After receiving his MD PhD degree from the University of Turin (Italy) and a Postdoc with G.T. Nepom at the Benaroya Institute in Seattle, R. Mallone moved to Paris in 2005. He is currently Professor of Immunology at Université Paris Cité and Diabetologist at the Cochin Hospital. He co-leads with Dr S. You a research team at the INSERM Cochin Institute and a satellite research lab at the Indiana Biosciences Research Institute in Indianapolis. His research spans from preclinical studies with human samples and mouse models to clinical trials. It focuses on autoimmune T cells and their dialogue with pancreatic beta cells to understand T1D mechanisms and develop novel biomarkers and therapeutics. He is Board member of the EU INNODIA.org network and US nPOD Key Question task force. He is French coordinator of several ongoing trials and for setting up a screening and care pathway for preclinical T1D. He is Associated Editor of Diabetologia. Major contributions to the field include: the demonstration of the role of CD8+ T cells in beta-cell autoimmunity; the existence of a universal state of ‘benign’ islet autoimmunity imprinted in the thymus; the description of the antigen display (immunopeptidome) of human beta cells and of the antiviral T-cell responses mounted against Coxsackieviruses; the development of T-cell assays to clarify disease mechanisms and therapeutic modifications; and the exploration of perinatal tolerogenic vaccination strategies.