Deciphering the epigenetic code of T lymphocytes

The multiple lineages and differentiation states that constitute the T-cell compartment all derive from a common thymic precursor. These distinct transcriptional states are maintained both in time and after multiple rounds of cell division by the concerted actions of a small set of lineage-defining transcription factors that act in conjunction with a suite of chromatin-modifying enzymes to activate, repress, and fine-tune gene expression. These chromatin modifications collectively provide an epigenetic code that allows the stable and heritable maintenance of the T-cell phenotype. Recently, it has become apparent that the epigenetic code represents a therapeutic target for a variety of immune cell disorders, including lymphoma and acute and chronic inflammatory diseases. Here, we review the recent advances in epigenetic regulation of gene expression, particularly as it relates to the T-cell differentiation and function.