He has been an independently-funded researcher for over 20 years with research interests that include basic and transplant immunology, the pathophysiology of kidney disease and stem cell and regenerative therapies. The scope of his research includes laboratory studies involving cultured cells and disease models as well as immunological profiling studies and early-stage clinical trials in patients. As a REMEDI investigator, he has led research projects funded by Science Foundation Ireland, the European Commission and the Irish Research Council to explore the immunological effects of allogeneic (healthy donor) mesenchymal stromal cells (allo-MSCs) as potential regenerative therapies for a range of disease conditions including diabetic kidney disease, sepsis-associated kidney disease and corneal transplantation.