Intraepithelial lymphocyte-derived interferon-γ evokes enterocyte apoptosis with parenteral nutrition in mice

2003 ◽  
Vol 284 (4) ◽  
pp. G629-G637 ◽  
Author(s):  
Hua Yang ◽  
Yongyi Fan ◽  
Daniel H. Teitelbaum

Total parenteral nutrition (TPN) results in an increase in intraepithelial lymphocyte (IEL)-derived interferon-γ (IFN-γ) expression as well as an increase in epithelial cell (EC) apoptosis. This study examined the role that IEL-derived IFN-γ has in the increase in EC apoptosis. Mice received either TPN or oral feedings for 7 days. Small bowel EC apoptosis significantly rose in mice receiving TPN. The administration of TPN also significantly increased IEL-derived IFN-γ and Fas ligand (FasL) expression. EC apoptosis in IFN-γ knockout (IFNKO) mice that received TPN was significantly lower than in wild-type TPN mice. Sensitivity of EC to Fas-mediated apoptosis in IFNKO mice was significantly lower than in wild-type TPN mice. Apoptosis in Fas-deficient and FasL-deficient mice that received TPN was significantly lower than in wild-type mice that received TPN. The TPN-induced increase in IFN-γ expression appears to result in an increase in Fas-L expression and EC sensitivity to Fas, with a resultant increase in EC apoptosis. This may well be one of the mediators of increased EC apoptosis observed with TPN administration.

2007 ◽  
Vol 75 (11) ◽  
pp. 5338-5345 ◽  
Author(s):  
Kee-Jong Hong ◽  
Jason R. Wickstrum ◽  
Hung-Wen Yeh ◽  
Michael J. Parmely

ABSTRACT The production of gamma interferon (IFN-γ) is a key step in the protective innate immune response to Francisella tularensis. Natural killer cells and T cells in the liver are important sources of this cytokine during primary F. tularensis infections, and interleukin-12 (IL-12) appears to be an essential coactivating cytokine for hepatic IFN-γ expression. The present study was undertaken to determine whether or not macrophages (Mφ) or dendritic cells (DC) provide coactivating signals for the liver IFN-γ response in vitro, whether IL-12 mediates these effects, and whether Toll-like receptor (TLR) signaling is essential to induce this costimulatory activity. Both bone marrow-derived Mφ and DC significantly augmented the IFN-γ response of F. tularensis-challenged liver lymphocytes in vitro. While both cell types produced IL-12p40 in response to F. tularensis challenge, only DC secreted large quantities of IL-12p70. DC from both IL-12p35-deficient and TLR2-deficient mice failed to produce IL-12p70 and did not costimulate liver lymphocytes for IFN-γ production in response to viable F. tularensis organisms. Conversely, liver lymphocytes from TLR2-deficient mice cocultured with wild-type accessory cells produced IFN-γ at levels comparable to those for wild-type hepatic lymphocytes. These findings indicate that TLR2 controls hepatic lymphocyte IFN-γ responses to F. tularensis by regulating DC IL-12 production. While Mφ also coinduced hepatic IFN-γ production in response to F. tularensis, they did so in a fashion less dependent on TLR2.


2005 ◽  
Vol 73 (4) ◽  
pp. 2101-2108 ◽  
Author(s):  
Laurence U. Buxbaum ◽  
Phillip Scott

ABSTRACT Infection of C57BL/6 (B6) mice with Leishmania mexicana is associated with a minimal immune response and chronic disease. Here we show that B6 interleukin 10−/− (IL-10−/−) mice resolve their lesions and exhibit increased gamma interferon (IFN-γ), nitric oxide production, and delayed-type hypersensitivity. This enhanced resistance was dependent upon IL-12p40, since treatment of L. mexicana-infected IL-10−/− mice with anti-IL-12p40 monoclonal antibody abrogated healing. Antibody-opsonized L. mexicana induced IL-10 production by B6 macrophages in vitro, implicating antibody binding to Fc receptors as a mechanism involved in IL-10 production in this infection. Furthermore, B6 FcRγ−/− mice resolve L. mexicana lesions, and lymph node cells from these mice produced less IL-10 and more IFN-γ than cells from infected wild-type mice. These data demonstrate that removal of IL-10 or FcγR leads to resolution of L. mexicana disease and support a model in which ligation of FcγR by L. mexicana-bound immunoglobulin G promotes IL-10 production, leading to chronic disease.


