Analysis of Virulence and Inflammatory Potential of Shigella flexneri Purine Biosynthesis Mutants

ABSTRACT Several Shigella flexneri mutants with defects in aromatic amino acid and/or purine biosynthesis have been evaluated as vaccines in humans or in animal models. To be suitable as a vaccine, a mutant has to show virulence attenuation, minimal reactogenicity, and a good immunogenic potential in animal models. With this aim, we have constructed five S. flexneri 5 (wild-type strain M90T) mutants with inactivation of one or two of the loci purEK, purHD, and guaBA, governing early or late steps of purine biosynthesis. The mutants have been analyzed in vitro in cell cultures and in vivo in the Sereny test and in the murine pulmonary model of shigellosis. M90T guaBA, M90T guaBA purEK, M90T guaBA purHD, and M90T purHD purEK gave a negative result in the Sereny test. In contrast, in the murine pulmonary model all of the strains had the same 50% lethal dose as the wild type, except M90T guaBA purHD, which did not result in death of the animals. Nevertheless, bacterial counts in infected lungs, immunohistochemistry, and reverse transcription-PCR analysis of mRNAs for tumor necrosis factor alpha (TNF-α), gamma interferon (IFN-γ), interleukin-1β (IL-1β), IL-6, IL-12, and inducible nitric oxide synthase (iNOS) revealed significant differences among the strains. At 72 h postinfection, M90T guaBA purHD still induced proinflammatory cytokines and factors such as IL-1β, IL-6, TNF-α, and iNOS, along with cytokines such as IL-12 and IFN-γ. Moreover, in the absence of evident lesions in murine tissues, this mutant highly stimulated major histocompatibility complex class II expression, showing a significant ability to activate the innate immunity of the host.

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Respiratory Tract Infection with Mycoplasma pneumoniae in Interleukin-12 Knockout Mice Results in Improved Bacterial Clearance and Reduced Pulmonary Inflammation

Infection and Immunity ◽

10.1128/iai.01249-06 ◽

2006 ◽

Vol 75 (1) ◽

pp. 236-242 ◽

Cited By ~ 19

Author(s):

C. M. Salvatore ◽

M. Fonseca-Aten ◽

K. Katz-Gaynor ◽

A. M. Gomez ◽

A. Mejias ◽

...

Keyword(s):

Respiratory Disease ◽

Mycoplasma Pneumoniae ◽

Pulmonary Inflammation ◽

Airway Hyperreactivity ◽

Interleukin 12 ◽

Enzyme Linked Immunosorbent Assay ◽

Wild Type ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Ifn Γ

ABSTRACT Mycoplasma pneumoniae is a leading cause of pneumonia and is associated with asthma. Evidence links M. pneumoniae respiratory disease severity with interleukin-12 (IL-12) concentration in respiratory secretions. We evaluated the microbiologic, inflammatory, and pulmonary function indices of M. pneumoniae pneumonia in IL-12 (p35) knockout (KO) mice and wild-type (WT) mice to determine the role of IL-12 in M. pneumoniae respiratory disease. Eight-week-old wild-type BALB/c mice and 8-week-old IL-12 (p35) KO BALB/c mice were inoculated once intranasally with 107 CFU of M. pneumoniae. Mice were evaluated at days 2, 4, and 7 after inoculation. Outcome variables included quantitative bronchoalveolar lavage (BAL) M. pneumoniae culture, lung histopathologic scores (HPS), BAL cytokine concentrations determined by enzyme-linked immunosorbent assay (tumor necrosis factor alpha [TNF-α], gamma interferon [IFN-γ], IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, and granulocyte-macrophage colony-stimulating factor) and plethysmography, before and after methacholine, to assess airway obstruction (AO) and airway hyperreactivity (AHR). IL-12 (p35) KO mice infected with M. pneumoniae were found to have significantly lower BAL M. pneumoniae concentrations compared with M. pneumoniae-infected WT mice. Lung HPS and the parenchymal pneumonia subscores (neutrophilic alveolar infiltrate), as well as AO, were significantly lower in infected KO mice. No difference was found for AHR. Infected KO mice had significantly lower BAL concentrations of IFN-γ than WT mice; a trend toward lower BAL concentrations was observed for IL-10 (P = 0.065) and TNF-α (P = 0.078). No differences were found for IL-1β, IL-2, IL-4, IL-5, or IL-6. The lack of IL-12 in experimental M. pneumoniae pneumonia was associated with less severe pulmonary disease and more rapid microbiologic and histologic resolution.

