Gnotobiotic IL-10; NF-kappaB mice develop rapid and severe colitis following Campylobacter jejuni infection.
Limited information is available on the molecular mechanisms associated with Campylobacter jejuni (C. jejuni) induced food-borne diarrheal illnesses. In this study, we investigated the function of TLR/NF-kappaB signaling in C. jejuni induced pathogenesis using gnotobiotic IL-10(-/-); NF-kappaB(EGFP) mice. In vitro analysis showed that C. jejuni induced IkappaB phosphorylation, followed by enhanced NF-kappaB transcriptional activity and increased IL-6, MIP-2alpha and NOD2 mRNA accumulation in infected-mouse colonic epithelial cells CMT93. Importantly, these events were blocked by molecular delivery of an IkappaB inhibitor (Ad5IkappaBAA). NF-kappaB signalling was also important for C.jejuni-induced cytokine gene expression in bone marrow-derived dendritic cells. Importantly, C. jejuni associated IL-10(-/-); NF-kappaB(EGFP) mice developed mild (day 5) and severe (day 14) ulcerating colonic inflammation and bloody diarrhea as assessed by colonoscopy and histological analysis. Macroscopic analysis showed elevated EGFP expression indicating NF-kappaB activation throughout the colon of C. jejuni associated IL-10(-/-); NF-kappaB(EGFP) mice, while fluorescence microscopy revealed EGFP positive cells to be exclusively located in lamina propria mononuclear cells. Pharmacological NF-kappaB inhibition using Bay 11-7085 did not ameliorate C. jejuni induced colonic inflammation. Our findings indicate that C. jejuni induces rapid and severe intestinal inflammation in a susceptible host that correlates with enhanced NF-kappaB activity from lamina propria immune cells.
Department of Medicine and Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
Elisabeth
E
Lippert
Thomas
T
Karrasch
Xiaolun
X
Sun
Brigitte
B
Allard
Hans H
HH
Herfarth
Deborah
D
Threadgill
Christian
C
Jobin
D000818:Animals; D001854:Bone Marrow Cells / Q000378:metabolism; D002169:Campylobacter Infections / Q000382:microbiology*; D016123:Campylobacter jejuni / Q000378:metabolism*; D054426:Chemokine CXCL2 / Q000096:biosynthesis; D003092:Colitis / Q000235:genetics* / Q000378:metabolism* / Q000382:microbiology*; D003713:Dendritic Cells / Q000166:cytology; D005786:Gene Expression Regulation; D005856:Germ-Free Life / Q000235:genetics*; D020672:I-kappa B Proteins / Q000378:metabolism; D016753:Interleukin-10 / Q000235:genetics* / Q000502:physiology; D015850:Interleukin-6 / Q000378:metabolism; D051379:Mice; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000235:genetics* / Q000502:physiology; D053473:Nod2 Signaling Adaptor Protein / Q000378:metabolism; D010766:Phosphorylation
D054426:Chemokine CXCL2; D020672:I-kappa B Proteins; D015850:Interleukin-6; D016328:NF-kappa B; C000606205:Nfkbia protein, mouse; D053473:Nod2 Signaling Adaptor Protein; C495945:Nod2 protein, mouse; D016753:Interleukin-10; D000072000:NF-KappaB Inhibitor alpha