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Cited by 75Inflammatory Bowel DiseaseParasites and Host InteractionsIL-33, ST2, and ILC Pathways

Therapeutic potential of recombinant cystatin from Schistosoma japonicum in TNBS-induced experimental colitis of mice

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Wang, Shushu, Xie, Yuanyuan, Yang, Xiaodi, Wang, Xuesong, Yan, Ke, Zhong, Zhengrong, Wang, Xiaowei, Xu, Yuanhong +3 more·2016·Parasites & Vectors
DOI 10.1186/s13071-015-1288-1PMC PMC4700642
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Abstract

BACKGROUND: Helminth infections and their components have been shown to have a protective effect on autoimmune diseases. The isolated purified protein from Schisotosoma japonicum and its potential therapeutic effect on trinitrobenzene sulfonic acid (TNBS)-induced colitis could provide an alternative way to treat inflammatory bowel disease (IBDs). METHODS: Colitis was induced in Balb/c mice by rectal administration of 2.5% TNBS, followed by intraperitoneal injection of rSjcystatin 50 μg at 6 h and 24 h afterwards. The inflammation was monitored by recording weight change, stool character and bleeding, colon length, macroscopic score (MAO), microscopic score (MIO), myeloperoxidase activity (MPO) and disease activity index (DAI). The potential underlying mechanism was investigated by examining cytokine profiles including Th1 (IFNγ), Th2 (IL-4), Th17 (IL-17A) and Treg subsets from lymphocytes of spleen, mesenteric lymph nodes (MLN) and intestinal lamina propria mononuclear cells (LPMCs) by flow cytometry. The mRNA relative expressions of the cytokines in splenocytes and MLN were analysed by quantitative real time reverse-transcriptase polymerase chain reaction (qRT-PCR). Simultaneously, the concentrations of the cytokines in the colon homogenate supernatants were tested by enzyme-linked immunosorbent assay (ELISA) and key transcription factors were detected by Western blotting. RESULTS: Administration of rSjcystatin significantly reduced inflammatory parameters and ameliorated the severity of the TNBS-induced colitis through decreasing IFNγ in three organs and lifting the level of IL-4, IL-13, IL-10, and TGF-β in the colon tissues, with uptrending Tregs in the MLN and LPMC. CONCLUSION: The findings provide evidence that rSjcystatin has a therapeutic potential for diminishing colitis inflammation in Balb/c mice. The immunological mechanism may involve the down-regulation of Th1 response and up-regulation of Th2 and Tregs in the MLN and colon.

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  • Helminth cystatins from S. japonicum, Ascaris lumbricoides, and Clonorchis sinensis all ameliorate colitis in vivo.

    “Other helminth cystatins with broad immunomodulatory properties including those from S. japonicum (Wang et al., 2016), Ascaris lumbricoides, and the liver fluke Clonorchis sinensis all ameliorate colitis in vivo”

    From Modulation of Host Immunity by Helminths: The Expanding Repertoire of Parasite Effector Molecules (2018) · cites this paper as Wang et al., 2016

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  1. [1]Bager P Simonsen J Nielsen NM Frisch M Cesarean section and offspring's risk of inflammatory bowel disease: a national cohort study Inflamm Bowel Dis 2012 18 5 857 862 10.1002/ibd.21805 21739532 · DOI
