primary response, NK cell depletion led to a partial recovery of Ifnar1−/− P14 cell expansion (Figure 4D). In summary, both primary and secondary CD8+ T cell responses to LCMV are dependent on type I IFN signaling, and depletion of NK cells leads to enhanced expansion of both naive and memory Ifnar1−/− P14 cells. To investigate the mechanisms of how this negative regulation occurs, we focused on a potential role of perforin-mediated cytotoxicity. To this end, we cotransferred WT and Ifnar1−/− P14 cells into perforin-deficient (Prf1−/−) mice followed by LCMV infection. Analysis at day 4 p.i. revealed that Ifnar1−/− P14 cell priming in Prf1−/− mice led to the complete recovery of early expansion (Figures 5A and 5B ). The expansion of Ifnar1−/− P14 cells in Prf1−/− mice was comparable to NK cell depletion in Bl6 mice, and NK cell depletion in Prf1−/− mice had no additional effect (Figure S4). Furthermore, at day 7 p.i., expansion of Ifnar1−/− P14 cells in Prf1−/− mice was also partially recovered (Figures 5A and 5B), in analogy to NK-cell-depleted Bl6 hosts. Similar results were obtained when Ifnar1−/− SM cells were transferred into Prf1−/− mice, with complete recovery of Ifnar1−/− SM cell expansion by day 4 p.i. and partial recovery by day 7 in NK-cell-depleted hosts, and a full recovery in Prf1−/− mice (Figures 5C and 5D). The reduced expansion of WT SM cells at day 7 in Prf1−/− compared to Bl6 mice is due to increased viral burden in the former, as LCMV control is dependent on perforin-mediated CD8+ T cell effector function. The total number of Ifnar1−/− SM cells was comparable between Prf1−/− mice and NK-cell-depleted Bl6 mice. Thus, our results demonstrate that the early negative regulation of Ifnar1−/− T cells by NK cells is perforin dependent, implicating a direct killing mechanism. Next, we investigated whether NK cells were preferentially killing Ifnar1−/− P14 cells. To demonstrate direct killing of CD8+ T cells by NK cells, we established an in vivo killer assay. WT and Ifnar1−/− P14 cells were activated in vivo by VVG2 and LCMV8.7 coinfection, to increase T cell recovery. Activated CD8+ T cells were isolated at day 3 p.i. and transferred into naive or infection-matched hosts, which had been depleted of NK cells or left untreated (Figure 6A). After 6 hr, spleens from host mice were isolated and P14 cell recovery was analyzed. The number of recovered P14 cells in infected hosts was normalized to naive hosts and the percentage of recovery was determined (Figure 6B). We found a significant reduction in the recovery of Ifnar1−/− P14 cells in undepleted hosts compared to WT P14 cells, and this reduced recovery was abolished by NK cell depletion. Also, by examining the ratio of Ifnar1−/− to WT P14 cells in the different hosts, we found a specific reduction in Ifnar1−/− P14 cells in undepleted hosts, which was abolished by NK cell depletion (Figure 6C), indicating preferential in vivo killing of Ifnar1−/− compared to WT P14 cells. Next, we developed an ex vivo killer assay to directly examine the killing of P14 cells by NK cells. WT and Ifnar1−/− P14 cells were activated in NK cell depleted mice in vivo by coinfection with VVG2 and LCMV8.7. At day 3 p.i., WT and Ifnar1−/− P14 cells were sorted to high purity and placed together with day 2 in vivo LCMV activated NK cells (Figure 6D). Following a 6 hr incubation period, T cell killing was visualized by staining with 7-AAD and Annexin V, where double-positive cells represent late apoptotic cells. We observed a strong increase in the percentage of double-positive Ifnar1−/− P14 cells with increasing effector NK to CD8+ T cell target ratios (Figure 6E). This increase in apoptotic Ifnar1−/− P14 cells was reduced to background amounts in the presence of naive NK cells or activated NK cells from Prf1−/− mice. As we observed an increase