Gene Expression in Effector T cells, wildtype of Thpok-deficient

The transcription factor Thpok is essential for CD4 T cell development in the thymus and remains expressed in post-thymic CD4 T cells. We post-thymically inactivated Thpok and compared microarray gene expression in Thpok-deficient CD4 T cells to that in their wildtype CD4 or CD8 counterparts We show that Thpok constrains the transcriptional circuitry to maintain CD4+-lineage integrity in naïve cells and to couple effector differentiation to environmental cues after antigenic stimulation. Redundantly with the related factor LRF, Thpok is continuously needed to prevent the trans-differentiation of mature CD4+ into -CD8+ T cells. We activated naïve CD4 T cells (either wild-type or Thpok-deficient) and CD8 T cells (wild-type) in vitro under Th1 conditions. Differentiated effectors were sorted 4 days after activation into CD4+CD8- and CD4-CD8+ (wild-type) and CD4+CD8- and CD4+CD8+ (Thpok-deficient) subsets. Total RNA was extracted from sorted subsets and processed for microarray analyses (Affymetrix Mouse Exon 1.0 ST array) at the NCI microarray facility, following the manufacturer’s recommendation. Data is from 3 replicates (except wild-type CD4-CD8+ cells, for which two samples only were processed), generated from two distinct cell preparations.