  2. [2]De Filippo C Cavalieri D Di Paola M Ramazzotti M Poullet JB Massart S Impact of diet in shaping gut microbiota revealed by a comparative study in children from Europe and rural Africa Proc Natl Acad Sci U S A 2010 107 33 14691 14696 10.1073/pnas.1005963107 20679230 PMC2930426 · DOI · Paper page
  3. [3]Hviid A Svanstrom H Frisch M Antibiotic use and inflammatory bowel diseases in childhood Gut 2011 60 1 49 54 10.1136/gut.2010.219683 20966024 · DOI
  4. [4]Fiocchi C One commensal bacterial molecule--all we need for health? N Engl J Med 2005 353 19 2078 2080 10.1056/NEJMcibr053171 16282185 · DOI
  5. [5]Kozuch PL Hanauer SB Treatment of inflammatory bowel disease: a review of medical therapy World J Gastroenterol 2008 14 3 354 377 10.3748/wjg.14.354 18200659 PMC2679125 · DOI
  6. [6]Bamias G Cominelli F Novel strategies to attenuate immune activation in Crohn's disease Curr Opin Pharmacol 2006 6 4 401 407 10.1016/j.coph.2006.03.008 16753341 · DOI
  7. [7]Molodecky NA Soon IS Rabi DM Ghali WA Ferris M Chernoff G Increasing incidence and prevalence of the inflammatory bowel diseases with time, based on systematic review Gastroenterology 2012 142 1 46 54 10.1053/j.gastro.2011.10.001 22001864 · DOI · Paper page
  8. [8]Shin DH Sinn DH Kim YH Kim JY Chang DK Kim EJ Increasing incidence of inflammatory bowel disease among young men in Korea between 2003 and 2008 Dig Dis Sci 2011 56 4 1154 1159 10.1007/s10620-010-1403-2 20844953 · DOI
  9. [9]Wang YF Ouyang Q Hu RW Progression of inflammatory bowel disease in China J Dig Dis 2010 11 2 76 82 10.1111/j.1751-2980.2010.00421.x 20402832 · DOI
  10. [10]Buning J Homann N von Smolinski D Borcherding F Noack F Stolte M Helminths as governors of inflammatory bowel disease Gut 2008 57 8 1182 1183 10.1136/gut.2008.152355 18628388 · DOI
  11. [11]Broadhurst MJ Leung JM Kashyap V McCune JM Mahadevan U McKerrow JH IL-22+ CD4+ T cells are associated with therapeutic trichuris trichiura infection in an ulcerative colitis patient Sci Transl Med 2010 2 60 60ra88 21123809
  12. [12]Kabeerdoss J Pugazhendhi S Subramanian V Binder HJ Ramakrishna BS Exposure to hookworms in patients with Crohn's disease: a case–control study Aliment Pharmacol Ther 2011 34 8 923 930 10.1111/j.1365-2036.2011.04824.x 21848628 · DOI
  13. [13]Setiawan T Metwali A Blum AM Ince MN Urban JF Jr Elliott DE Heligmosomoides polygyrus promotes regulatory T-cell cytokine production in the murine normal distal intestine Infect Immun 2007 75 9 4655 4663 10.1128/IAI.00358-07 17606601 PMC1951154 · DOI
  14. [14]Sutton TL Zhao A Madden KB Elfrey JE Tuft BA Sullivan CA Anti-Inflammatory mechanisms of enteric Heligmosomoides polygyrus infection against trinitrobenzene sulfonic acid-induced colitis in a murine model Infect Immun 2008 76 10 4772 4782 10.1128/IAI.00744-07 18644879 PMC2546858 · DOI
  15. [15]Khan WI Blennerhasset PA Varghese AK Chowdhury SK Omsted P Deng Y Intestinal nematode infection ameliorates experimental colitis in mice Infect Immun 2002 70 11 5931 5937 10.1128/IAI.70.11.5931-5937.2002 12379667 PMC130294 · DOI
  16. [16]Motomura Y Wang H Deng Y El-Sharkawy RT Verdu EF Khan WI Helminth antigen-based strategy to ameliorate inflammation in an experimental model of colitis Clin Exp Immunol 2009 155 1 88 95 10.1111/j.1365-2249.2008.03805.x 19016806 PMC2665684 · DOI
