Apoptosis of regulatory T lymphocytes is increased in chronic inflammatory bowel disease and reversed by anti-TNFα treatment. Issue 10 (1st April 2011)

• Record Type: Journal Article
• Authors: Veltkamp, Claudia; Anstaett, Matthias; Wahl, Kristin; Möller, Sarah; Gangl, Saskia; Bachmann, Oliver; Hardtke-Wolenski, Matthias; Länger, Florian; Stremmel, Wolfgang; Manns, Michael P; Schulze-Osthoff, Klaus; Bantel, Heike
• Is Part Of: Gut. Volume 60:Issue 10(2011)
• Page Start: 1345
• Page End: 1353
• Publication Date: 2011-04-01
• Subjects: Apoptosis -- inflammatory bowel disease -- Treg cells -- caspases -- anti-TNFα; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.2010.217117
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Background and aims: Inappropriate immune responses contribute to the continuous stimulation of the intestinal immune system in chronic inflammatory bowel disease (IBD). Among several pathogenic factors, a numerical deficiency of regulatory T (Treg) cells has been suggested to lead to an insufficient compensation of chronically activated T lymphocytes. This study was conducted to investigate whether increased apoptosis contributes to Treg cell deficiency in IBD and whether successful treatment with antitumour necrosis factor α (TNFα) is achieved by reducing of Treg cell apoptosis. Methods: Apoptosis of CD4 + Foxp3 + Treg cells in tissue sections of patients with active IBD was analysed by immunohistochemistry and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labelling) staining. Apoptosis of peripheral blood CD4 + CD25 + Foxp3 + Treg cells was investigated by flow cytometry and annexin-V staining. In addition, caspase activity and apoptosis were measured in sera of patients with IBD treated with anti-TNFα by a luminometric caspase enzyme assay. Results: It is demonstrated that patients with active IBD revealed increased apoptosis of local CD4 + Foxp3 + Treg cells in the inflamed mucosa compared with non-inflamed control colon tissue. Moreover, in peripheral blood a reduced frequency and increased apoptosis of Treg cells were found and accompanied by elevated caspase activity in the serum. During anti-TNFα treatment, Treg cell apoptosis declined in close correlation with elevated peripheral Treg cell numbers and a decrease of caspase activation and disease activity. Conclusions: These data suggest that increased apoptosis of Treg cells plays a potentially important role in the pathogenesis of IBD and can be reversed by anti-TNFα treatment. Measurement of Treg cell apoptosis and serum caspase activity might therefore represent promising tools for monitoring disease activity and treatment response in patients with IBD.