In this review, Abul K. Abbas (a name which needs absolutely no introductions) and collegues revised the history, biology, genetics and the therapeutic approaches based on IL-2 known so far.
Interleukin-2 (IL-2) is one of the most important cytokines of adaptive immunity. It was first identified as a principal autocrine mitogenic factor for T cells, as well as being the first product of recombinand DNA technology to be used as immuno-boosting treatment for human experimentation in pathologies in which immune modulation was a promising therapeutic strategy (e.g. cancer or AIDS). However, its role in adaptive immune response, as it was later discovered, goes well beyond that of a "mere" aspecific growth factor for T cells. Quite soon, in fact, researcers had to deal with the baffling evidence that patients with autoimmune disease displayed low production of IL-2, while mouse models with compromised IL-2 signal axis developed autoimmune conditions, a puzzle that was clarified only when Tregs were discovered.