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*Listeria Infections
The Journal of Immunology, 2004, 173: 5652-5658.
Copyright © 2004 by The American Association of Immunologists

Reduced Apoptosis and Ameliorated Listeriosis in TRAIL-Null Mice1

Shi-Jun Zheng*, Jiu Jiang2,{dagger}, Hao Shen{dagger} and Youhai H. Chen3,*

Departments of * Pathology and Laboratory Medicine and {dagger} Microbiology, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104


   Abstract
Top
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Listeriosis is an infectious disease caused by the bacterium Listeria monocytogenes. Although it is well recognized that apoptosis plays a critical role in the pathogenesis of the disease, the molecular mechanisms of cell death in listeriosis remain to be established. We report in this study that mice deficient in TRAIL were partially resistant to primary listeriosis, and blocking TRAIL with a soluble death receptor 5 markedly ameliorated the disease. The numbers of Listeria in the liver and spleen of TRAIL+/+ mice were 10–100 times greater than those in TRAIL–/– mice following primary Listeria infection. This was accompanied by a significant increase in the survival rate of TRAIL–/– mice. Lymphoid and myeloid cell death was significantly inhibited in TRAIL–/– mice, which led to marked enlargement of the spleen. These results establish a critical role for TRAIL in apoptosis during listeriosis.


   Introduction
Top
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
The murine model of systemic Listeria monocytogenes (Lm)4 infection has proven to be an excellent experimental system to study innate and adaptive immune responses to intracellular bacterial pathogens (1, 2). Lm is a facultative, intracellular, Gram-positive organism that replicates within the cytosol of both phagocytic and nonphagocytic cells following bacteria-mediated endocytosis (3). Upon Lm infection, macrophages secrete proinflammatory cytokines such as TNF-{alpha}, IL-1{beta}, IL-6, and IL-12, whereas NK cells secrete IFN-{gamma}. IFN-{gamma} in conjunction with TNF-{alpha} further activates macrophages enhancing their listeriocidal activities (1). During early phase of Lm infection, activated macrophages, neutrophils (4), NK cells, and {gamma}{delta} T cells (5) all play important roles in containing bacterial replication. Adaptive immune responses, which take several days to develop, play no significant roles in the early phase of primary infection.

It is well recognized that Lm infection is associated with severe apoptosis of thymocytes, hepatocytes, and splenocytes (6, 7, 8). Apoptosis of lymphocytes is evident as early as 24 h after Lm infection (7). The underlying mechanisms of apoptosis following Lm infection and its contribution to the host defense are not clear. It has been speculated that apoptosis of infected hepatocytes serves to limit the spreading of the bacterium (9). However, apoptosis of immune cells would diminish host defense and facilitate the spread of intracellular pathogens. Fas-Fas ligand (FasL) interaction does not appear to contribute to apoptosis in primary listeriosis (10, 11). However, the roles of other death receptors in apoptosis during primary Lm infection are not clear.

TRAIL induces apoptosis of tumor cells but not most normal cells (12, 13). In humans, TRAIL interacts with at least four membrane receptors that all belong to the TNFR family. TRAIL receptor 1 (TRAIL-R1; or death receptor (DR) 4) (14) and TRAIL-R2 (DR5), TRICK2, or KILLER) (15, 16) have cytoplasmic death domains, and can activate both caspases and NF-{kappa}B (17). The other two receptors, TRAIL-R3 (decoy receptor 1) and TRAIL-R4 (decoy receptor 2), have truncated death domains. They are not capable of activating the caspase cascade, but may activate NF-{kappa}B and block apoptosis (18). Additionally, osteoprotegerin is a soluble receptor for TRAIL (18, 19), which is known to inhibit osteoclastogenesis and increase bone density. In mice, only one TRAIL death receptor has been identified, which shares the highest sequence homology with human DR5 (16). Similar to humans, mice also have at least two decoy receptors that do not have intracellular domains (17). Recent studies indicate that in addition to inducing apoptosis of tumor cells, TRAIL is also involved in the death of hepatocytes, thymocytes, and neurons (20, 21, 22). To explore the potential roles of TRAIL in Lm-induced apoptosis, we studied listeriosis in mice deficient in TRAIL. We found that TRAIL plays a crucial role in Listeria-induced apoptosis and listeriosis.