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Cytokine Networking in Lungs of Immunocompetent Mice in Response to Inhaled Aspergillus fumigatus

Infection and Immunity ◽

10.1128/iai.69.3.1554-1560.2001 ◽

2001 ◽

Vol 69 (3) ◽

pp. 1554-1560 ◽

Cited By ~ 79

Author(s):

Joan K. Brieland ◽

Craig Jackson ◽

Fred Menzel ◽

David Loebenberg ◽

Anthony Cacciapuoti ◽

...

Keyword(s):

Aspergillus Fumigatus ◽

Lung Tissue ◽

Lavage Fluid ◽

Pcr Analysis ◽

Pulmonary Aspergillosis ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Factor Alpha ◽

Ifn Γ ◽

Immunocompetent Mice

ABSTRACT Cytokine networking in the lung in response to inhaledAspergillus fumigatus was assessed using a murine model of primary pulmonary aspergillosis in immunocompetent Crl:CF-1 mice. Inhalation of virulent A. fumigatus (6 × 106 CFU) resulted in the induction of interleukin 18 (IL-18), tumor necrosis factor alpha (TNF-α), IL-12, and gamma interferon (IFN-γ) protein in bronchoalveolar lavage fluid and/or lung tissue. Induction of immunoreactive IL-18 preceded induction of TNF-α protein, which preceded induction of immunoreactive IL-12 and IFN-γ. Real-time reverse transcriptase (RT) PCR analysis of infected lung tissue demonstrated that induction of IL-18 protein also preceded induction of pulmonary TNF-α, IL-12, and IFN-γ mRNAs. Mice were subsequently treated with cytokine-specific neutralizing monoclonal antibodies (MAbs) to the IL-18 receptor (anti-IL-18R MAb), TNF-α (anti-TNF-α MAb), IL-12 (anti-IL-12 MAb), and/or IFN-γ (anti-IFN-γ MAb), and effects on intrapulmonary cytokine activity and growth of A. fumigatuswere assessed in infected lung homogenates. Simultaneous neutralization of IL-12 and IL-18 resulted in decreased levels of immunoreactive TNF-α, while neutralization of IL-18, TNF-α, or IL-12 alone or of IL-18 and IL-12 together resulted in decreased levels of immunoreactive IFN-γ. Simultaneous neutralization of IL-12 and IL-18 or neutralization of TNF-α alone or in combination with IL-12, IL-18, or IFN-γ also resulted in a significant increase inA. fumigatus CFU in lung tissue. Taken together, these results demonstrate that endogenous IL-18, IL-12, and TNF-α, through their modulatory effects on both intrapulmonary cytokine activity and growth of A. fumigatus, play key roles in host defense against primary pulmonary aspergillosis.

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Granulocyte-Macrophage Colony-Stimulating Factor-Deficient Mice Have Impaired Resistance to Blood-Stage Malaria

Infection and Immunity ◽

10.1128/iai.69.1.129-136.2001 ◽

2001 ◽

Vol 69 (1) ◽

pp. 129-136 ◽

Cited By ~ 49

Author(s):

Julie Riopel ◽

MiFong Tam ◽

Karkada Mohan ◽

Michael W. Marino ◽

Mary M. Stevenson

Keyword(s):

