Autoimmunity Links Vinculin to the Pathophysiology of Chronic Functional Bowel Changes Following Campylobacter jejuni Infection in a Rat Model
- 1.7k Downloads
Acute gastroenteritis can precipitate irritable bowel syndrome (IBS) in humans. Cytolethal distending toxin is common to all pathogens causing gastroenteritis. Its active subunit, CdtB, is associated with post-infectious bowel changes in a rat model of Campylobacter jejuni infection, including small intestinal bacterial overgrowth (SIBO).
To evaluate the role of host antibodies to CdtB in contributing to post-infectious functional sequelae in this rat model.
Ileal tissues from non-IBS human subjects, C. jejuni-infected and control rats were immunostained with antibodies to CdtB, c-Kit, S-100, PGP 9.5 and vinculin. Cytosolic and membrane proteins from mouse enteric neuronal cell lysates were immunoprecipitated with anti-CdtB and analyzed by mass spectrometry. ELISAs were performed on rat cardiac serum using CdtB or vinculin as antigens.
Anti-CdtB antibodies bound to a cytosolic protein in interstitial cells of Cajal (ICC) and myenteric ganglia in C. jejuni-infected and naïve rats and human subjects. Mass spectrometry identified vinculin, confirmed by co-localization and ELISAs. Anti-CdtB antibodies were higher in C. jejuni-infected rats (1.27 ± 0.15) than controls (1.76 ± 0.12) (P < 0.05), and rats that developed SIBO (2.01 ± 0.18) vs. rats that did not (1.44 ± 0.11) (P = 0.019). Vinculin expression levels were reduced in C. jejuni-infected rats (0.058 ± 0.053) versus controls (0.087 ± 0.023) (P = 0.0001), with greater reductions in rats with two C. jejuni infections (P = 0.0001) and rats that developed SIBO (P = 0.001).
Host anti-CdtB antibodies cross-react with vinculin in ICC and myenteric ganglia, required for normal gut motility. Circulating antibody levels and loss of vinculin expression correlate with number of C. jejuni exposures and SIBO, suggesting that effects on vinculin are important in the effects of C. jejuni infection on the host gut.
KeywordsIrritable bowel syndrome Cytolethal distending toxin Vinculin Small intestinal bacterial overgrowth
The antibody to the near-full-length CdtB protein used in this study was provided by Dr. Patricia Guerry (Naval Medical Research Center, Silver Spring, MD), and the recombinant CdtB protein used in this study was provided by Dr. Kenneth Bradley, MIMG Department, UCLA. This work was supported by grants from the Beatrice and Samuel A. Seaver Foundation (MP), the Shoolman Foundation (MP) and the Hansch Family Fund (MP), and by RO1 DK080684 (SS) and a VA-MERIT award (SS).
Conflict of interest
Mark Pimentel has received grants from and is a consultant for Salix Pharmaceuticals and Commonwealth Laboratories, with whom Cedars-Sinai has licensing agreements. The remaining authors have no conflicts to disclose.
- 2.Lovell RM, Ford AC. Global prevalence of and risk factors for irritable bowel syndrome: a meta-analysis. Clin Gastroenterol Hepatol Off Clin Pract J Am Gastroenterol Assoc. 2012;10:712 e714–721 e714.Google Scholar
- 3.Lembo A. The clinical and economic burden of irritable bowel syndrome. Pract Gastroenterol. 2007;20:3–9.Google Scholar
- 5.American Gastroenterological Association. The Burden of Gastrointestinal Diseases. Bethesda, MD: American Gastroenterological Association; 2001.Google Scholar
- 8.Drossman DA, Richter JE, Talley NJ, Corazziari E, Thompson WG, Whitehead WE. Functional gastrointestinal disorders. Boston: Little Brown; 1994.Google Scholar
- 10.Rome Foundation. Guidelines—Rome III diagnostic criteria for functional gastrointestinal disorders. J Gastrointestin Liver Dis. 2006;15:307–312.Google Scholar
- 30.Tauxe RV. Epidemiology of Campylobacter jejuni infections in the united states and other industrialized nations. In: Nachamkin I, Blaser MJ, Tompkins LS, eds. Campylobacter jejuni: Current and Future Trends. Washington: American Society for Microbiology; 1992:9–12.Google Scholar