title: Treatment of mice with dextran sulfate sodium-induced colitis with human interleukin 10 secreted by transformed Bifidobacterium longum.
abstract: Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) the etiology of which has not yet been fully clarified. Cytokine interleukin-10 (IL-10) plays a central role in downregulating inflammatory cascade in UC and is likely a candidate for therapeutic intervention. However, its intravenous administration is costly and inconvenient. Therefore, we established a novel IL-10 delivery system by transforming a hIL-10-containing plasmid into B. longum (BL-hIL-10) and investigated its effects on 5% dextran sulfate sodium (DSS)-induced ulcerative colitis in mice and the possible underlying mechanism. Our results show that (1) hIL-10 was expressed and secreted into the culture supernatant of BL-hIL-10 after L-arabinose induction in vitro as examined by Western blot, enzyme-linked immunosorbent assay (ELISA) and RT-PCR; (2) addition of BL-hIL-10 culture supernatant had no cytotoxic effect and morphological alteration, but significantly inhibited the enhancement of proinflammatory cytokines by lipopolysaccharide (LPS) in THP-1 cells; (3) oral administration of BL-hIL-10 alleviated colitis syndrome of the model mice, attenuated colitis-activated NF-κB pathway measured by DNA-binding assay and colitis-elevated expression of proinflammatory cytokines examined with CCK cytotoxic kits, and upregulated CD4+CD25+Foxp3+ Treg in blood and mesenteric lymph nodes measured by flow cytometry. In conclusion, BL-hIL-10 as a novel oral hIL-10 delivery system has been successfully established and oral administration of BL-hIL-10 alleviated inflammatory damage of colonic tissue in the model mice by blocking the colitis-activated NF-κB pathway and upregulating CD4+CD25+Foxp3+ Treg in blood and mesenteric lymph nodes in mice.
authors.affiliation: Department of Gastroenterology, Jinan University of Medical Sciences, Shenzhen Municipal People's Hospital, Shenzhen 518020, Guangdong Province, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yao
authors.forename: Jian-Yao
authors.initials: JY
authors.lastname: Wang
authors.forename: Ming-Guang
authors.initials: MG
authors.lastname: Lai
authors.forename: Ying-Xue
authors.initials: YX
authors.lastname: Li
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Zhu
authors.forename: Rui-Yue
authors.initials: RY
authors.lastname: Shi
authors.forename: Jing
authors.initials: J
authors.lastname: Mo
authors.forename: An-Ying
authors.initials: AY
authors.lastname: Xun
authors.forename: Chun-Hong
authors.initials: CH
authors.lastname: Jia
authors.forename: Ju-Ling
authors.initials: JL
authors.lastname: Feng
authors.forename: Li-Sheng
authors.initials: LS
authors.lastname: Wang
authors.forename: Wei-Sen
authors.initials: WS
authors.lastname: Zeng
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001644:Bifidobacterium / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D016264:Dextran Sulfate / Q000633:toxicity*; D004337:Drug Carriers; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D016753:Interleukin-10 / Q000008:administration & dosage* / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism
chemical_list: D016207:Cytokines; D004337:Drug Carriers; D008070:Lipopolysaccharides; D016328:NF-kappa B; D012333:RNA, Messenger; D016753:Interleukin-10; D016264:Dextran Sulfate; D009195:Peroxidase