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Huang EY, Peng CT, Wang CC. Effects of radiation response modifiers given after lethal whole-abdominal irradiation. Int J Radiat Biol 2018; 94:289-294. [PMID: 29355463 DOI: 10.1080/09553002.2018.1431698] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
PURPOSE Although radiation is used to treat cancer and generate electricity, radiotherapy-induced complications and nuclear disasters are issues of great concern. The small bowel and bone marrow are the two major organs injured by radiation, especially that from nuclear disasters. The development of effective drugs to alleviate radiation injuries is very important. We tested potential radiation response modifiers given after irradiation to alleviate radiation injuries and mortality. MATERIALS AND METHODS Xenografts of C33A tumor cells with or without galectin-1 expression were implanted in SCID mice. Local tumor irradiation (6 Gy) was used to study radiosensitivity. The rate and time of tumor growth to 2 cm were observed using the Kaplan-Meier method. C57BL/6N mice were used to study the effects of whole-abdominal or whole-body irradiation. Drug administration was as follows: (1) vehicle; (2) interleukin 6 (IL-6) (50 ng/day); (3) anginex (10 mg/kg/day) (galectin-1 antagonist); or (4) flagellin (0.2 mg/kg) (Toll-like receptor 5 agonist). These treatments were compared for tumor size and survival time. RESULTS The median time of tumor growth delay after 6 Gy irradiation was one week in tumors without galectin-1 expression, regardless of anginex administration. Anginex did not prolong the survival time after 18 Gy whole-abdominal irradiation. Flagellin did not prolong survival time after 18 Gy whole-abdominal irradiation. IL-6 prolonged the survival time after 18 Gy whole-abdominal irradiation, with 5% survival. This was the best result in treating lethal 18 Gy whole-abdominal irradiation. Other than IL-6, no drugs decreased the survival rate after 7.5 Gy whole-body irradiation. CONCLUSIONS Anginex has no protective effects against radiation injury and no radiosensitized effects on tumors. IL-6 is a potential agent for treating radiation-induced lethal injuries to the small bowel. However, it is not suitable for treating bone marrow damage after whole-body irradiation.
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Affiliation(s)
- Eng-Yen Huang
- a Department of Radiation Oncology , Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine , Kaohsiung , Taiwan.,b School of Traditional Chinese Medicine , Chang Gung University College of Medicine , Taoyuan , Taiwan
| | - Chen-Tzu Peng
- a Department of Radiation Oncology , Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine , Kaohsiung , Taiwan
| | - Chung-Chih Wang
- a Department of Radiation Oncology , Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine , Kaohsiung , Taiwan
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Hancz D, Szabo A, Molnar T, Varga Z, Hancz A, Gregus A, Hueber AO, Rajnavolgyi E, Koncz G. Flagellin increases death receptor-mediated cell death in a RIP1-dependent manner. Immunol Lett 2018; 193:42-50. [DOI: 10.1016/j.imlet.2017.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/18/2017] [Accepted: 11/20/2017] [Indexed: 12/26/2022]
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Chan PL, Zheng J, Liu Y, Lam KT, Xiang Z, Mao H, Liu Y, Qin G, Lau YL, Tu W. TLR5 signaling enhances the proliferation of human allogeneic CD40-activated B cell induced CD4hiCD25+ regulatory T cells. PLoS One 2013; 8:e67969. [PMID: 23844139 PMCID: PMC3700901 DOI: 10.1371/journal.pone.0067969] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 05/23/2013] [Indexed: 01/07/2023] Open
Abstract
Although diverse functions of different toll-like receptors (TLR) on human natural regulatory T cells have been demonstrated recently, the role of TLR-related signals on human induced regulatory T cells remain elusive. Previously our group developed an ex vivo high-efficient system in generating human alloantigen-specific CD4hiCD25+ regulatory T cells from naïve CD4+CD25− T cells using allogeneic CD40-activated B cells as stimulators. In this study, we investigated the role of TLR5-related signals on the generation and function of these novel CD4hiCD25+ regulatory T cells. It was found that induced CD4hiCD25+ regulatory T cells expressed an up-regulated level of TLR5 compared to their precursors. The blockade of TLR5 using anti-TLR5 antibodies during the co-culture decreased CD4hiCD25+ regulatory T cells proliferation by induction of S phase arrest. The S phase arrest was associated with reduced ERK1/2 phosphorylation. However, TLR5 blockade did not decrease the CTLA-4, GITR and FOXP3 expressions, and the suppressive function of CD4hiCD25+ regulatory T cells. In conclusion, we discovered a novel function of TLR5-related signaling in enhancing the proliferation of CD4hiCD25+ regulatory T cells by promoting S phase progress but not involved in the suppressive function of human CD40-activated B cell-induced CD4hiCD25+ regulatory T cells, suggesting a novel role of TLR5-related signals in the generation of induced regulatory T cells.