2005 ◽  
Vol 79 (21) ◽  
pp. 13509-13518 ◽  
Author(s):  
Jürgen Hausmann ◽  
Axel Pagenstecher ◽  
Karen Baur ◽  
Kirsten Richter ◽  
Hanns-Joachim Rziha ◽  
...  

ABSTRACT Borna disease virus (BDV) frequently causes meningoencephalitis and fatal neurological disease in young but not old mice of strain MRL. Disease does not result from the virus-induced destruction of infected neurons. Rather, it is mediated by H-2 k -restricted antiviral CD8 T cells that recognize a peptide derived from the BDV nucleoprotein N. Persistent BDV infection in mice is not spontaneously cleared. We report here that N-specific vaccination can protect wild-type MRL mice but not mutant MRL mice lacking gamma interferon (IFN-γ) from persistent infection with BDV. Furthermore, we observed a significant degree of resistance of old MRL mice to persistent BDV infection that depended on the presence of CD8 T cells. We found that virus initially infected hippocampal neurons around 2 weeks after intracerebral infection but was eventually cleared in most wild-type MRL mice. Unexpectedly, young as well as old IFN-γ-deficient MRL mice were completely susceptible to infection with BDV. Moreover, neurons in the CA1 region of the hippocampus were severely damaged in most diseased IFN-γ-deficient mice but not in wild-type mice. Furthermore, large numbers of eosinophils were present in the inflamed brains of IFN-γ-deficient mice but not in those of wild-type mice, presumably because of increased intracerebral synthesis of interleukin-13 and the chemokines CCL1 and CCL11, which can attract eosinophils. These results demonstrate that IFN-γ plays a central role in host resistance against infection of the central nervous system with BDV and in clearance of BDV from neurons. They further indicate that IFN-γ may function as a neuroprotective factor that can limit the loss of neurons in the course of antiviral immune responses in the brain.


2005 ◽  
Vol 202 (5) ◽  
pp. 583-588 ◽  
Author(s):  
Mark J. Smyth ◽  
Jeremy Swann ◽  
Erika Cretney ◽  
Nadeen Zerafa ◽  
Wayne M. Yokoyama ◽  
...  

The activation NKG2D receptor has been shown to play an important role in the control of experimental tumor growth and metastases expressing ligands for NKG2D; however, a function for this recognition pathway in host protection from de novo tumorigenesis has never been demonstrated. We show that neutralization of NKG2D enhances the sensitivity of wild-type (WT) C57BL/6 and BALB/c mice to methylcholanthrene (MCA)-induced fibrosarcoma. The importance of the NKG2D pathway was additionally illustrated in mice deficient for either IFN-γ or tumor necrosis factor–related apoptosis-inducing ligand, whereas mice depleted of natural killer cells, T cells, or deficient for perforin did not display any detectable NKG2D phenotype. Furthermore, IL-12 therapy preventing MCA-induced sarcoma formation was also largely dependent on the NKG2D pathway. Although NKG2D ligand expression was variable or absent on sarcomas emerging in WT mice, sarcomas derived from perforin-deficient mice were Rae-1+ and immunogenic when transferred into WT syngeneic mice. These findings suggest an important early role for the NKG2D in controlling and shaping tumor formation.