   Materials and Methods
Top
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
Mice and infection

Normal C57BL/6 and BALB/c mice were purchased from The Jackson Laboratory (Bar Harbor, ME). TRAIL–/– mice were generated by gene targeting as described (20), and have been backcrossed for >10 generations to BALB/c mice. All mice were housed in the University of Pennsylvania animal facilities under pathogen-free conditions. Virulent Lm (strain 104035) were grown in Brain Heart Infusion (BD Biosciences, San Jose, CA). Log-phase growing cultures were washed twice with PBS and stored at –70°C until use. Mice were injected via tail vein with 200 µl of PBS with or without bacteria. Livers and spleens from infected mice were removed at different time points after Lm infection, and organ homogenates were used for bacterial test.

TRAIL blockade in vivo using soluble DR5 (sDR5)

C57BL/6 mice were injected i.v. with sDR5 (100 µg/mouse) 6 h before i.v. injection of 5 x 104 CFU of Lm. The DR5 injection was repeated 24 and 48 h later. Mice were sacrificed 72 h after the infection.

Histochemistry, fluorescent microscopy, and TUNEL analysis (23)

Tissues were fixed in 10% Formalin and embedded in paraffin. Tissue sections (5 µm) were prepared, stained by H&E or TUNEL as described (23). The number of apoptotic cells in tissue sections was determined by light microscopy in a blinded manner. The total areas of tissue sections were measured using the Image-Pro Plus software (Media Cybernetics, Silver Spring, MD). The degree of apoptosis in the tissue was calculated as follows: the number of apoptotic cells/total area of the sections measured. A total of 10 tissue sections were analyzed for each animal. For fluorescent microscopy, sections were fixed with cold acetone, incubated with anti-CD11b or anti-Listeria Ab and Alexa 488-labeled secondary Ab, stained by TUNEL, and visualized using a Leica DM R fluorescence microscope (Wetzlar, Germany).

Alanine aminotransferase (ALT) assay

Ten- to 11-wk-old TRAIL+/+ and TRAIL–/– BALB/c mice were infected with Lm at a dose of 5 x 103 CFU/0.2 ml/mouse via tail vein. Blood samples were collected, and serum ALT measured using the GP-Transaminase ALAT/GTP kit (Sigma-Aldrich, St. Louis, MO).

Preparation of organ extracts for cytokine assay

Liver and spleen were aseptically removed from the mice and homogenized in RPMI 1640 containing 1% CHAPS (Calbiochem, La Jolla, CA) at a ratio of 1:10 (w/v). The homogenates were centrifuged at 2000 x g for 20 min, and the supernatants were collected for the cytokine assay.

Cytokine assay

Abs for IL-12, IL-6, IL-4, IFN-{gamma}, and TNF-{alpha} were purchased from BD Pharmingen, whereas Abs for IL-1{beta} were purchased from R&D Systems (Minneapolis, MN). All cytokine standards were purchased from BD Pharmingen. Cytokines in organ extracts and the serum were measured by quantitative ELISA per the manufacturer’s recommendations.

Flow cytometry

Cells from spleen and liver were labeled at 4°C with the following Ab reagents: Ly-6G-FITC (Gr-1, Clone: RB6-8C5; Caltag Laboratories, Burlingame, CA), anti-CD11b-Tricolor (Clone: M1/70.15; Caltag Laboratories), neutrophil-PE or neutrophil-FITC (Clone: 7/4; Caltag Laboratories), F4/80-FITC (Clone: CI-A3-1; Caltag Laboratories), anti-CD45R-FITC (B220, RA36B2; Caltag Laboratories), anti-CD4-PE (CT-CD4; Caltag Laboratories), anti-CD8-Tricolor (CT-CD8{alpha}; Caltag Laboratories), anti-NK-PE (Clone: DX5; BD Biosciences), anti-TRAIL-PE (Clone: N2B2; eBioscience, San Diego, CA), and anti-DR5-PE (Clone: MD5-1; eBioscience). After washing, cells were fixed in 1% paraformaldehyde in PBS. Cells were analyzed on a FACSCalibur (BD Biosciences) using the CellQuest program (BD Biosciences). Data were further processed using the FlowJo software (Tree Star, San Carlos, CA).


