Bacterial superantigens and T cell receptor β-chain-bearing T cells in the immunopathogenesis of ulcerative colitis

Authors: Shiobara, N.; Suzuki, Y.¹; Aoki, H.¹; Gotoh, A.; Fujii, Y.; Hamada, Y.²; Suzuki, S.³; Fukui, N.⁴; Kurane, I.⁵; Itoh, T.⁶; Suzuki, R.⁴

Source: Clinical & Experimental Immunology, Volume 150, Number 1, October 2007 , pp. 13-21(9)

Publisher: Blackwell Publishing

Key:

- Free Content

- New Content

- Subscribed Content

- Free Trial Content

Abstract:

Summary

Ulcerative colitis (UC) is a chronic relapsing-remitting inflammatory bowel disease (IBD) that affects the colon and the rectum producing debilitating symptoms, which impair ability to function and quality of life. The aetiology of IBD is incompletely understood, but within the lymphocyte population, specific T cell subsets are known to be major factors in the development of intestinal immune pathology while different subsets are essential regulators, controlling IBD. Hence, IBD is thought to reflect dysregulated T cell behaviour. This study was to investigate if the normal molecular configuration of the T cell receptor (TCR) repertoire is compromised in patients with UC. The percentage of T cell-bearing β-chain 4 (TCRBV4) was high in patients with UC, and T cells showed polyclonal expansion in the presence of bacterial superantigens (SA) such as streptococcal mitogenic exotoxin Z-2 (SMEZ-2), indicating that bacterial SA promote specific TCRBV family expansion. Further, in patients with UC, the duration of UC was significantly longer in patients with skewed TCRBV4 compared with patients without TCRBV4 skewing, suggesting that long-term exposure to bacterial SA such as SMEZ-2 might promote systemic immune disorders like the remission-relapsing cycles seen in patients with UC. In conclusion, our observations in this study support the perception that the systemic activation of T cells by enteric bacterial SA might lead to a dysregulated, but exuberant immune activity causing the remission and flare-up cycle of mucosal inflammation in patients with UC. Future studies should strengthen our findings and increase understanding on the aetiology of IBD.

Keywords: bacterial superantigens; inflammatory bowel disease; T lymphocytes; TCR repertoire; ulcerative colitis

Document Type: Research article

DOI: 10.1111/j.1365-2249.2007.03443.x

Affiliations: 1: Internal Medicine, Sakura Medical Center, Toho University, Sakura, 2: First Department of Oral and Maxillofacial Surgery, School of Dental Medicine, Tsurumi University, Yokohama, 3: Section of Biological Science, Research Center for Odontology, Nippon Dental University School of Life Dentistry at Tokyo, and 4: Department of Rheumatology and Clinical Immunology, Clinical Research Center for Allergy and Rheumatology, National Sagamihara Hospital, Sagamihara, 5: Department of Virology I, National Institute of Infectious Diseases, Tokyo, 6: Division of Immunology and Embryology, Department of Cell Biology, Tohoku University School of Medicine, Sendai, Japan

You have access to the full text article on a website external to Ingentaconnect.

Please click here to view this article on InterScience.

You may be required to register and activate access on InterScience before you can obtain the full text. If you have any queries please contact onlinehelp@oxon.blackwellpublishing.com

Key:

- Free Content

- New Content

- Subscribed Content

- Free Trial Content

Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages.