Dr. Alegre leads a research laboratory focused on T cell responses in the contexts of transplantation, autoimmunity, and cancer, with a strong foundation in mouse models and a growing emphasis on clinical translation. A primary focus of the lab is on T cell tolerance in transplantation and the ways in which infections and inflammatory events influence the induction and maintenance of that tolerance.

Dr. Alegre’s work has demonstrated that transplantation tolerance exists along a spectrum of robustness, depending on how many mechanisms of T cell tolerance are activated. Importantly, infections and inflammation can compromise these mechanisms and erode tolerance. This line of investigation has also revealed that bacterial infections not only impact transplant outcomes directly but also modulate immune responses through the microbiota. Dr. Alegre's team has shown that manipulating the microbiota can enhance graft survival, offering new therapeutic opportunities.

On the clinical side, Dr. Alegre has led studies examining the immunology of transplant recipients and patients infected with bacteria that influence transplant outcomes. In collaboration with other investigators, Dr. Alegre has extended this research to explore how the microbiota affects the responsiveness of melanoma patients to immunotherapy, bridging fundamental immunology with translational and clinical applications.