  17. [17]Elliott DE Li J Blum A Metwali A Qadir K Urban JF Jr Exposure to schistosome eggs protects mice from TNBS-induced colitis Am J Physiol Gastrointest Liver Physiol 2003 284 3 G385 391 10.1152/ajpgi.00049.2002 12431903 · DOI
  18. [18]Kordis D Turk V Phylogenomic analysis of the cystatin superfamily in eukaryotes and prokaryotes BMC Evol Biol 2009 9 266 10.1186/1471-2148-9-266 19919722 PMC2784779 · DOI
  19. [19]Hartmann S Adam R Marti T Kirsten C Seidinger S Lucius R A 41-kDa antigen of the rodent filaria Acanthocheilonema viteae with homologies to tropomyosin induces host-protective immune responses Parasitol Res 1997 83 4 390 393 10.1007/s004360050269 9134565 · DOI
  20. [20]Hartmann S Kyewski B Sonnenburg B Lucius R A filarial cysteine protease inhibitor down-regulates T cell proliferation and enhances interleukin-10 production Eur J Immunol 1997 27 9 2253 2260 10.1002/eji.1830270920 9341767 · DOI
  21. [21]Manoury B Gregory WF Maizels RM Watts C Bm-CPI-2, a cystatin homolog secreted by the filarial parasite Brugia malayi, inhibits class II MHC-restricted antigen processing Curr Biol 2001 11 6 447 451 10.1016/S0960-9822(01)00118-X 11301256 · DOI · Paper page
  22. [23]Harnett W Secretory products of helminth parasites as immunomodulators Mol Biochem Parasitol 2014 195 2 130 136 10.1016/j.molbiopara.2014.03.007 24704440 · DOI
  23. [24]Lustigman S Brotman B Huima T Prince AM Characterization of an Onchocerca volvulus cDNA clone encoding a genus specific antigen present in infective larvae and adult worms Mol Biochem Parasitol 1991 45 1 65 75 10.1016/0166-6851(91)90028-5 2052041 · DOI
  24. [25]Lustigman S Brotman B Huima T Prince AM McKerrow JH Molecular cloning and characterization of onchocystatin, a cysteine proteinase inhibitor of Onchocerca volvulus J Biol Chem 1992 267 24 17339 17346 1512269
  25. [26]Newlands GF Skuce PJ Knox DP Smith WD Cloning and expression of cystatin, a potent cysteine protease inhibitor from the gut of Haemonchus contortus Parasitology 2001 122 Pt 3 371 378 11289073
  26. [27]Vray B Hartmann S Hoebeke J Immunomodulatory properties of cystatins Cell Mol Life Sci 2002 59 9 1503 1512 10.1007/s00018-002-8525-4 12440772 PMC11337455 · DOI
  27. [28]Morales FC Furtado DR Rumjanek FD The N-terminus moiety of the cystatin SmCys from Schistosoma mansoni regulates its inhibitory activity in vitro and in vivo Mol Biochem Parasitol 2004 134 1 65 73 10.1016/j.molbiopara.2003.10.016 14747144 · DOI
  28. [29]He B Cai G Ni Y Li Y Zong H He L Characterization and expression of a novel cystatin gene from Schistosoma japonicum Mol Cell Probes 2011 25 4 186 193 10.1016/j.mcp.2011.05.001 21601634 · DOI
  29. [30]Yang X Liu J Yue Y Chen W Song M Zhan X Cloning, expression and characterisation of a type II cystatin from Schistosoma japonicum, which could regulate macrophage activation Parasitol Res 2014 113 11 3985 3992 10.1007/s00436-014-4064-9 25096535 · DOI
  30. [31]Alex P Zachos NC Nguyen T Gonzales L Chen TE Conklin LS Distinct cytokine patterns identified from multiplex profiles of murine DSS and TNBS-induced colitis Inflamm Bowel Dis 2009 15 3 341 352 10.1002/ibd.20753 18942757 PMC2643312 · DOI