2016 ◽  
Vol 213 (4) ◽  
pp. 585-603 ◽  
Author(s):  
David Langlais ◽  
Luis B. Barreiro ◽  
Philippe Gros

IRF8 and IRF1 are transcriptional regulators that play critical roles in the development and function of myeloid cells, including activation of macrophages by proinflammatory signals such as interferon-γ (IFN-γ). Loss of IRF8 or IRF1 function causes severe susceptibility to infections in mice and in humans. We used chromatin immunoprecipitation sequencing and RNA sequencing in wild type and in IRF8 and IRF1 mutant primary macrophages to systematically catalog all of the genes bound by (cistromes) and transcriptionally activated by (regulomes) IRF8, IRF1, PU.1, and STAT1, including modulation of epigenetic histone marks. Of the seven binding combinations identified, two (cluster 1 [IRF8/IRF1/STAT1/PU.1] and cluster 5 [IRF1/STAT1/PU.1]) were found to have a major role in controlling macrophage transcriptional programs both at the basal level and after IFN-γ activation. They direct the expression of a set of genes, the IRF8/IRF1 regulome, that play critical roles in host inflammatory and antimicrobial defenses in mouse models of neuroinflammation and of pulmonary tuberculosis, respectively. In addition, this IRF8/IRF1 regulome is enriched for genes mutated in human primary immunodeficiencies and with loci associated with several inflammatory diseases in humans.


2003 ◽  
Vol 197 (6) ◽  
pp. 703-709 ◽  
Author(s):  
Nancy Wood ◽  
Matthew J. Whitters ◽  
Bruce A. Jacobson ◽  
JoAnn Witek ◽  
Joseph P. Sypek ◽  
...  

Interleukin (IL)-13 has recently been shown to play important and unique roles in asthma, parasite immunity, and tumor recurrence. At least two distinct receptor components, IL-4 receptor (R)α and IL-13Rα1, mediate the diverse actions of IL-13. We have recently described an additional high affinity receptor for IL-13, IL-13Rα2, whose function in IL-13 signaling is unknown. To better appreciate the functional importance of IL-13Rα2, mice deficient in IL-13Rα2 were generated by gene targeting. Serum immunoglobulin E levels were increased in IL-13Rα2−/− mice despite the fact that serum IL-13 was absent and immune interferon γ production increased compared with wild-type mice. IL-13Rα2–deficient mice display increased bone marrow macrophage progenitor frequency and decreased tissue macrophage nitric oxide and IL-12 production in response to lipopolysaccharide. These results are consistent with a phenotype of enhanced IL-13 responsiveness and demonstrate a role for endogenous IL-13 and IL-13Rα2 in regulating immune responses in wild-type mice.


2001 ◽  
Vol 69 (2) ◽  
pp. 906-911 ◽  
Author(s):  
Abhay R. Satoskar ◽  
Marcelo Bozza ◽  
Miriam Rodriguez Sosa ◽  
Guoshing Lin ◽  
John R. David

ABSTRACT To determine the role of endogenous migration-inhibitory factor (MIF) in the development of protective immunity against cutaneous leishmaniasis, we analyzed the course of cutaneous Leishmania major infection in MIF gene-deficient mice (MIF−/−) and wild-type (MIF+/+) mice. Following cutaneous L. major infection, MIF−/− mice were susceptible to disease and developed significantly larger lesions and greater parasite burdens than MIF+/+ mice. Interestingly, antigen-stimulated lymph node cells from MIF−/− mice produced more interleukin-4 (IL-4) and gamma interferon (IFN-γ) than those from MIF+/+ mice, although the differences were statistically not significant. IFN-γ-activated resting peritoneal macrophages from MIF−/− mice showed impaired macrophage leishmanicidal activity and produced significantly lower levels of nitric oxide and superoxide in vitro. The macrophages from MIF−/− mice, however, produced much more IL-6 than macrophages from wild-type mice. These findings demonstrate that endogenous MIF plays an important role in the development of protective immunity against L. majorin vivo. Furthermore, they indicate that the susceptibility of MIF−/− mice to L. major infection is due to impaired macrophage leishmanicidal activity rather than dysregulation of Th1 and Th2 responses.


2001 ◽  
Vol 194 (2) ◽  
pp. 165-172 ◽  
Author(s):  
Yongkang Zhang ◽  
Ron Apilado ◽  
John Coleman ◽  
Shlomo Ben-Sasson ◽  
Sharon Tsang ◽  
...  