   Results
Top
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
TRAIL-deficient mice are partially resistant to Lm infection

To explore the roles of TRAIL in host defense against Lm infection, we studied listeriosis in TRAIL–/– BALB/c mice or mice injected with a blocking soluble TRAIL-R. Following a sublethal dose of Lm infection, the numbers of bacteria recovered from the liver and spleen of TRAIL+/+ mice were 10–100 times greater than those from TRAIL–/– mice on days 3 and 7 (Fig. 1, A–D). This was also confirmed by direct Gram’s staining of the tissue (our unpublished observation), which detected much less bacteria in TRAIL–/– sections. Importantly, when injected with a lethal dose of Lm (2.5 x 104 CFU/mouse), the fatality was reduced from 85% (n = 13) in TRAIL+/+ mice to 8% (n = 12) in TRAIL–/– mice 4 days after the infection.



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  		FIGURE 1. Lm loads are markedly reduced in mice deficient in TRAIL. A–D, TRAIL+/+ and TRAIL–/– BALB/c mice (n = 5) were infected with Lm at a dose of 5 x 103 CFU/mouse. The number of bacteria in the liver and spleen of individual mice was determined on days 3 (A and B) and 7 (C and D) postinfection. Horizontal bars in A–D represent the average numbers of Lm of each group. E, TRAIL+/+ C57BL/6 mice (n = 5) were infected with Lm at a dose of 5 x 104 CFU/mouse via tail vein. Six hours before the infection, 24 and 48 h after the infection, each mouse was injected i.v. with 100 µg of sDR5 in PBS or PBS alone. Mice were sacrificed 3 days after the infection and the bacterial numbers in the spleen were determined as described in Materials and Methods. The differences between the two groups were statistically significant (p < 0.05 by t test) for all the panels. A representative of four independent experiments is shown.

 
To ensure that the resistance to listeriosis in TRAIL–/– mice was not due to other abnormalities in these animals, we also tested TRAIL+/+ mice treated with a blocking soluble TRAIL-R. We found that bacterial numbers in the spleen of Lm-infected control mice were five to seven times greater than those in mice injected with the blocking TRAIL-R (Fig. 1E). Taken together, these results demonstrate that TRAIL plays important roles in listeriosis.

Cell death and tissue injuries are reduced in TRAIL-deficient mice during listeriosis

Pathological signs of listeriosis are most evident during the first few days of infection. In TRAIL+/+ mice, severe liver and spleen injury was readily detectable by histochemistry or aminotransferase assay. This was dramatically reduced in TRAIL–/– mice (Fig. 2). The blood ALT level, an indicator of hepatic injury, was significantly higher in TRAIL+/+ than in TRAIL–/– mice (Fig. 2H). To determine whether cell death in listeriosis is mediated through apoptosis, we performed TUNEL analysis of tissue sections. Large numbers of TUNEL+ cells were detected in the spleen of TRAIL+/+ mice 1 day after Lm infection (Fig. 2C), but this was dramatically reduced in TRAIL–/– mice (Fig. 2D). Because the bacterial numbers in the liver and spleen of TRAIL+/+ and TRAIL–/– mice were similar 1 day postinfection (4.1 ± 0.5 x 105 vs 3.6 ± 0.6 x 105, CFU/liver, and 19 ± 3 x 105 vs 16 ± 3 x 105, CFU/spleen, respectively), it may be concluded that the difference in cell death was not due to differences in bacterial load. Furthermore, sDR5 injection dramatically inhibited apoptosis induced by Lm infection (Fig. 3, A–C). Taken together, these results demonstrate that TRAIL plays important roles in the pathogenesis of listeriosis.



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  		FIGURE 2. Cell death and tissue injury are significantly reduced in mice deficient in TRAIL. Mice were treated as described in Fig. 1A. A–F, Spleens were collected at different time points and the degree of apoptosis was determined by TUNEL as described in Materials and Methods. Apoptotic cells are shown in dark brown. Original magnification, x100. G, Quantification of cell death in the spleen. The differences between the two groups on days 1 and 3 are statistically significant (p < 0.01 as determined by ANOVA). A representative of four independent experiments is shown. H, ALT in the serum. Blood samples were collected at different time points and ALT levels determined using the GP-Transaminase ALAT/GTP kit. The differences between the two groups on days 3 and 7 are statistically significant (p < 0.05 as determined by ANOVA). A representative of three independent experiments is shown.