  31. [32]Menachem Y Trop S Kolker O Shibolet O Alper R Nagler A Adoptive transfer of NK 1.1+ lymphocytes in immune-mediated colitis: a pro-inflammatory or a tolerizing subgroup of cells? Microbes and infection / Institut Pasteur 2005 7 5–6 825 835 10.1016/j.micinf.2005.03.019 15893498 · DOI
  32. [33]Axelsson LG Landstrom E Bylund-Fellenius AC Experimental colitis induced by dextran sulphate sodium in mice: beneficial effects of sulphasalazine and olsalazine Aliment Pharmacol Ther 1998 12 9 925 934 10.1046/j.1365-2036.1998.00357.x 9768537 · DOI
  33. [34]Obermeier F Kojouharoff G Hans W Scholmerich J Gross V Falk W Interferon-gamma (IFN-gamma)- and tumour necrosis factor (TNF)-induced nitric oxide as toxic effector molecule in chronic dextran sulphate sodium (DSS)-induced colitis in mice Clin Exp Immunol 1999 116 2 238 245 10.1046/j.1365-2249.1999.00878.x 10337013 PMC1905281 · DOI
  34. [35]Ruyssers NE De Winter BY De Man JG Loukas A Pearson MS Weinstock JV Therapeutic potential of helminth soluble proteins in TNBS-induced colitis in mice Inflamm Bowel Dis 2009 15 4 491 500 10.1002/ibd.20787 19023900 · DOI
  35. [36]Heylen M Ruyssers NE De Man JG Timmermans JP Pelckmans PA Moreels TG Worm proteins of Schistosoma mansoni reduce the severity of experimental chronic colitis in mice by suppressing colonic proinflammatory immune responses PLoS One 2014 9 10 10.1371/journal.pone.0110002 25313594 PMC4196959 · DOI
  36. [37]Yang X Yang Y Wang Y Zhan B Gu Y Cheng Y Excretory/secretory products from Trichinella spiralis adult worms ameliorate DSS-induced colitis in mice PLoS One 2014 9 5 10.1371/journal.pone.0096454 24788117 PMC4008629 · DOI
  37. [38]Leung J Hang L Blum A Setiawan T Stoyanoff K Weinstock J Heligmosomoides polygyrus abrogates antigen-specific gut injury in a murine model of inflammatory bowel disease Inflamm Bowel Dis 2012 18 8 1447 1455 10.1002/ibd.22858 22223533 PMC4123417 · DOI
  38. [39]Ferreira I Smyth D Gaze S Aziz A Giacomin P Ruyssers N Hookworm excretory/secretory products induce interleukin-4 (IL-4) + IL-10+ CD4+ T cell responses and suppress pathology in a mouse model of colitis Infect Immun 2013 81 6 2104 2111 10.1128/IAI.00563-12 23545299 PMC3676036 · DOI
  39. [40]Honey K Rudensky AY Lysosomal cysteine proteases regulate antigen presentation Nat Rev Immunol 2003 3 6 472 482 10.1038/nri1110 12776207 · DOI
  40. [41]Turk V Turk B Turk D Lysosomal cysteine proteases: facts and opportunities EMBO J 2001 20 17 4629 4633 10.1093/emboj/20.17.4629 11532926 PMC125585 · DOI
  41. [42]Kos J Lah TT Cysteine proteinases and their endogenous inhibitors: target proteins for prognosis, diagnosis and therapy in cancer (review) Oncol Rep 1998 5 6 1349 1361 9769367
  42. [43]Lang A Horler D Baici A The relative importance of cysteine peptidases in osteoarthritis J Rheumatol 2000 27 8 1970 1979 10955340
  43. [44]Nixon RA Cataldo AM Mathews PM The endosomal-lysosomal system of neurons in Alzheimer's disease pathogenesis: a review Neurochem Res 2000 25 9–10 1161 1172 10.1023/A:1007675508413 11059790 · DOI
  44. [45]Schnoeller C Rausch S Pillai S Avagyan A Wittig BM Loddenkemper C A helminth immunomodulator reduces allergic and inflammatory responses by induction of IL-10-producing macrophages J Immunol 2008 180 6 4265 4272 10.4049/jimmunol.180.6.4265 18322239 · DOI
