Genetic determinants of delayed graft function after kidney transplantation

Intracellular concentration of reactive oxygen species is held within tight physiological limits by enzymes with scavenging and repair functions. Under extreme conditions such as prolonged cold ischemia, these enzymes may be unable to adequately protect the organ, resulting in reperfusion injury that renders the graft dysfunctional after transplantation. In this study, we investigated normal human variation of some of these inducible enzymes to determine if certain phenotypes could be identified that are associated with a reduced risk of delayed graft function (DGF).

Polymerase chain reaction was performed to differentiate polymorphisms for manganese superoxide dismutase and three classes of glutathione-S-transferase in donors and recipients of transplants with over 24 hr of cold ischemia. The data attained was analyzed compared with the presence or absence of DGF, defined as the requirement of hemodialysis in the first week after transplantation.

Enzyme polymorphisms were defined for 229 recipients and 104 of their respective donors. Patients receiving a kidney from a donor who expressed GSTM1*B either alone or in combination with GSTM1*A experienced significantly lower rates of DGF (P <0.05). No association was found between any enzyme polymorphism in the recipients and the development of DGF.

The identification of a genetic allele, which is protective against reperfusion injury, generates the possibility for defining polymorphisms at the time of tissue typing to give insight to the inherent biological risk of DGF that an organ possesses.