TNF activates a distinct cellular program in human regulatory T cells

Here we show that tumor necrosis factor (TNF) induced in human T-regulatory cells (Treg), as compared to conventional T cells (Tcon), a transcription program highly enriched for typical NF-κB target genes, such as: the cytokines LTA and TNF; the TNF-receptor super family members FAS, 4-1BB and OX-40; various anti-apoptotic genes; and other important immune-response genes. As an initial approach to examine the cellular program induced by TNF in Tregs versus Tcon cells, we employed microarray gene expression analysis at 2 and 24 hrs following TNF treatment. Highly pure CD4+ CD25+/hi Treg and CD25- Tcon cells, obtained by FACSAria-based cell-sorting, were either treated with 50ng/mL of TNF or left untreated, for 2 and 24 hours to detect both early and late changes in gene transcription. Total RNA extracted from the various samples were analyzed using the Affymetrix HU GENE 1.0 ST Array platform for changes in gene-transcripts induced by TNF as compared to untreated media control samples.