Exploration Of Human Induced Pluripotent Stem Cell-derived Cardiomyocytes As A Therapy Strategy In Ischemic Heart Failure

Pharmacological and engraftment studies of human induced pluripotent stem cell-derived cardiomyocytes in non-human primate coronary artery ligation and reperfusion injury modelBackground:Coronary artery stenosis or occlusion leading to myocardial dysfunction is the main cause of heart failure.However,current treatment options are difficult to completely cure or alleviate the condition.The application of stem cells to regenerate myocardial cells by differentiation potential and repair damaged myocardial tissue has become a potential novel therapeutic approach for heart failure.Induced pluripotent stem cells(iPSCs)can differentiate into a large number of cardiomyocytes,which can be used for exogenous replenishment of myocardial cells to treat heart failure.The therapeutic effectiveness of human induced pluripotent stem cell-derived cardiomyocytes(hiPSCCMs)in restoring cardiac function in large animal models and their in vivo engraftment following transplantation are yet unknown,nevertheless.Objectives:This study aimed to evaluate the effect of intramyocardial inj ection of hiPSCCMs on the improvement of cardiac function and structure,and assess their in vivo engraftment,using non-human primates(NHP)to construct an ischemia-reperfusion injury model.Methods:In this study,GMP-grade hiPSC-CMs prepared by Nanjing HELP Therapeutics were used.A total of 20 rhesus monkeys were induced with ischemia-reperfusion injury by left anterior descending coronary artery ligation and divided into HiCM group(n=10),Vehicle group(n=6),and Model group(n=4),HiCM group received intramyocardial injection of 1.0×108 hiPSC-CMs/animal and immunosuppressive therapy,vehicle group received the same volume of 5%human serum albumin and model group received no treatment.The effects of intramyocardial injection of 1.0×108 hiPSC-CMs on the cardiac contractile function and structural remodeling of cynomolgus monkeys were evaluated by echocardiography,magnetic resonance imaging,biopsy and histology.In addition,two healthy cynomolgus monkeys were selected to receive intramyocardial injection of 89Zrlabeled hiPSC-CMs and 89Zr-oxine under thoracotomy,and the distribution of cells at each time point was observed under PET/CT.Results:Twenty rhesus monkeys were subjected to form an ischemia-reperfusion injury model by reperfusion after ligation of the left anterior descending coronary artery for 3 hours.After receiving treatment based on their respective groups,they were observed for three months.Echocardiography showed that ejection fraction(EF)and fractional shortening(FS)in HiCM group showed a recovery trend at 1 month after operation;At 3 months after operation,EF,FS,end-systolic volume(ESV),stroke volume(SV),left ventricular internal diameter at end-systole(LVIDs),end-systolic interventricular septum thickness and end-diastolic interventricular septum thickness in HiCM group were restored to or higher than those at 1 week after operation.MRI revealed that the percentage of delayed enhancement volume of the heart in the HiCM group recovered three months after surgery,compared to one month after surgery.HE staining revealed that there was no difference between the HiCM group and the Vehicle group in terms of myocardial fibrosis and inflammation.Immunofluorescence staining revealed that cardiac troponin I,a specific marker of exogenous hiPSC-CMs,was still detectable 1 month after treatment in the myocardial tissue of the HiCM group.After three months,no exogenous hiPSC-CMs were detected in the heart tissues of any animal.According to PET/CT,hiPSC-CMs could colonize the heart for up to seven days.Conclusions:Injecting 1.0×108 cells of hiPSC-CMs intramyocardially into rhesus primates significantly improved cardiac function and cardiac structure damage caused by ischemia-reperfusion injury,and inhibited the progression of heart failure.Intramyocardial injection of hiPSC-CMs could survive in NHP for at least 1 month,and after 3 months,no hiPSC-CMs remained.Early clinical results of epicardial injection of allogeneic human induced pluripotent stem cell-derived cardiomyocytes in patients with advanced heart failureBackground:Coronary artery occlusion causes myocardial ischemia and hypoxia,resulting in local necrosis and loss of a significant number of cardiomyocytes,which is the primary cause of ischemic heart failure.In vitro differentiation of human induced pluripotent stem cells(hiPSCs)into highly purified cardiomyocytes represents a novel therapeutic approach for heart failure.In animal models of subacute myocardial infarction,transplantation of hiPSC-derived cardiomyocytes(hiPSC-CMs)has been shown to improve cardiac contractile function.However,the safety and efficacy of hiPSC-CMs transplantation for the treatment of patients with ischemic heart failure remain unclear.Objectives:To assess the safety and preliminary efficacy of intramyocardially administrated allogeneic hiPSC-CMs therapy in patients with ischemic heart failure undergoing coronary artery bypass grafting(CABG)surgery.Methods:This was a single-center,single-blind and randomized controlled clinical trial initiated by the investigators.Twelve patients with ischemic heart failure(20%≤ejection fraction<45%)were randomly assigned to the cell therapy group(n=6)received CABG surgery and concolitant epicardial injection of 2.0×108 allogeneic hiPSC-CMs,whereas the control group(n=6)received CABG surgery alone.The primary endpoint of the study was safety evaluation six months after surgery,including:(1)the incidence of newly developed tumors,as determined by head,chest,and abdominal CT scans and PET/CT imaging;(2)the incidence of sustained ventricular tachycardia lasting more than 30 seconds within one to six months after surgery.This trial was approved by the Ethics Committee of Nanjing Drum Tower Hospital(No.SC202000103)and registered in ClinicalTrials.gov(NCT03763136).Results:In the follow-up period of 1 to 6 months after surgery,neither the cell therapy nor the control groups observed any new tumors or ventricular tachycardia lasting more than 30 seconds.Thus,reaching the primary endpoint.The most common adverse event of allogeneic hiPSC-CMs treatment was perioperative ventricular arrhythmia,mainly manifested as accelerated ventricular spontaneous rhythm and ventricular tachycardia.Improvements in cardiac function were observed in both the cell therapy and control groups.CMR revealed that ventricular wall motion and time of maximal thickness improved in the area of cell transplantation after treatment in the cell therapy group,but not in the control group.This could infer that transplantation of allogeneic hiPSC-CMs could improve the myocardial contractile function of the transplanted area.Conclusions:Our study verified preliminary feasibility of epicardial injection of allogeneic human induced pluripotent stem cell-derived cardiomyocytes in patients undergoing coronary artery bypass grafting surgery.The primary endpoint was reached,which provided foundation for subsequent more reasonable large-scale clinical trials.