To minimize the risk of immunologic rejection, an immunosuppression regimen informed by established protocols and current practices in clinical lung transplantation was used (Fig. 1B). Four hours before initiation of xenogeneic XC, xeno-support swine were anesthetized, intubated, and administered CVF (1 mg; Sigma-Aldrich) to deplete complement activity (61 (link), 62 (link)). Intravenous diphenhydramine (50 mg; West-Ward Pharmaceuticals) and methylprednisolone (1 g; Pfizer) were administered to mitigate hemodynamic instability occasionally associated with CVF. Intravenous tacrolimus (5 mg; Astellas) and mycophenolate (500 mg; Genentech) were also administered before reperfusion and redosed every 12 hours. methylprednisolone (125 mg; Pfizer) was readministered every 8 hours after the initial dose.