The role of innate immunity in donor organ procurement

Solid organ transplantation is a life saving procedure for patients with end-stage organ disease, and great care is taken to ensure that healthy organs are procured from deceased or live donors. Despite rigorous efforts to avoid injury, all organs experience some degree of damage from a process called ischemia reperfusion injury (IRI). The first part of the injury (ischemia) occurs when the donor organ's blood supply is compromised, and the second part (reperfusion) occurs when the blood supply is reestablished. The pathophysiology of the IRI is complex, but data from many laboratories have demonstrated that the inciting events of ischemia/reperfusion injury are triggered through a phylogenetically conserved system called the innate immune system. The innate immune system is a complex array of molecules, receptors and cellular elements present in species as diverse as plants to humans. This review discusses the role of the innate immune system in renal IRI and focuses on mechanisms of injury during organ procurement and transplantation. Although there are overlapping complex mechanisms, blockade of the innate immune system will likely provide a novel approach to preventing the earliest events associated with renal ischemia. Potentially, blockade of innate immune activation will provide the opportunity to increase the use marginal donors, especially those from patients deceased after cardiac death.