Decrease in CD4+CD25+FoxP3+ Treg cells after pulmonary resection in the treatment of cavity multidrug-resistant tuberculosis
Received 21 September 2009; received in revised form 3 February 2010; accepted 6 April 2010. published online 23 July 2010. Corrected Proof
Summary
Objectives
Immune regulatory mechanisms may limit the immunopathologic condition of infection with Mycobacterium tuberculosis and suppress cellular immune responses in the host. We investigated the CD4+CD25+FoxP3+ circulating regulatory T cells (Treg) in patients with cavity multidrug-resistant tuberculosis (MDR-TB) before and after surgery.
Methods
We compared the proportion of Treg cells in 13 patients with cavity MDR-TB pre- and postoperatively and in 10 healthy control subjects by flow cytometry using three specific markers in peripheral blood lymphocytes: cell-surface CD4 and CD25 expression and intracellular FoxP3 expression.
Results
The proportion of CD4+CD25high and CD4+CD25+FoxP3+ Treg was significantly higher in patients with cavity MDR-TB and at 1-month postoperatively than in healthy controls (p<0.001). The proportion of CD4+ and CD4+CD25− cells was significantly lower in patients with cavity MDR-TB than in controls (p<0.001). Pre- and postoperative proportions of CD4+CD25high and CD4+CD25+FoxP3+ Treg cells showed a positive correlation (r=0.878, p<0.001).
Conclusion
Circulating Treg cells are increased in proportion in patients with cavity MDR-TB and decreased after surgery. Infection with M. tuberculosis may induce Treg cell-surface molecular changes with increased numbers of cells.