Comparative transcriptional profiling of medullary and cortical thymic cell types identifies epigenetic and transcription factors that uniquely define the mTEChi and cTEC lineages.

The thymus has the unique ability to impart lymphocytes in trans the concept of self-tolerance by negative selection and to enforce positive selection of lymphocytes that express optimal T-cell receptors (1,2). The thymus possesses a cortex and a medulla (4), and epithelial cells known as mTEC and cTEC are intimately involved in these processes (5). Here I compared the transcriptomes of mTEChi and cTEC (6) using global differential gene expression analysis. I present a series of epigenetic molecules and transcription factors that represent the most significant differences in the global gene expression profiles between these two cell types.