 


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  		FIGURE 3. TRAIL blockade prevents splenocyte apoptosis during listeriosis. A–C, Mice were treated as described in Fig. 1E and sacrificed 3 days after the infection. Spleen sections were incubated with anti-Listeria Ab and Alexa 488-labeled secondary Ab, stained by TUNEL, and visualized under a fluorescence microscope. Original magnification, x100. A, Mice received PBS only. B, Mice received Lm only. Lm are shown in green whereas TUNEL+ cells are shown in red. Original magnification for the inset, x400. C, Mice received both Lm and sDR5. D, Mice were treated as described in Fig. 1A and sacrificed on days 0, 1, and 3. Mononuclear cells were isolated from the liver and flow cytometry was performed as described in Materials and Methods. Histograms show DR5 expression profiles of neutrophils. Control IgG, cells were stained with control IgG, but not anti-DR5 IgG.

 
TRAIL and DR5 are up-regulated during listeriosis

To determine whether listeriosis alters the expression of TRAIL and DR5, we performed flow cytometry using specific Abs (Fig. 3D). We found that NK cells but not other mononuclear cells from spleen and liver dramatically increased TRAIL expression during listeriosis (Table I). Before Lm infection, lymphoid and myeloid cells in the liver and spleen expressed no or very low levels of TRAIL. One day after the Lm infection, ~4% of NK cells expressed TRAIL, and this was increased to 21% and 35% in the spleen and liver, respectively, 3 days after the infection (Table I). Unlike TRAIL, DR5 was widely expressed by multiple cell types including lymphoid and myeloid cells before Lm infection. The expression was further increased 1 and 3 days after the infection especially in myeloid cells (Tables II and III). These results indicate that while many cell types can be targeted by TRAIL to undergo apoptosis, the effector cells of TRAIL action in listeriosis are primarily of NK cell lineage.


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  		Table I. TRAIL expression by NK cells in the spleen and liver during listeriosisa

 

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  		Table II. DR5 expression by lymphocytes and myeloid cells in the spleen during listeriosisa

 

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  		Table III. DR5 expression by lymphocytes and myeloid cells in the liver during listeriosisa

 
Lymphocyte depletion is blocked in TRAIL-deficient mice during listeriosis

It is well recognized that lymphocytes undergo acute apoptosis and are quickly depleted during the early phase of Lm infection (7, 24). Remarkably, this process was significantly blocked in TRAIL–/– mice (Fig. 4A) or mice injected with a soluble blocking TRAIL-R (Fig. 4B). These results indicate that TRAIL is involved in the apoptosis of lymphocytes in Lm-infected mice.



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  		FIGURE 4. Lymphocyte depletion is blocked in the spleen of TRAIL-deficient mice following Lm infection. A, Mice were treated as described in Fig. 1A and sacrificed 3 days after infection. The numbers of CD4+, CD8+, and B220+ cells were determined by flow cytometry. A representative of four independent experiments is shown. The differences between Lm-infected TRAIL+/+ and TRAIL–/– mice are statistically significant (p < 0.05 as determined by ANOVA). B, Mice were treated as in Fig. 1E and sacrificed 3 days after Lm infection. The numbers of CD4+, CD8+, and B220+ cells were determined by flow cytometry. The differences between the two Lm-infected groups are statistically significant (p < 0.05 as determined by ANOVA).

 
Myeloid cell survival and function are enhanced in TRAIL-deficient mice during listeriosis

Myeloid cells are essential for the innate immunity against Lm infection. Neutrophils together with resident macrophages in the spleen and Kuffer’s cells in the liver play critical roles in capturing and destroying Lm. Interestingly, more myeloid cell death occurred in TRAIL+/+ mice than in TRAIL–/– mice as determined by in situ TUNEL and double-staining immunohistochemistry (Fig. 5). Consequently, the numbers of neutrophils and macrophages in both spleen and liver of TRAIL–/– mice were markedly increased as compared with TRAIL+/+ mice following Lm infection (Fig. 6, A and B). This led to significant splenomegaly in TRAIL–/– mice. As expected, mice injected with the sDR5 exhibited similar changes in their myeloid responses to listeriosis as in TRAIL–/– mice (Fig. 6C). These results demonstrate that TRAIL is involved in apoptosis of myeloid cells during acute Lm infection.



