Analysis of Rejection after Fetal Cardiac Cell Transplantation in Comparison with Organ Transplantation

1)研究1将LEW（细胞同种异体移植组：CIG）和ACI（细胞同种异体移植组：CAG）大鼠培养的新生儿心肌细胞（6x10^6）移植至LEW心脏。将LEW与ACI异位异体器官移植（OAG）与CIA和CAG进行比较。在第14天的常规组织学中，共对9项与排斥反应相关的病理参数进行半定量分级。从第2天到第28天，CIG和CAG的所有动物都有大量的供体心肌细胞。CAG组白细胞浸润程度和心肌坏死程度较OAG组明显降低（P<0.01）。在大鼠心肌梗死诱导后4周，用PKH荧光染料标记ACI （n=8: CAG）和LEW （n=7: CIG）大鼠培养的新生心肌细胞（6x10^6）移植到LEW心脏中。7只大鼠只注射中剂量（对照组：COG）。各组均未进行免疫抑制。在COG组，面积变化百分比（% AC）和周向缩短百分比（%CS）在8周内不变。在CIG中，% AC和%CS在前4周有所改善，并在后4周继续增加。在CAG中，%AC和%CS在前4周得到改善，而随后没有观察到改善。CAG和cig56 d均可见大量PKH阳性细胞，且抗肌红蛋白抗体染色呈阳性。结论同种异体细胞移植的排斥反应小于器官移植。同种异体心肌细胞移植和同种异体心肌细胞移植后左心室功能均有明显改善。然而，同种异体心肌细胞移植是短暂的，并随着时间的推移再次下降

1) Study 1Cultured neonatal cardiomyocytes (6x10^6) from LEW (cell isograft group: CIG) and ACI (cell allograft group: CAG) rats were transplanted into LEW hearts. LEW to ACI heterotopic organ allografts (OAG) were compared with CIA and CAG. A total of 9 pathological parameters associated with rejection were semi-quantitatively graded in conventional histology at day 14. Large numbers of donor myocardial cells were present from day 2 through day 28 in all animals of the CIG and the CAG. The grades of leukocyte infiltration and myocardial necrosis were significantly reduced in the CAG compared with in the OAG (P<0.01). Minimal vascular pathology was observed in the vessels in the CAG, while severe vascular pathology was established in the OAG2) Study 2Four weeks after induction of myocardial infarction in rats, cultured neonatal cardiomyocyte (6x10^6) from ACI (n=8: CAG) and LEW (n=7: CIG) rats labeled with PKH fluorescent dye were transplanted into LEW hearts. Seven rats had medium injection only (Control group: COG). No immunosuppression was given in any groups. In COG, percent area change (% AC) and percent circumferential shortening (%CS) were unchanged over 8 weeks. In CIG, % AC and %CS were improved over the first 4 weeks and continued to be increased in the second 4 weeks. In CAG, %AC and %CS were improved over the first 4 weeks, while no subsequent improvement was observed. Large number of PKH positive cells, also positively stained with anti-myoglobin antibody was present at 56 day in CAG as well as CIGConclusionCell allograft transplantation revealed less rejection than organ transplantation. .Left ventricular functions were significantly improved after allogeneic cardiomyocyte transplantation as well as isogeneic cardiomyocyte transplantation. However, allogeneic cardiomyocyte transplantation was transient and declined again over time