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Affiliation(s)
- Ping-Lung Chan
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Jian Zheng
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Yinping Liu
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Kwok-Tai Lam
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Zheng Xiang
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Huawei Mao
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Yuan Liu
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Gang Qin
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Yu-Lung Lau
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
| | - Wenwei Tu
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong. Hong Kong SAR, China
- * E-mail:
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Detection of flagellin by interaction with human recombinant TLR5 immobilized in liposomes. Anal Bioanal Chem 2012. [DOI: 10.1007/s00216-012-6523-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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de Zoete MR, Keestra AM, Wagenaar JA, van Putten JPM. Reconstitution of a functional Toll-like receptor 5 binding site in Campylobacter jejuni flagellin. J Biol Chem 2010; 285:12149-58. [PMID: 20164175 PMCID: PMC2852954 DOI: 10.1074/jbc.m109.070227] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 01/21/2010] [Indexed: 11/06/2022] Open
Abstract
Bacterial flagellin is important for intestinal immune homeostasis. Flagellins from most species activate Toll-like receptor 5 (TLR5). The principal bacterial food-borne pathogen Campylobacter jejuni escapes TLR5 recognition, probably due to an alternate flagellin subunit structure. We investigated the molecular basis of TLR5 evasion by aiming to reconstitute TLR5 stimulating activity in live C. jejuni. Both native glycosylated C. jejuni flagellins (FlaA and FlaB) and recombinant proteins purified from Escherichia coli failed to activate NF-kappaB in HEK293 cells expressing TLR5. Introduction of multiple defined regions from Salmonella flagellin into C. jejuni FlaA via a recombinatorial approach revealed three regions critical for the activation of human and mouse TLR5, including a beta-hairpin structure not previously implicated in TLR5 recognition. Surprisingly, this domain was not required for the activation of chicken TLR5, indicating a selective requirement for the beta-hairpin in the recognition of mammalian TLR5. Expression of the active chimeric protein in C. jejuni resulted in secreted glycosylated flagellin that induced a potent TLR5 response. Overall, our results reveal a novel structural requirement for TLR5 recognition of bacterial flagellin and exclude flagellin glycosylation as an additional mechanism of bacterial evasion of the TLR5 response.
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Affiliation(s)
- Marcel R. de Zoete
- From the Department of Infectious Diseases and Immunology, Utrecht University, P. O. Box 80.165, 3508 TD Utrecht, The Netherlands and
| | - A. Marijke Keestra
- From the Department of Infectious Diseases and Immunology, Utrecht University, P. O. Box 80.165, 3508 TD Utrecht, The Netherlands and
| | - Jaap A. Wagenaar
- From the Department of Infectious Diseases and Immunology, Utrecht University, P. O. Box 80.165, 3508 TD Utrecht, The Netherlands and
- the WHO Collaborating Centre for Campylobacter/OIE Reference Laboratory for Campylobacteriosis Utrecht/Lelystad, P.O. Box 65, 8200 AB Lelystad, The Netherlands Lelystad, The Netherlands
| | - Jos P. M. van Putten
- From the Department of Infectious Diseases and Immunology, Utrecht University, P. O. Box 80.165, 3508 TD Utrecht, The Netherlands and
- the WHO Collaborating Centre for Campylobacter/OIE Reference Laboratory for Campylobacteriosis Utrecht/Lelystad, P.O. Box 65, 8200 AB Lelystad, The Netherlands Lelystad, The Netherlands
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Molecular modulation of intestinal epithelial barrier: contribution of microbiota. J Biomed Biotechnol 2010; 2010:305879. [PMID: 20150966 PMCID: PMC2817557 DOI: 10.1155/2010/305879] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Accepted: 10/28/2009] [Indexed: 12/16/2022] Open
Abstract
The daunting task required of the gut-barrier to prevent luminal pathogens and harmful substances from entering into the internal milieu and yet promoting digestion and absorption of nutrients requires an exquisite degree of coordination between the different architectural units of this barrier. The complex integration and execution of these functions are superbly carried out by the intestinal mucosal (IM) surface. Exposed to trillions of luminal microbes, the IM averts threats by signaling to the innate immune system, through pattern recognition receptors (PRR), to respond to the commensal bacteria by developing tolerance (hyporesponsiveness) towards them. This system also acts by protecting against pathogens by elaborating and releasing protective peptides, cytokines, chemokines, and phagocytic cells. The IM is constantly sampling luminal contents and making molecular adjustments at its frontier. This article describes the topography of the IM and the mechanisms of molecular adjustments that protect the internal milieu, and also describes the role of the microbiota in achieving this goal.