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  		FIGURE 5. Myeloid cell death is reduced in the liver and spleen of TRAIL-deficient mice following Lm infection. Mice were treated as in Fig. 1A. Three days after the injection of Lm, liver (A–D) and spleen (E–H) were harvested, sectioned, and stained by FITC-labeled anti-CD11b and TUNEL, and visualized under a fluorescence microscope. Original magnification, x200. CD11b-positive cells are shown in green whereas TUNEL-positive cells are shown in red. Cells in yellow are positive for both CD11b and TUNEL.

 


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  		FIGURE 6. Accumulation of myeloid cells in the liver and spleen of TRAIL-deficient mice following Lm infection. A and B, Mice (n = 4) were treated as described in Fig. 1A and sacrificed 3 days after the infection. Numbers of myeloid cells were determined by flow cytometry with anti-neutrophils, anti-CD11b, and F4/80 Abs. Data shown are mean and SD of neutrophils and macrophages for spleen (A) and liver (B). The differences between Lm-infected TRAIL+/+ and TRAIL–/– mice are statistically significant (p < 0.05 as determined by ANOVA). Four independent experiments were performed with similar results. C, Mice (n = 3) were treated as in Fig. 1E. Three days after Lm infection, splenocytes were isolated, stained for neutrophils and macrophages, and analyzed by flow cytometry as described above. The differences between the two Lm-infected groups are statistically significant (p < 0.05 as determined by ANOVA). Data are representative of two independent experiments.

 
In addition to the increase in the number of mononuclear cells in TRAIL–/– mice, the cytokines produced by them were also elevated. Specifically, 3 days after Lm infection, the concentrations of IFN-{gamma}, IL-6, and IL-1{beta} in the liver extracts of TRAIL–/– mice were 15 ± 0.5 ng/ml, 173 ± 5 pg/ml, and 252 ± 43 pg/ml, respectively, as compared with 11 ± 0.9 ng/ml, 116 ± 14 pg/ml, and 154 ± 7 pg/ml, respectively, of TRAIL+/+ mice (n = 4, p < 0.05). Similarly, at the same time point, the concentrations of IFN-{gamma}, IL-6, and IL-4 in the spleen extracts of TRAIL–/– mice were 10.2 ± 2 ng/ml, 523 ± 36 pg/ml, and 20 ± 0.7 pg/ml, respectively, as compared with 7 ± 0.2 ng/ml, 334 ± 2 pg/ml, and 13 ± 2 pg/ml, respectively, of TRAIL+/+ mice (n = 4, p < 0.05). Furthermore, serum levels of IL-12 and IFN-{gamma} were also significantly increased in TRAIL–/– animals as shown in Fig. 7, A and B. IL-1 and TNF-{alpha} levels in the sera were not significantly different between the two groups (data not shown). Finally, when cultured in vitro, more IL-12 and IL-6 were produced by peritoneal macrophages of Lm-infected TRAIL–/– mice (Fig. 7, C and D). However, when wild-type and TRAIL-deficient macrophages from uninfected mice were compared in the same assay, no significant differences were observed (our unpublished observation). These results suggest that macrophages from Lm-infected TRAIL–/– mice have a higher degree of activation than those from wild-type animals.



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  		FIGURE 7. Increased cytokine production in TRAIL-deficient mice following Lm infection. A and B, Normal and TRAIL-deficient BALB/c mice were infected with Lm as described in Fig. 1A and bled 3 days after the infection. Serum IL-12 and IFN-{gamma} were determined by ELISA as described in Materials and Methods. The differences between Lm-infected TRAIL+/+ and TRAIL–/– mice are statistically significant (p < 0.05 as determined by ANOVA). Data are representative of three independent experiments. C and D, Peritoneal macrophages were collected from normal and TRAIL-deficient BALB/c mice 2 days after infection with Lm as described in Fig. 1A, and cultured for 48 h with or without 10 U/ml IFN-{gamma} and/or 200 pg/ml LPS. IL-6 and IL-12 concentrations in the supernatants were determined by ELISA. The differences between TRAIL+/+ and TRAIL–/– groups following IFN-{gamma} or LPS treatment are statistically significant (p < 0.05 as determined by ANOVA). Med, Medium control. Data are representative of four independent experiments.

