Xiao Yong-Fu
Stem Cell Research Laboratory, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
Sheng Li Xue Bao. 2003 Oct 25;55(5):493-504.
Cardiomyocytes deceased during myocardial infarction (MI) are replaced with non-contractile scar tissue, which has a great chance to cause heart failure. Repair of dead or injured myocardium and improvement of cardiac function remain a serious challenge for the therapy of heart failure. Recently, stem cells have been transplanted in experimental settings to replace lost myocardium. This article summarizes the recent experimental findings on transplantation of embryonic stem cells (ESCs) and their derived cells in animals with myocardial injury and highlights the progresses in research of these particular cell types. Beneficial effects of cell transplantation with other cell types in injured hearts have been detailed in other reviews. ESCs are pluripotent cells derived from early mammalian embryos at the blasto-stage. These cells have the capacity for prolonged undifferentiated proliferation or differentiation into all of specialized somatic cell types of the body in culture, including cardiomyocytes. Because of the great ability of proliferation and differentiation to mature tissues, ESCs are a potential valuable resource for cell therapy targeting regeneration of functional myocardium in diseased hearts. In recent animal studies intramyocardial transplantation of ESCs or their differentiated cardiac-like cells regenerated injured myocardium and improved heart function in infarcted animal models. In addition, intravenous infusion of ESCs significantly increased the survival rate and attenuated myocardial injury in viral myocarditic mice. Development and characterization of cardiomyocytes in vitro from human ESCs have been reported recently. However, many ethical, political, and scientific barriers have to be overcome before clinical utilization of human ESCs and their differentiated cells for treating end-stage cardiac diseases.
心肌梗死（MI）期间死亡的心肌细胞会被无收缩能力的瘢痕组织替代，这很可能导致心力衰竭。修复死亡或受损的心肌以及改善心脏功能仍然是心力衰竭治疗面临的严峻挑战。最近，在实验环境中已进行干细胞移植以替代丢失的心肌。本文总结了胚胎干细胞（ESC）及其衍生细胞在心肌损伤动物中移植的最新实验结果，并突出了这些特定细胞类型的研究进展。其他综述已详细阐述了其他细胞类型在受损心脏中进行细胞移植所产生的有益效果。胚胎干细胞是源自囊胚期早期哺乳动物胚胎的多能细胞。这些细胞在培养中具有长时间未分化增殖的能力，或能分化为体内所有特化的体细胞类型，包括心肌细胞。由于胚胎干细胞具有向成熟组织增殖和分化的强大能力，它们是针对患病心脏功能性心肌再生的细胞治疗潜在的宝贵资源。在最近的动物研究中，胚胎干细胞或其分化的类心脏细胞的心肌内移植使梗死动物模型中受损的心肌再生，并改善了心脏功能。此外，静脉输注胚胎干细胞显著提高了病毒性心肌炎小鼠的存活率并减轻了心肌损伤。最近已有报道从人类胚胎干细胞体外发育和鉴定心肌细胞的情况。然而，在将人类胚胎干细胞及其分化细胞临床用于治疗终末期心脏疾病之前，必须克服许多伦理、政治和科学障碍。
