Regulatory T Cells Are Expanded in Blood and Disease Sites in Patients with Tuberculosis

• DOI: 10.1164/rccm.200508-1294oc
• Publication Date: 2005-12-10T01:43:56Z
• Authors: Valerie Guyot-Revol; John A. Innes; Sarah Hackforth; Tim Hinks; Ajit Lalvani
• Keywords: Regulatory T cell; Ex vivo; Cellular immunity

Rationale: T-cell responses during tuberculosis (TB) help contain Mycobacterium in vivo but also cause collateral damage to host tissues. Immune regulatory mechanisms may limit this immunopathology, and suppressed cellular immune patients with TB suggest the presence of activity. CD4+CD25high T cells mediate immunity several chronic infections have not been described TB.Objective: To determine whether are increased they suppress responses.Methods: We compared frequency circulating 27 untreated 23 healthy control subjects using two specific markers: cell-surface CD25 expression FoxP3 mRNA peripheral blood mononuclear cells.Measurements Main Results: detected a threefold increase (p < 0.001) 2.2-fold = 0.006) TB, there was positive correlation between these markers (r 0.58, p 0.001). Increased interleukin-10 transforming growth factor-β1 did correlate markers. Ex depletion from resulted numbers M. antigen–specific IFN-γ–producing seven eight 0.005). Finally, 2.3-fold extrapulmonary purely pulmonary 0.01) amplified 2.6-fold at disease sites relative 0.043).Conclusions: Regulatory expanded contribute suppression Th1-type responses.