 
Taken together, these results indicate that in the absence of TRAIL, myeloid cell responses were significantly enhanced, which may in turn contribute to the improved host resistance to Lm infection in TRAIL–/– mice.


   Discussion
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
TRAIL holds tremendous promise for cancer therapy because of its ability to selectively induce apoptosis of tumor cells but not most normal cells. However, recent studies using cultured normal cells have cast doubt about this theory. Thus, unlike most normal cells, human hepatocytes, thymocytes, and neural cells appear to be sensitive to TRAIL-induced apoptosis (20, 21). In addition, TRAIL is involved in the development and progression of collagen-induced arthritis and streptozotocin-induced diabetes (20, 25). Results reported in this study demonstrate that, in vivo, TRAIL is also involved in apoptosis of myeloid cells and lymphocytes during acute phase of Lm infection. Blocking TRAIL action in mice ameliorates cell death and enhances host defense against Lm infection.

Several lines of evidence indicate that intracellular bacterial pathogens can either induce or block apoptosis, which in turn influences disease progression (26). It is well recognized that Lm infection can induce apoptosis in multiple cell types including thymocytes, hepatocytes, dendritic cells, and peripheral lymphocytes. However, the nature of the molecules mediating this type of cell death is not clear. Our results indicate that TRAIL may be one of those molecules mediating apoptosis during acute phase of Lm infection. It is to be emphasized that experiments described in this study directly test the roles of endogenous TRAIL (most likely membrane-bound TRAIL) in cell death in vivo. This is different from other studies in which exogenous TRAIL was added to the experimental system. Because TRAIL deficiency in our system is global, i.e., affecting all organ systems in mice, it raises the question whether the effects observed on splenic cell death is due to a direct effect of TRAIL on splenocytes or an indirect effect of TRAIL on other cells or systems. In our model of listeriosis, dramatic differences in apoptosis were observed on day 1 (Fig. 2) when the numbers of bacteria in different animals were the same. This may rule out the possibility that bacteria may be directly responsible for the observed differences in apoptosis. Because TRAIL gene mutation is the only known difference between TRAIL+/+ and TRAIL–/– mice at this time point, it is reasonable to conclude that TRAIL is responsible for the difference in splenic cell death. Of note is that the physiological significance of early apoptosis during Lm infection is not clear. Recently, Jiang et al. (27) demonstrated that lymphocyte depletion during primary Lm infection was not Ag-specific. This was based on the finding that nonrelated lymphocytes, but not lymphocytes from P14 transgenic mice, were depleted in recipient mice following infection with gp33 Lm (27).

The innate immune response to Lm involves coordinated interactions between many cell types and the production of numerous cytokines. Neutrophils play a key role in the early defense against Lm. We found that DR5 was highly expressed in neutrophils during listeriosis (Fig. 3D, and Tables II and III) and the numbers of neutrophils in the spleen of TRAIL–/– mice were six times greater than those of TRAIL+/+ mice (Fig. 6A). Similarly, the number of neutrophils was also significantly increased in mice treated with a blocking TRAIL-R (Fig. 6C). Consequently, the numbers of bacteria recovered from the liver and spleen of TRAIL–/– mice were dramatically reduced as compared with those of TRAIL+/+ mice. This suggests that regulation of neutrophil apoptosis by TRAIL may contribute to the pathogenesis of listeriosis. Additionally, survival and functions of macrophages also appear to be regulated by TRAIL, which would in turn affect the host innate response to Lm.

TRAIL shares the highest sequence homology with FasL, which has also been implicated in regulating immunity and infection. However, unlike TRAIL, FasL is not involved in apoptosis early in Lm infection but plays a role in immune responses to the bacterium during the late phases of the infection (10, 11). Results reported in this study clearly establish a role for TRAIL in the innate immune response to Lm infection. Further investigation is needed to test the roles of TRAIL in adaptive immune responses to Lm.


