Regulatory T-cells: receptors, repertoires and roles in disease.

In the 20-or-so years that immunologists have spent describing the mechanisms and functions of regulatory T-cells, a very great deal has been learnt: a T-cell subset once described for the generic ability to harness autoimmunity in vivo or diminish T-cell proliferation in vitro is now appreciated to act on a plethora of cellular pathways using a diverse array of mechanisms. Recent studies have shed new light on basic and applied aspects of Treg function, including T-cell receptor usage, specialist functions of tissue-resident Tregs, and the therapeutic consequences of tuning Treg function up or down for applications in autoimmunity or cancer, respectively.