T helper cell (Th)1-primed CD4 T cells from wild-type donors make little interleukin (IL)-4 when restimulated under Th2 conditions. However, such restimulation of Th1-primed cells from interferon (IFN)-γ2/− or IFN-γ receptor (IFN-γR)−/− mice resulted in substantial production of IL-4 and other Th2 cytokines. Adding IFN-γ to the priming culture markedly diminished the capacity of Th1-primed IFN-γ2/− cells to express IL-4. Even IFN-γ–producing cells from IFN-γR−/− mice could acquire IL-4–producing capacity. Thus, IFN-γ is not required for the development of IFN-γ–producing capacity, but it plays a critical role in suppressing the IL-4–producing potential of Th1 cells.


2003 ◽  
Vol 285 (2) ◽  
pp. F319-F325 ◽  
Author(s):  
Naoko Yokota ◽  
Melissa Burne-Taney ◽  
Lorraine Racusen ◽  
Hamid Rabb

Recent data support a modulatory role for CD4 T cells in experimental renal ischemia-reperfusion injury (IRI). CD4 T cells can functionally differentiate to either a Th1 (IFN-γ producing) or the counterbalancing Th2 (IL-4) phenotype. The enzymes signal transducers and activators of transcription (STAT) 4 and STAT6 regulate Th1 or Th2 differentiation and cytokine production, respectively. We therefore hypothesized that mice that were STAT4 deficient would be protected from renal IRI and that STAT6-deficient mice would have a more severe course. Intracellular cytokine staining of splenocytes from STAT4–/– or STAT6–/– exhibited distinct IFN-γ and IL-4 cytokine expression profiles. STAT6–/– had markedly worse renal function and tubular injury postischemia compared with wild type. STAT4–/– had only mildly improved function. Renal phagocyte infiltration and ICAM-1 upregulation were similar in STAT4–/–, STAT6–/–, and wild type. To evaluate if the mechanism of the marked worsening in the STAT6–/– mice could be due to IL-4 deficiency, IL-4-deficient mice were studied and had similar postischemic phenotype to STAT6–/– mice. These data demonstrate that the STAT6 pathway has a major protective role in renal IRI. IL-4 deficiency is a likely mechanism underlying the STAT6 effect. A “yin-yang” role for inflammation is emerging in renal IRI, similar to recent observations in atherosclerosis.


2001 ◽  
Vol 69 (9) ◽  
pp. 5573-5576 ◽  
Author(s):  
Sandra K. Halonen ◽  
Gregory A. Taylor ◽  
Louis M. Weiss

ABSTRACT Toxoplasma gondii is an important pathogen in the central nervous system, causing a severe and often fatal encephalitis in patients with AIDS. Gamma interferon (IFN-γ) is the main cytokine preventing reactivation of Toxoplasma encephalitis in the brain. Microglia are important IFN-γ-activated effector cells controlling the growth of T. gondii in the brain via a nitric oxide (NO)-mediated mechanism. IFN-γ can also activate astrocytes to inhibit the growth of T. gondii. Previous studies found that the mechanism in murine astrocytes is independent of NO and all other known anti-Toxoplasma mechanisms. In this study we investigated the role of IGTP, a recently identified IFN-γ-regulated gene, in IFN-γ inhibition of T. gondii in murine astrocytes. Primary astrocytes were cultivated from IGTP-deficient mice, treated with IFN-γ, and then tested for anti-Toxoplasma activity. In wild-type astrocytesT. gondii growth was significantly inhibited by IFN-γ, whereas in astrocytes from IGTP-deficient mice IFN-γ did not cause a significant inhibition of growth. Immunoblot analysis confirmed that IFN-γ induced significant levels of IGTP in wild-type murine astrocytes within 24 h. These results indicate that IGTP plays a central role in the IFN-γ-induced inhibition of T. gondii in murine astrocytes.


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