Regulatory T cells from colonic lamina propria [array]

The colonic lamina propria contains a distinct population of Foxp3+ T regulatory cells (Tregs) that modulate responses to commensal microbes. Analysis of gene expression revealed that the transcriptome of colonic Tregs is distinct from splenic and other tissue Tregs. Rorγ and Helios in colonic Tregs mark distinct populations: Rorγ+Helios- or Rorγ-Helios+ Tregs. We uncovered an unanticipated role for Rorγ, a transcription factor generally considered to be antagonistic to Foxp3. Rorγ in colonic Tregs accounts for a small but specific part of the colon-specific Treg signature. (1) Total colonic and splenic Foxp3+ Treg comparison: Lymphocytes were isolated from colonic lamina propria and spleens of Foxp3-ires-GFP mice, where GFP reports Foxp3 expression. TCRb+CD4+GFP+ cells were double sorted into Trizol. (2) Colonic Rorγ+ and Rorγ- Treg comparison: Foxp3-ires-Thy1.1 reporter mice were crossed to Rorc-GFP reporter mice to generate mice that report both Foxp3 and Rorγ expression. Rorγ+Foxp3+ Tregs (TCRb+CD4+Thy1.1+GFP+) and Rorγ-Foxp3+ Tregs (TCRb+CD4+Thy1.1+GFP-) from colonic lamina propria were double sorted into Trizol.To reduce variability and increase cell number, cells from multiple mice were pooled for sorting and at least three replicates were generated for all groups. RNA from 1.5-3.0 x104 cells was amplified, labeled and hybridized to Affymetrix Mouse Gene 1.0 ST Arrays.