   Acknowledgments
 
We thank Dr. Jacques Peschon (Amgen, Seattle, WA) for kindly providing the breeders of the TRAIL–/– mice. We also thank Dr. Brendan Hilliard (University of Pennsylvania, Philadelphia, PA) for technical support.


   Footnotes
 
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

1 This work was supported by grants from the National Institutes of Health (AI50059, AI055934, AI55934, and NS40188). Back

2 Current address: Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129. Back

3 Address correspondence and reprint requests to Dr. Youhai H. Chen, 614 BRB-II/III, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 421 Curie Boulevard, Philadelphia, PA 19104. E-mail address: yhc{at}mail.med.upenn.edu Back

4 Abbreviations used in this paper: Lm, Listeria monocytogenes; FasL, Fas ligand; ALT, alanine aminotransferase; DR, death receptor; TRAIL-R, TRAIL receptor; sDR5, soluble DR5. Back

Received for publication March 4, 2004. Accepted for publication August 26, 2004.


   References
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Unanue, E. R.. 1997. Studies in listeriosis show the strong symbiosis between the innate cellular system and the T-cell response. Immunol. Rev. 158:11.[Medline]
  2. Edelson, B. T., E. R. Unanue. 2000. Immunity to Listeria infection. Curr. Opin. Immunol. 12:425.[Medline]
  3. Portnoy, D. A., P. S. Jacks, D. J. Hinrichs. 1988. Role of hemolysin for the intracellular growth of Listeria monocytogenes. J. Exp. Med. 167:1459.[Abstract/Free Full Text]
  4. Conlan, J. W., R. J. North. 1994. Neutrophils are essential for early anti-Listeria defense in the liver, but not in the spleen or peritoneal cavity, as revealed by a granulocyte-depleting monoclonal antibody. J. Exp. Med. 179:259.[Abstract/Free Full Text]
  5. Mombaerts, P., J. Arnoldi, F. Russ, S. Tonegawa, S. H. Kaufmann. 1993. Different roles of {alpha}{beta} and {gamma}{delta} T cells in immunity against an intracellular bacterial pathogen. Nature 365:53.[Medline]
  6. Rogers, H. W., M. P. Callery, B. Deck, E. R. Unanue. 1996. Listeria monocytogenes induces apoptosis of infected hepatocytes. J. Immunol. 156:679.[Abstract]
  7. Merrick, J. C., B. T. Edelson, V. Bhardwaj, P. E. Swanson, E. R. Unanue. 1997. Lymphocyte apoptosis during early phase of Listeria infection in mice. Am. J. Pathol. 151:785.[Abstract]
  8. Miura, T., S. Nishikawa, S. Sasaki, K. Yamada, S. Hasegawa, D. Mizuki, M. Mizuki, I. Hatayama, K. Sekikawa, Y.-i. Tagawa, et al 2000. Roles of endogenous cytokines in liver apoptosis of mice in lethal Listeria monocytogenes infection. FEMS Immunol. Med. Microbiol. 28:335.[Medline]
  9. Mueller, N. J., R. A. Wilkinson, J. A. Fishman. 2002. Listeria monocytogenes infection in caspase-11-deficient mice. Infect. Immun. 70:2657.[Abstract/Free Full Text]
  10. Fuse, Y., H. Nishimura, K. Maeda, Y. Yoshikai. 1997. CD95 (Fas) may control the expansion of activated T cells after elimination of bacteria in murine listeriosis. Infect. Immun. 65:1883.[Abstract]
  11. Jensen, E. R., A. A. Glass, W. R. Clark, E. J. Wing, J. F. Miller, S. H. Gregory. 1998. Fas (CD95)-dependent cell-mediated immunity to Listeria monocytogenes. Infect. Immun. 66:4143.[Abstract/Free Full Text]
  12. Wiley, S. R., K. Schooley, P. J. Smolak, W. S. Din, C. P. Huang, J. K. Nicholl, G. R. Sutherland, T. D. Smith, C. Rauch, C. A. Smith, et al 1995. Identification and characterization of a new member of the TNF family that induces apoptosis. Immunity 3:673.[Medline]
