Our research arose from deep roots in transplant Immunobiology but in recent years has extended to tumor immunology and also tissue injury. A major focus nowadays is the biology of Foxp3+ T-regulatory (Treg) cells and how the functions of these cells can be usefully increased (autoimmunity, transplantation) or decreased (oncology) by pharmacologic approaches. These studies began with studies of functions of histone/protein deacetylases (HDACs) and histone/protein acetyltransferases (HATs) in Tregs, and have now grown to encompass additional levels of regulation, such as deubiquitinases (DUBs), and applications of HAT and HDAC targeting beyond Treg cells, including ischemia/reperfusion injury (IRI).