Engineered cells with synthetic gene circuits can detect and respond to disease biomarkers. These could one day help to treat psoriasis, a chronic inflammatory skin disorder.

Clinical trials have shown that proteins called cytokines can help people who have psoriasis, but the cytokines need to be administered continuously. To overcome this, Martin Fussenegger at the Swiss Federal Institute of Technology in Zurich and his colleagues designed human cells to detect TNF and IL-22, two biomarkers that are associated with flare-ups of psoriasis. When the designer cells detect threshold levels of both biomarkers, they produce the cytokines. Implanting the cells in mouse models of skin inflammation prevented acute disease, improved skin lesions and restored normal skin. The cells were also responsive to blood samples from people with psoriasis.

Sci. Transl. Med. 7, 318ra201 (2015)