  45. [46]Elson CO Sartor RB Tennyson GS Riddell RH Experimental models of inflammatory bowel disease Gastroenterology 1995 109 4 1344 1367 10.1016/0016-5085(95)90599-5 7557106 · DOI
  46. [47]Wirtz S Neufert C Weigmann B Neurath MF Chemically induced mouse models of intestinal inflammation Nat Protoc 2007 2 3 541 546 10.1038/nprot.2007.41 17406617 · DOI · Paper page
  47. [48]Izcue A Hue S Buonocore S Arancibia-Carcamo CV Ahern PP Iwakura Y Interleukin-23 restrains regulatory T cell activity to drive T cell-dependent colitis Immunity 2008 28 4 559 570 10.1016/j.immuni.2008.02.019 18400195 PMC2292821 · DOI
  48. [50]Ogawa A Andoh A Araki Y Bamba T Fujiyama Y Neutralization of interleukin-17 aggravates dextran sulfate sodium-induced colitis in mice Clin Immunol 2004 110 1 55 62 10.1016/j.clim.2003.09.013 14962796 · DOI
  49. [51]Zhang Z Zheng M Bindas J Schwarzenberger P Kolls JK Critical role of IL-17 receptor signaling in acute TNBS-induced colitis Inflamm Bowel Dis 2006 12 5 382 388 10.1097/01.MIB.0000218764.06959.91 16670527 · DOI
  50. [52]Schramm G Haas H Th2 immune response against Schistosoma mansoni infection Microbes and infection / Institut Pasteur 2010 12 12–13 881 888 10.1016/j.micinf.2010.06.001 20542135 · DOI
  51. [54]Schramm G Falcone FH Gronow A Haisch K Mamat U Doenhoff MJ Molecular characterization of an interleukin-4-inducing factor from Schistosoma mansoni eggs J Biol Chem 2003 278 20 18384 18392 10.1074/jbc.M300497200 12624091 · DOI
  52. [55]Li J Zhuang W Cong L Shi W Xingyan C Huang F Cyclophilin A from Schistosoma japonicum promotes a Th2 response in mice Parasites &Vectors 2013 6 330 10.1186/1756-3305-6-330 24238088 PMC3843525 · DOI
  53. [56]Wilson MS Ramalingam TR Rivollier A Shenderov K Mentink-Kane MM Madala SK Colitis and intestinal inflammation in IL10−/− mice results from IL-13Ralpha2-mediated attenuation of IL-13 activity Gastroenterology 2011 140 1 254 264 10.1053/j.gastro.2010.09.047 20951137 PMC3006653 · DOI
  54. [57]Alheim M Lazdina U Milich DR Sallberg M Flow cytometric determination of cytokine production and proliferation in hepatitis B core antigen specific murine CD4 cells: lack of correlation between number of cytokine producing cells and cytokine levels in supernatant J Immunol Methods 2001 258 1–2 157 167 10.1016/S0022-1759(01)00486-0 11684133 · DOI
  55. [58]Campbell DJ Koch MA Phenotypical and functional specialization of FOXP3+ regulatory T cells Nat Rev Immunol 2011 11 2 119 130 10.1038/nri2916 21267013 PMC3289970 · DOI · Paper page
  56. [59]Izcue A Coombes JL Powrie F Regulatory lymphocytes and intestinal inflammation Annu Rev Immunol 2009 27 313 338 10.1146/annurev.immunol.021908.132657 19302043 · DOI
  57. [60]Coleman MM Finlay CM Moran B Keane J Dunne PJ Mills KH The immunoregulatory role of CD4 + FoxP3 + CD25_ regulatory T cells in lungs of mice infected with Bordetella pertussis FEMS Immunol Med Microbiol 2012 64 3 413 24 10.1111/j.1574-695X.2011.00927.x 22211712 · DOI
  58. [61]Fontenot JD Rasmussen JP Williams LM Dooley JL Farr AG Rudensky AY Regulatory T cell lineage specification by the forkhead transcription factor foxp3 Immunity 2005 22 3 329 341 10.1016/j.immuni.2005.01.016 15780990 · DOI