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Abstract
Soon after birth, the neonatal intestine is confronted with a massive antigenic challenge of microbial colonization. Microbial signals are required for maturation of several physiological, anatomical, and biochemical functions of intestinal epithelial barrier (IEB) after birth. Commensal bacteria regulate intestinal innate and adaptive immunity and provide stimuli for ongoing repair and restitution of IEB. Colonization by pathogenic bacteria and/or dysmature response to microbial stimuli can result in flagrant inflammatory response as seen in necrotizing enterocolitis (NEC). Characterized by inflammation and hemorrhagic-ischemic necrosis, NEC is a devastating complication of prematurity. Although there is evidence that both prematurity and presence of bacteria, are proven contributing factors to the pathogenesis of NEC, the molecular mechanisms involved in IEB dysfunction associated with NEC have begun to emerge only recently. The metagenomic advances in the field of intestinal microecology are providing insight into the factors that are required for establishment of commensal bacteria that appear to provide protection against intestinal inflammation and NEC. Perturbations in achieving colonization by commensal bacteria such as premature birth or hospitalization in intensive care nursery can result in dysfunction of IEB and NEC. In this article, microbial modulation of functions of IEB and its relationship with barrier dysfunction and NEC are described.
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Affiliation(s)
- Renu Sharma
- Division of Neonatology, Department of Pediatrics, University of Florida at Jacksonville, 655 West 8th Street, Jacksonville, FL 32209, USA.
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Jayakumar D, Jacobs WR, Narayanan S. Protein kinase E of Mycobacterium tuberculosis has a role in the nitric oxide stress response and apoptosis in a human macrophage model of infection. Cell Microbiol 2007; 10:365-74. [PMID: 17892498 DOI: 10.1111/j.1462-5822.2007.01049.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mycobacterium tuberculosis, an intracellular pathogen, inhibits macrophage apoptosis to support survival and replication inside the host cell. We provide evidence that the functional serine/threonine kinase, PknE, is important for survival of M. tuberculosis that enhances macrophage viability by inhibiting apoptosis. A promoter of PknE identified in this study was shown to respond to nitric oxide stress. Deletion of pknE in virulent M. tuberculosis, H37Rv, resulted in a strain that has increased resistance to nitric oxide donors and increased sensitivity to reducing agents. The deletion mutant created by specialized transduction induced enhanced apoptosis while inhibiting necrosis. The pknE mutant also modifies the innate immune response as shown by the marked decline in the pro-inflammatory cytokines in a macrophage model of infection. These findings suggest a novel mechanism, by which PknE senses nitric oxide stress and prevents apoptosis by interfering with host signalling pathways.
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Affiliation(s)
- Deepak Jayakumar
- Department of Immunology, Tuberculosis Research Centre (ICMR), Chetput, Chennai-600031, India
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Rawls JF, Mahowald MA, Goodman AL, Trent CM, Gordon JI. In vivo imaging and genetic analysis link bacterial motility and symbiosis in the zebrafish gut. Proc Natl Acad Sci U S A 2007; 104:7622-7. [PMID: 17456593 PMCID: PMC1855277 DOI: 10.1073/pnas.0702386104] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Indexed: 01/01/2023] Open
Abstract
Complex microbial communities reside within the intestines of humans and other vertebrates. Remarkably little is known about how these microbial consortia are established in various locations within the gut, how members of these consortia behave within their dynamic ecosystems, or what microbial factors mediate mutually beneficial host-microbial interactions. Using a gnotobiotic zebrafish-Pseudomonas aeruginosa model, we show that the transparency of this vertebrate species, coupled with methods for raising these animals under germ-free conditions can be used to monitor microbial movement and localization within the intestine in vivo and in real time. Germ-free zebrafish colonized with isogenic P. aeruginosa strains containing deletions of genes related to motility and pathogenesis revealed that loss of flagellar function results in attenuation of evolutionarily conserved host innate immune responses but not conserved nutrient responses. These results demonstrate the utility of gnotobiotic zebrafish in defining the behavior and localization of bacteria within the living vertebrate gut, identifying bacterial genes that affect these processes, and assessing the impact of these genes on host-microbial interactions.
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Affiliation(s)
- John F. Rawls
- *Center for Genome Sciences, Washington University School of Medicine, St. Louis, MO 63108; and
- Department of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, NC 27599
| | - Michael A. Mahowald
- *Center for Genome Sciences, Washington University School of Medicine, St. Louis, MO 63108; and
| | - Andrew L. Goodman
- *Center for Genome Sciences, Washington University School of Medicine, St. Louis, MO 63108; and
| | - Chad M. Trent
- Department of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, NC 27599
| | - Jeffrey I. Gordon
- *Center for Genome Sciences, Washington University School of Medicine, St. Louis, MO 63108; and
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Gewirtz AT. TLRs in the Gut. III. Immune responses to flagellin in Crohn's disease: good, bad, or irrelevant? Am J Physiol Gastrointest Liver Physiol 2007; 292:G706-10. [PMID: 17038626 DOI: 10.1152/ajpgi.00347.2006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Recent observations suggest that bacterial flagellin may be a target of the seemingly aberrant innate and adaptive immune responses that are associated with Crohn's disease. This article discusses the evidence that supports a role for flagellin in Crohn's disease and considers the potential roles of these responses in the pathophysiology of this disorder.
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Affiliation(s)
- Andrew T Gewirtz
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia, GA 30322, USA.
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