Blood Stage ◽

Colony Stimulating Factor ◽

Necrosis Factor Alpha ◽

Gm Csf ◽

Tnf Α ◽

Macrophage Colony Stimulating Factor ◽

Ifn Γ ◽

Macrophage Colony ◽

Stimulating Factor ◽

Blood Stage Malaria

ABSTRACT The contribution of granulocyte-macrophage colony-stimulating factor (GM-CSF), a hematopoietic and immunoregulatory cytokine, to resistance to blood-stage malaria was investigated by infecting GM-CSF-deficient (knockout [KO]) mice with Plasmodium chabaudi AS. KO mice were more susceptible to infection than wild-type (WT) mice, as evidenced by higher peak parasitemia, recurrent recrudescent parasitemia, and high mortality. P. chabaudiAS-infected KO mice had impaired splenomegaly and lower leukocytosis but equivalent levels of anemia compared to infected WT mice. Both bone marrow and splenic erythropoiesis were normal in infected KO mice. However, granulocyte-macrophage colony formation was significantly decreased in these tissues of uninfected and infected KO mice, and the numbers of macrophages in the spleen and peritoneal cavity were significantly lower than in infected WT mice. Serum levels of gamma interferon (IFN-γ) were found to be significantly higher in uninfected KO mice, and the level of this cytokine was not increased during infection. In contrast, IFN-γ levels were significantly above normal levels in infected WT mice. During infection, tumor necrosis factor alpha (TNF-α) levels were significantly increased in KO mice and were significantly higher than TNF-α levels in infected WT mice. Our results indicate that GM-CSF contributes to resistance to P. chabaudi AS infection and that it is involved in the development of splenomegaly, leukocytosis, and granulocyte-macrophage hematopoiesis. GM-CSF may also regulate IFN-γ and TNF-α production and activity in response to infection. The abnormal responses seen in infected KO mice may be due to the lack of GM-CSF during development, to the lack of GM-CSF in the infected mature mice, or to both.

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Changes in Antigen-Specific Cytokine and Chemokine Responses to Plasmodium falciparum Antigens in a Highland Area of Kenya after a Prolonged Absence of Malaria Exposure

Infection and Immunity ◽

10.1128/iai.01924-14 ◽

2014 ◽

Vol 82 (9) ◽

pp. 3775-3782 ◽

Cited By ~ 6

Author(s):

Lyticia A. Ochola ◽

Cyrus Ayieko ◽

Lily Kisia ◽

Ng'wena G. Magak ◽

Estela Shabani ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Severe Disease ◽

Clinical Malaria ◽

Necrosis Factor Alpha ◽

Content Type ◽

Highland Area ◽

Cytokine Responses ◽

Increased Risk ◽

Tnf Α ◽

Ifn Γ

ABSTRACTIndividuals naturally exposed toPlasmodium falciparumlose clinical immunity after a prolonged lack of exposure.P. falciparumantigen-specific cytokine responses have been associated with protection from clinical malaria, but the longevity ofP. falciparumantigen-specific cytokine responses in the absence of exposure is not well characterized. A highland area of Kenya with low and unstable malaria transmission provided an opportunity to study this question. The levels of antigen-specific cytokines and chemokines associated in previous studies with protection from clinical malaria (gamma interferon [IFN-γ], interleukin-10 [IL-10], and tumor necrosis factor alpha [TNF-α]), with increased risk of clinical malaria (IL-6), or with pathogenesis of severe disease in malaria (IL-5 and RANTES) were assessed by cytometric bead assay in April 2008, October 2008, and April 2009 in 100 children and adults. During the 1-year study period, none had an episode of clinicalP. falciparummalaria. Two patterns of cytokine responses emerged, with some variation by antigen: a decrease at 6 months (IFN-γ and IL-5) or at both 6 and 12 months (IL-10 and TNF-α) or no change over time (IL-6 and RANTES). These findings document thatP. falciparumantigen-specific cytokine responses associated in prior studies with protection from malaria (IFN-γ, TNF-α, and IL-10) decrease significantly in the absence ofP. falciparumexposure, whereas those associated with increased risk of malaria (IL-6) do not. The study findings provide a strong rationale for future studies of antigen-specific IFN-γ, TNF-α, and IL-10 responses as biomarkers of increased population-level susceptibility to malaria after prolonged lack ofP. falciparumexposure.

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Gamma Interferon and Lipopolysaccharide Interact at the Level of Transcription To Induce Tumor Necrosis Factor Alpha Expression

Infection and Immunity ◽

10.1128/iai.69.5.2847-2852.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 2847-2852 ◽

Cited By ~ 18

Author(s):

Julia Y. Lee ◽

Kathleen E. Sullivan

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis Factor Alpha ◽

Tumor Necrosis ◽

Gamma Interferon ◽

Necrosis Factor Alpha ◽

Rnase Protection ◽

Tnf Α ◽

Factor Alpha ◽

Ifn Γ ◽

Necrosis Factor

ABSTRACT Lipopolysaccharide (LPS) is a very potent inducer of tumor necrosis factor alpha (TNF-α) expression from monocytes and macrophages. Another inflammatory cytokine, gamma interferon (IFN-γ), can potentiate the effects of LPS, but the mechanism is not thoroughly understood. Previous reports emphasized the ability of IFN-γ to upregulate CD14 expression (the receptor for LPS), and nearly all studies have utilized sequential stimulation with IFN-γ followed by LPS to exploit this phenomenon. This study demonstrates that IFN-γ can upregulate the effect of LPS at the level of transcription. Human monoblastic Mono-Mac-6 cells produced up to threefold-greater levels of TNF-α when simultaneously stimulated with LPS and IFN-γ compared to treatment with LPS alone. RNase protection studies showed a similar increase in RNA beginning as early as within 30 min. The synthesis of TNF-α mRNA in IFN-γ- and LPS-treated Mono-Mac-6 cells was also temporally prolonged even though the message turnover rate was identical to that seen in LPS stimulated cells. The modulatory effect of IFN-γ may be mediated by Jak2.

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Intestinal Intraepithelial Lymphocytes Sustain the Epithelial Barrier Function against Eimeria vermiformis Infection

Infection and Immunity ◽

10.1128/iai.02024-05 ◽

2006 ◽

Vol 74 (9) ◽

pp. 5292-5301 ◽

Cited By ~ 68

Author(s):

Kyoko Inagaki-Ohara ◽

Fitriya Nurannisa Dewi ◽

Hajime Hisaeda ◽

Adrian L. Smith ◽

Fumiko Jimi ◽

...

Keyword(s):

Transforming Growth Factor ◽

Cell Monolayer ◽

Direct Interaction ◽

Intraepithelial Lymphocytes ◽

Epithelial Barrier ◽

Necrosis Factor Alpha ◽

Intestinal Intraepithelial Lymphocytes ◽

Tnf Α ◽

Ifn Γ ◽

Eimeria Vermiformis

ABSTRACT Eimeria spp. are intracellular protozoa that infect intestinal epithelia of most vertebrates, causing coccidiosis. Intestinal intraepithelial lymphocytes (IEL) that reside at the basolateral site of epithelial cells (EC) have immunoregulatory and immunoprotective roles against Eimeria spp. infection. However, it remains unknown how IEL are involved in the regulation of epithelial barrier during Eimeria sp. infection. Here, we demonstrated two distinct roles of IEL against infection with Eimeria vermiformis, a murine pathogen: production of cytokines to induce protective immunity and expression of junctional molecules to preserve epithelial barrier. The number of IEL markedly increased when oocyst production reached a peak. During infection, IEL increased production of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and decreased transforming growth factor β (TGF-β) production. Addition of IFN-γ and TNF-α or supernatants obtained from cultured IEL from E. vermiformis-infected mice reduced transepithelial electrical resistance (TER) in a confluent CMT93 cell monolayer, a murine intestine-derived epithelial line, but antibodies against these cytokines suppressed the decline of TER. Moreover, TGF-β attenuated the damage of epithelial monolayer and changes in TER caused by IFN-γ and TNF-α. The expression of junctional molecules by EC was decreased when IEL produced a high level of IFN-γ and TNF-α and a low level of TGF-β in E. vermiformis-infected mice. Interestingly, IEL constantly expressed junctional molecules and a coculture of EC with IEL increased TER. These results suggest that IEL play important multifunctional roles not only in protection of the epithelium against E. vermiformis-induced change by cytokine production but also in direct interaction with the epithelial barrier when intra-EC junctions are down-regulated.

