Naturally Occurring and Inducible T-Regulatory Cells Modulating Immune Response in Allergic Asthma

Rationale: T-regulatory cells (Tregs) are potent immunomodulators in allergic asthma.Objectives: We evaluated the functional effects of Tregs by adoptively transferring naturally occurring CD4+CD25+ Tregs (NTregs) and CD4+CD25− inducible Tregs (iTregs) from lung and spleens of green fluorescent protein (GFP)-transgenic Balb/c mice into cockroach-sensitized and -challenged mice.Methods: GFP-labeled NTregs and iTregs were adoptively transferred into cockroach-sensitized and -challenged mice. Airway hyperresponsiveness (AHR) to methacholine was examined using a single-chamber, whole-body plethysmograph and invasive tracheostomy.Measurements and Main Results: Adoptive transfer of either NTregs or iTregs from lung or spleen reversed airway inflammation and AHR to methacholine, and the effect lasted for at least 4 weeks. GFP-labeled iTregs up-regulated CD25 and forkhead-winged transcriptional factor box protein 3 and migrated to lymph node and lung. Lung CD4+CD25+ T cells isolated from each group of recipient m...