This Article Full Text Full Text (PDF) Other Versions of this Article: IAI.00553-07v1 75/9/4334    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Beswick, E. J. Articles by Reyes, V. E. Search for Related Content PubMed PubMed Citation Articles by Beswick, E. J. Articles by Reyes, V. E.

Expression of the Programmed Death Ligand 1, B7-H1, on Gastric Epithelial Cells after Helicobacter pylori Exposure Promotes Development of CD4⁺ CD25⁺ FoxP3⁺ Regulatory T Cells

Departments of Pediatrics,¹ Internal Medicine,² Biochemistry and Molecular Biology,³ Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas 77555⁴

Received 17 April 2007/ Returned for modification 22 May 2007/ Accepted 31 May 2007

During Helicobacter pylori infection, T cells are recruited to the gastric mucosa, but the host T-cell response is not sufficient to clear the infection. Some of the recruited T cells respond in a polarized manner to a Th1 response, while others become anergic. We have previously shown that T-cell anergy may be induced during infection by the interaction of T cells with B7-H1, which is up-regulated on the gastric epithelium during H. pylori infection. Recently, regulatory T (Treg) cells with a CD4⁺ CD25^high FoxP3⁺ phenotype were found at an increased frequency in the gastric mucosa of biopsy specimens from H. pylori-infected patients. While Treg cells are important in maintaining tolerance, they can also suppress immune responses during infection. In this study, we examined the induction of the Treg phenotype when naïve T cells were incubated with gastric epithelial cells exposed to H. pylori. The frequency of this phenotype was markedly decreased when B7-H1 was blocked with monoclonal antibodies or its expression was blocked with small interfering RNA. The functional role of these Treg cells was assessed in proliferation assays when the cells were cocultured with activated T cells, which effectively decreased proliferation of the cells.

Published ahead of print on 11 June 2007.

Editor: R. P. Morrison

This article has been cited by other articles:

• Alderson, K. L., Zhou, Q., Berner, V., Wilkins, D. E. C., Weiss, J. M., Blazar, B. R., Welniak, L. A., Wiltrout, R. H., Redelman, D., Murphy, W. J. (2008). Regulatory and Conventional CD4+ T Cells Show Differential Effects Correlating with PD-1 and B7-H1 Expression after Immunotherapy. J. Immunol. 180: 2981-2988 [Abstract] [Full Text]