Novel findings in drug-induced dendritic cell tolerogenicity.

Dendritic cells (DCs) constitute a unique set of antigen-presenting cells (APCs), equipped with the potential to initiate strong immune responses as well as to critically regulate immunity. Tolerogenic or "alternatively activated" DCs show remarkable properties in regulating immune responses both in vitro and in vivo. Furthermore, tolerogenic DCs are now beginning to be tested in clinical studies. Use of pharmacological agents to induce maturation-resistant tolerogenic DCs is a popular approach. In this review, we will discuss already recognized, as well as recently discovered, potential pharmacological agents, their mechanism of action, and the way in which they induce tolerance in DCs.