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A Defect in Interleukin-10 Leads to Enhanced Malarial Disease in Plasmodium chabaudi chabaudi Infection in Mice

Infection and Immunity ◽

10.1128/iai.67.9.4435-4442.1999 ◽

1999 ◽

Vol 67 (9) ◽

pp. 4435-4442 ◽

Cited By ~ 166

Author(s):

Ching Li ◽

Inés Corraliza ◽

Jean Langhorne

Keyword(s):

Body Weight ◽

Knockout Mice ◽

Interleukin 10 ◽

Plasmodium Chabaudi ◽

Double Knockout ◽

Direct Stimulation ◽

Necrosis Factor Alpha ◽

Glucose Levels ◽

Tnf Α ◽

Ifn Γ

ABSTRACT Infection of interleukin-10 (IL-10)-nonexpressing (IL-10−/−) mice with Plasmodium chabaudi chabaudi (AS) leads to exacerbated pathology in female mice and death in a proportion of them. Hypoglycemia, hypothermia, and loss in body weight were significantly greater in female IL-10−/−mice than in male knockout mice and all wild-type (WT) mice during the acute phase of infection. At this time, both female and male IL-10−/− mice produced more gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and IL-12p40 mRNA than their respective WT counterparts. Inactivation of IFN-γ in IL-10−/− mice by the injection of anti-IFN-γ antibodies or by the generation of IL-10−/− IFN-γ receptor−/− double-knockout mice resulted in reduced mortality but did not affect body weight, temperature, or blood glucose levels. The data suggest that IFN-γ-independent pathways may be responsible for these pathological features of P. chabaudimalaria and may be due to direct stimulation of TNF-α by the parasite. Since male and female knockout mice both produce more inflammatory cytokines than their WT counterparts, it is likely that the mortality seen in females is due to the nature or magnitude of the response to these cytokines rather than the amount of IFN-γ or TNF-α produced.

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Association between tumor necrosis factor-α gene-1031T/C promoter polymorphism and endometriosis in a European population

Hormone Molecular Biology and Clinical Investigation ◽

10.1515/hmbci-2019-0033 ◽

2019 ◽

Vol 40 (2) ◽

Cited By ~ 1

Author(s):

Anastasia Drakou ◽

Despoina Mavrogianni ◽

Konstantinos Ntzeros ◽

Athanasios Protopapas ◽

Petros Drakakis ◽

...

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Promoter Polymorphism ◽

European Population ◽

Pcr Analysis ◽

Control Group ◽

Necrosis Factor Alpha ◽

Healthy Women ◽

Tnf Α ◽

Necrosis Factor

Abstract Background Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine which plays an important role in the pathogenesis of many diseases. Endometriosis is one of the most common gynecological diseases. The purpose of this study was to investigate the association of TNF-α-1031T/C polymorphism with the genetic susceptibility of endometriosis in a European population. Materials and methods In this case-control study, 51 endometriosis patients and 67 healthy control women participated. We used endometrial tissue from the patients and peripheral blood from the healthy women to extract DNA. Polymerase chain reaction (PCR) analysis and the restriction enzyme Bbs I were used to analyze the -1031 T/C polymorphism in the TNF-α gene promoter region. Statistical analysis was performed using Fisher’s exact test. We also calculated the odds ratios. Results In the group of patients, 66.7% of women were detected with the TT genotype, 33.3% with the TC genotype and 0% with the CC genotype while in the control group, 46.3% had the TT genotype, 47.8% had the TC genotype and 6% had the CC genotype. There was a significant association between the TT genotype with endometriosis (p = 0.03). There was no significant deviation from the Hardy-Weinberg equilibrium. Conclusions The TC and CC genotypes appeared more often in the healthy women than the endometriosis patients and this shows that the C allele might have a protective role in endometriosis in the Greek population. Further studies are needed to specify the role of this polymorphism in pathogenesis of endometriosis and the mechanisms that protect the patients from the disease.