  59. [63]Annacker O Pimenta-Araujo R Burlen-Defranoux O Barbosa TC Cumano A Bandeira A CD25+ CD4+ T cells regulate the expansion of peripheral CD4 T cells through the production of IL-10 J Immunol 2001 166 5 3008 3018 10.4049/jimmunol.166.5.3008 11207250 · DOI
  60. [64]Hasby EA Hasby Saad MA Shohieb Z El Noby K FoxP3+ T regulatory cells and immunomodulation after Schistosoma mansoni egg antigen immunization in experimental model of inflammatory bowel disease Cell Immunol 2015 295 1 67 76 10.1016/j.cellimm.2015.02.013 25766778 · DOI
  61. [65]Radovic I Gruden-Movsesijan A Ilic N Cvetkovic J Mojsilovic S Devic M Immunomodulatory effects of Trichinella spiralis-derived excretory-secretory antigens Immunol Res 2015 61 3 312 325 10.1007/s12026-015-8626-4 25616617 · DOI
  62. [66]Marks DJ Segal AW Innate immunity in inflammatory bowel disease: a disease hypothesis J Pathol 2008 214 2 260 266 10.1002/path.2291 18161747 PMC2635948 · DOI
  63. [67]Comalada M Peppelenbosch MP Impaired innate immunity in Crohn’s disease Trends Mol Med Trends Mol Med 2006 12 9 397 399 10.1016/j.molmed.2006.07.005 16890491 · DOI
  64. [68]Jang SW Cho MK Park MK Kang SA Na BK Ahn SC Parasitic Helminth Cystatin Inhibits DSS-Induced Intestinal Inflammation Via IL-10 + F4/80+ Macrophage Recruitment Korean J Parasitol 2011 49 3 245 254 10.3347/kjp.2011.49.3.245 22072824 PMC3210841 · DOI · Paper page

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Authors
Wang, S., Xie, Y., Yang, X., Wang, X., Yan, K., Zhong, Z., Wang, X., Xu, Y., Zhang, Y., Liu, F., & Shen, J.
Affiliations
  • Anhui Medical University (CN)
  • Bengbu Medical College (CN)
  • First Affiliated Hospital of Anhui Medical University (CN)
Corresponding author
Shen, Jilong
ORCID
Venue
Parasites & Vectors
Publisher
Springer Science and Business Media LLC
Published
2016-01-04
Volume
9
Issue
1
Pages
6-6
ISSN
1756-3305 (ISSN-L)
DOI
10.1186/s13071-015-1288-1
PMC
PMC4700642
OpenAlex
W2223443081
Cited by
75
References
4
Citations by year
2026: 1 · 2025: 2 · 2024: 2 · 2023: 4 · 2022: 10 · 2021: 13 · 2020: 12 · 2019: 10 · 2018: 3 · 2017: 12 · 2016: 6
FWCI
8.35
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • Parasites & Vectors (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • National Natural Science Foundation of China (No. 81441120)
  • National Natural Science Foundation of (No. 1508085QH158)
  • The Science and Technology Development Foundation of Bengbu Medical College (No. BYKF13A03)
  • Science Foundation of Anhui Province (1308085MH124)
  • National Science Foundation of China (No 81171606)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Inflammatory Bowel Disease
  • Life Sciences › Immunology and Microbiology › Parasitology › Parasites and Host Interactions
  • Life Sciences › Immunology and Microbiology › Immunology › IL-33, ST2, and ILC Pathways
Keywords
Schistosoma japonicum, TNBS-induced colitis, experimental colitis, inflammatory bowel disease, regulatory T cells, Th1/Th2 balance, Th17 cells, cytokine expression, interferon-gamma, IL-10, TGF-beta, IL-13, mesenteric lymph nodes, lamina propria mononuclear cells
MeSH terms
Animals, Colitis, Colon, Female, Gene Expression Regulation, Inflammation, Intestinal Mucosa, Mice, Inbred BALB C, Recombinant Proteins, Schistosoma japonicum, Spleen, Trinitrobenzenesulfonic Acid, Cystatins, Cytokines, T-Lymphocytes, Regulatory

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