Resumen
Adoptive immunotherapy has emerged as an effective alternative of mounting impact to the current standard of care in cancer, viral infections, and recently, autoimmunity. Key players in maintaining immune homeostasis are the regulatory T cells (Tregs), a major immunosuppressive cell subset and, therefore, an attractive candidate for the cellular therapy of autoimmune disorders or allo-responses in the transplantation setting. Notwithstanding the safety and tolerability of Tregs in early trials, their efficacy remains rather ill-defined, being limited by poor persistence and a lack of specificity, thus hindering widespread clinical application. However, the better biological understanding of in vivo Treg performance and the recent advances in genetic engineering have led to the next-generation Treg immunotherapy era, enabling the introduction of new features in Tregs and generating more potent and targeted Treg cellular therapies. In this review, we discuss the current achievements and existing challenges towards clinically translating Tregs into a living drug therapy for a variety of inflammatory conditions.