  13. Pan, G., K. O’Rourke, A. M. Chinnaiyan, R. Gentz, R. Ebner, J. Ni, V. M. Dixit. 1997. The receptor for the cytotoxic ligand TRAIL. Science 276:111.[Abstract/Free Full Text]
  14. Pan, G., J. Ni, Y.-F. Wei, G.-L. Yu, R. Gentz, V. M. Dixit. 1997. An antagonist decoy receptor and a death domain-containing receptor for TRAIL. Science 277:815.[Abstract/Free Full Text]
  15. Walczak, H., M. A. Degli-Esposti, R. S. Johnson, P. J. Smolak, J. Y. Waugh, N. Boiani, M. S. Timour, M. J. Gerhart, K. A. Schooley, C. A. Smith, et al 1997. TRAIL-R2: a novel apoptosis-mediating receptor for TRAIL. EMBO J. 16:5386.[Medline]
  16. Wu, G. S., T. F. Burns, Y. Zhan, E. S. Alnemri, W. S. El-Deiry. 1999. Molecular cloning and functional analysis of the mouse homologue of the KILLER/DR5 tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptor. Cancer Res. 59:2770.[Abstract/Free Full Text]
  17. Schneider, P., M. Thome, K. Burns, J. L. Bodmer, K. Hofmann, T. Kataoka, N. Holler, J. Tschopp. 1997. TRAIL receptors 1 (DR4) and 2 (DR5) signal FADD-dependent apoptosis and activate NF-{kappa}B. Immunity 7:831.[Medline]
  18. Degli-Esposti, M. A., W. C. Dougall, P. J. Smolak, J. Y. Waugh, C. A. Smith, R. G. Goodwin. 1997. The novel receptor TRAIL-R4 induces NF-{kappa}B and protects against TRAIL-mediated apoptosis, yet retains an incomplete death domain. Immunity 7:813.[Medline]
  19. Sheridan, J. P., S. A. Marsters, R. M. Pitti, A. Gurney, M. Skubatch, D. Baldwin, L. Ramakrishnan, C. L. Gray, K. Baker, W. I. Wood, et al 1997. Control of TRAIL-induced apoptosis by a family of signaling and decoy receptors. Science 277:818.[Abstract/Free Full Text]
  20. Lamhamedi-Cherradi, S.-E., S. Zheng, K. Maguschak, J. Peschon, Y. H. Chen. 2003. Defective thymocyte apoptosis and accelerated autoimmune diseases in TRAIL–/– mice. Nat. Immunol. 4:255.[Medline]
  21. Martin-Villalba, A., I. Herr, I. Jeremias, M. Hahne, R. Brandt, J. Vogel, J. Schenkel, T. Herdegen, K.-M. Debatin. 1999. CD95 ligand (Fas-L/APO-1L) and tumor necrosis factor-related apoptosis-inducing ligand mediate ischemia-induced apoptosis in neurons. J. Neurosci. 19:3809.[Abstract/Free Full Text]
  22. Mundt, B., F. Kuhnel, L. Zender, Y. Paul, H. Tillmann, C. Trautwein, M. P. Manns, S. Kubicka. 2003. Involvement of TRAIL and its receptors in viral hepatitis. FASEB J. 17:94.[Abstract/Free Full Text]
  23. Song, K., Y. Chen, R. Goke, A. Wilmen, C. Seidel, A. Goke, B. Hilliard, Y. Chen. 2000. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an inhibitor of autoimmune inflammation and cell cycle progression. J. Exp. Med. 191:1095.[Abstract/Free Full Text]
  24. Mannering, S. I., J. Zhong, C. Cheers. 2002. T-cell activation, proliferation and apoptosis in primary Listeria monocytogenes infection. Immunology 106:87.[Medline]
  25. Lamhamedi-Cherradi, S.-E., S. Zheng, R. Tisch, Y. H. Chen. 2003. Critical roles of tumor necrosis factor-related apoptosis-inducing ligand in type I diabetes. Diabetes 52:2274.[Abstract/Free Full Text]
  26. Gao, L.-Y., Y. A. Kwaik. 2000. The modulation of host cell apoptosis by intracellular bacterial pathogens. Trends Microbiol. 8:306.[Medline]
  27. Jiang, J., L. L. Lau, H. Shen. 2003. Selective depletion of nonspecific T cells during the early stage of immune responses to infection. J. Immunol. 171:4352.[Abstract/Free Full Text]



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