Table 1.

Potential physiologic incompatibility between xenograft and recipient.

Organ	Potential incompatibility
Kidney	Electrolyte differences (primarily calcium, phosphorus, and potassium) leading to imbalances in recipient Erythropoietin and renin structure dissimilarity between porcine donors and recipients causing anemia and hypoaldosteronism Protein wasting in renal xenografts contributing to hypoalbuminemia and graft loss Hypertensive nephrosclerosis due to higher blood pressures in recipient than in porcine donor
Heart	Maladaptive hypertrophy in porcine xenografts resulting in diastolic heart failure Higher blood pressures in NHP/human recipient resulting in xenograft hypertrophy
Liver	Lower circulating albumin in porcine donors leading to decreased production and hypoalbuminemia in recipient Coagulopathy, thrombotic microangiopathy, and subsequent graft loss due to uncontrolled activation of the coagulation cascade and contributing to severe thrombocytopenia Potential amino acid differences in protein production leading to changes in function and functional deficiency