of apoptotic Ifnar1−/− P14 cells but no increase in apoptotic WT P14 cells, we concluded that Ifnar1−/− P14 cells are specifically rendered susceptible to NK cell mediated killing, whereas T cells that can sense type I IFNs are protected. Because Ifnar1−/− P14 cells were more susceptible to NK-cell-mediated killing, we examined the mechanisms of how Ifnar1−/− P14 cells are specifically recognized by NK cells. From the microarray analysis, we found differential regulation of various molecules involved in NK cell activation or inhibition. To reconfirm differential expression of activating or inhibiting ligands for NK cells, we analyzed expression of a selection of ligands by quantitative real-time PCR (Figure 7A). Among the reconfirmed ligands we found a 3-fold upregulation of the NKG2D activating ligand Mult-1 (Carayannopoulos et al., 2002Carayannopoulos L.N. Naidenko O.V. Fremont D.H. Yokoyama W.M. Cutting edge: murine UL16-binding protein-like transcript 1: a newly described transcript encoding a high-affinity ligand for murine NKG2D.J. Immunol. 2002; 169: 4079-4083Crossref PubMed Scopus (236) Google Scholar) on Ifnar1−/− compared to WT P14 cells. Ifnar1−/− P14 cells had a 2-fold upregulation of Clec2i (Clr-g), the activating ligand for NKR-P1F (Iizuka et al., 2003Iizuka K. Naidenko O.V. Plougastel B.F. Fremont D.H. Yokoyama W.M. Genetically linked C-type lectin-related ligands for the NKRP1 family of natural killer cell receptors.Nat. Immun" @default.
• W2072158757 created "2016-06-24" @default.
• W2072158757 creator A5001478163 @default.
• W2072158757 creator A5008486712 @default.
• W2072158757 creator A5008537578 @default.
• W2072158757 creator A5023634131 @default.
• W2072158757 creator A5038051461 @default.
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• W2072158757 date "2014-06-01" @default.
• W2072158757 modified "2023-10-11" @default.
• W2072158757 title "Type I Interferons Protect T Cells against NK Cell Attack Mediated by the Activating Receptor NCR1" @default.
• W2072158757 cites W1483372876 @default.
• W2072158757 cites W1538826344 @default.
• W2072158757 cites W1549882456 @default.
• W2072158757 cites W1574046283 @default.
• W2072158757 cites W1590883592 @default.
• W2072158757 cites W1608778557 @default.
• W2072158757 cites W1709368598 @default.
• W2072158757 cites W1872050505 @default.
• W2072158757 cites W1874098526 @default.
• W2072158757 cites W1966280572 @default.
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• W2072158757 cites W1993319836 @default.
• W2072158757 cites W2010008322 @default.
• W2072158757 cites W2011647218 @default.
• W2072158757 cites W2016980352 @default.
• W2072158757 cites W2027132663 @default.
• W2072158757 cites W2042295185 @default.
• W2072158757 cites W2043851305 @default.
• W2072158757 cites W2047882003 @default.
• W2072158757 cites W2049238953 @default.
• W2072158757 cites W2064706357 @default.
• W2072158757 cites W2064949202 @default.
• W2072158757 cites W2067758651 @default.
• W2072158757 cites W2070552972 @default.
• W2072158757 cites W2079580203 @default.
• W2072158757 cites W2080683076 @default.
• W2072158757 cites W2085662246 @default.
• W2072158757 cites W2096882227 @default.
• W2072158757 cites W2103565638 @default.
• W2072158757 cites W2111180521 @default.
• W2072158757 cites W2113180936 @default.
• W2072158757 cites W2127834152 @default.
• W2072158757 cites W2134438797 @default.
• W2072158757 cites W2135657057 @default.
• W2072158757 cites W2136034795 @default.
• W2072158757 cites W2144201925 @default.
• W2072158757 cites W2144425033 @default.
• W2072158757 cites W2150098469 @default.
• W2072158757 cites W2153765164 @default.
• W2072158757 cites W2154740067 @default.
• W2072158757 cites W2158387165 @default.
• W2072158757 cites W2168424628 @default.
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