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Piquiá Shells (Caryocar villosum): A Fruit by-Product with Antioxidant and Antiaging Properties in Caenorhabditis elegans

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/7590707 ◽

2020 ◽

Vol 2020 ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

Mariana Roxo ◽

Herbenya Peixoto ◽

Pille Wetterauer ◽

Emerson Lima ◽

Michael Wink

Keyword(s):

Caenorhabditis Elegans ◽

Lethal Dose ◽

Pcr Analysis ◽

Transcriptional Level ◽

Dependent Manner ◽

Wild Type ◽

Fluorescent Reporter ◽

Triterpenoid Saponins ◽

Promising Source

In a context of rising demand for sustainable antiaging interventions, fruit processing by-products are a promising source of bioactive compounds for the production of antiaging dietary supplements. Piquiá (Caryocar villosum) is a native Amazonian fruit consisting of 65% nonedible shells. In the present study, the phytochemical profile of a hydroalcoholic extract of piquiá shells (CV) was characterized by LC-MS/MS analysis. Its antioxidant and antiaging activities were investigated using the nematode Caenorhabditis elegans as an in vivo model. CV is mainly composed by hydrolysable tannins and triterpenoid saponins. The extract enhanced stress resistance of wild-type and mutant worms by reducing the intracellular levels of reactive oxygen species (ROS) and by increasing their survival against a lethal dose of the prooxidant juglone. These effects involved the upregulation of sod-3 and downregulation of gst-4 and hsp-16.2, studied through the GFP fluorescent reporter intensity and at the transcriptional level by qRT-PCR analysis. CV extended the lifespan of wild-type worms in a DAF-16/FoxO- and SKN-1/Nrf-dependent manner. Taken together, our findings indicate piquiá shells as potential candidates for nutraceutical applications. Further studies are needed to validate the relevance of our findings to antiaging interventions in humans.

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Involvement of TNF-α and IFN-γ in Inflammation-Mediated Cochlear Injury

Annals of Otology Rhinology & Laryngology ◽

10.1177/0003489419837689 ◽

2019 ◽

Vol 128 (6_suppl) ◽

pp. 8S-15S ◽

Cited By ~ 3

Author(s):

Sung K. Moon ◽

Jeong-Im Woo ◽

David J. Lim

Keyword(s):

Cell Injury ◽

Ex Vivo ◽

Organ Of Corti ◽

Blue Staining ◽

Sensory Cells ◽

Spiral Ligament ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Ifn Γ ◽

High Concentrations

Objectives: Inflammation is crucial for the pathogenesis of acquired sensorineural hearing loss, but the precise mechanism involved remains elusive. Among a number of inflammatory mediators, tumor necrosis factor-alpha (TNF-α) plays a pivotal role in cisplatin ototoxicity. However, TNF-α alone is cytotoxic to cochlear sensory cells only at the extremely high concentrations, suggesting the involvement of other factors that may sensitize cells to TNF-α cytotoxicity. Since interferon gamma (IFN-γ) importantly contributes to the cochlear inflammatory processes, we aim to determine whether and how IFN-γ affects TNF-α cytotoxicity to cochlear sensory cells. Methods: TNF-α expression was determined with western blotting in RSL cells and immunolabeling of mouse temporal bone sections. HEI-OC1 cell viability was determined with MTT assays, cytotoxicity assays, and cytometric analysis with methylene blue staining. Cochlear sensory cell injury was determined in the organotypic culture of the mouse organ of Corti. Results: Spiral ligament fibrocytes were shown to upregulate TNF-α in response to pro-inflammatory stimulants. We demonstrated IFN-γ increases the susceptibility of HEI-OC1 cells to TNF-α cytotoxicity via JAK1/2-STAT1 signaling. TNFR1-mediated Caspase-1 activation was found to mediate the sensitization effect of IFN-γ on TNF-α cytotoxicity. The combination of IFN-γ and TNF-α appeared to augment cisplatin cytotoxicity to cochlear sensory cells ex vivo. Conclusions: Taken together, these findings suggest the involvement of IFN-γ in the sensitization of cochlear cells to TNF-α cytotoxicity, which would enable us to better understand the complex mechanisms underlying inflammation-mediated cochlear injury.

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