Department of Medicine, University of California, San Francisco, California 94143-1346, USA.
Cytotherapy. 2012 Feb;14(2):223-31. doi: 10.3109/14653249.2011.623690. Epub 2011 Oct 31.
We have shown previously that inhibition of the p38 mitogen-activated protein kinase (p38MAPK) directs the differentiation of human embryonic stem cell (hESC)-derived cardiomyocytes (hCM). We investigated the therapeutic benefits of intramyocardial injection of hCM differentiated from hESC by p38MAPK inhibition using closed-chest ultrasound-guided injection at a clinically relevant time post-myocardial infarction (MI) in a mouse model.
MI was induced in mice and the animals treated at day 3 with: (a) hCM, (b) human fetal fibroblasts (hFF) as cell control, or (c) medium control (n = 10 animals/group). Left ventricular ejection fraction (LVEF) was evaluated post-MI prior to therapy, and at days 28 and 60 post-cell therapy. Hearts were analyzed at day 60 for infarct size, angiogenesis, cell fate and teratoma formation.
LVEF was improved in the hCM-treated animals compared with both hFF and medium control-treated animals at day 28 (39.03 ± 1.79% versus 27.89 ± 1.27%, P < 0.05, versus 32.90 ± 1.46%, P < 0.05, respectively), with sustained benefit until day 60. hCM therapy resulted in significantly smaller scar size, increased capillary bed area, increased number of arterioles, less native cardiomyocyte (CM) apoptosis, and increased CM proliferation compared with the other two groups. These benefits were achieved despite a very low retention rate of the injected cells at day 60, as assessed by immunohistochemistry and quantitative real-time polymerase chain reaction (qPCR). Therapy with hCM did not result in intramyocardial teratoma formation at day 60.
This study demonstrates that hCM derived from p38MAPK-treated hESC have encouraging therapeutic potential.
我们之前已经证明，抑制丝裂原活化蛋白激酶 p38（p38MAPK）可促使人胚胎干细胞（hESC）衍生的心肌细胞（hCM）分化。我们通过在心肌梗死后（MI）的临床相关时间使用闭胸超声引导注射，研究了使用 p38MAPK 抑制分化的 hESC 衍生的 hCM 进行心肌内注射的治疗益处。
在小鼠模型中诱导 MI，并在第 3 天用以下方法治疗动物：（a）hCM，（b）人胎儿成纤维细胞（hFF）作为细胞对照，或（c）培养基对照（每组 n = 10 只动物）。MI 前评估左心室射血分数（LVEF），并在细胞治疗后第 28 天和第 60 天进行评估。在第 60 天，对心脏进行分析以确定梗死面积、血管生成、细胞命运和畸胎瘤形成。
与 hFF 和培养基对照组相比，hCM 治疗组在第 28 天的 LVEF 得到改善（39.03 ± 1.79%比 27.89 ± 1.27%，P < 0.05，比 32.90 ± 1.46%，P < 0.05），并且这种益处持续到第 60 天。hCM 治疗可导致梗死面积减小、毛细血管床面积增加、小动脉数量增加、内源性心肌细胞（CM）凋亡减少以及 CM 增殖增加，与其他两组相比。尽管通过免疫组织化学和实时定量聚合酶链反应（qPCR）评估，第 60 天注射细胞的保留率非常低，但仍能达到这些益处。hCM 治疗在第 60 天并未导致心肌内畸胎瘤形成。
本研究表明，p38MAPK 处理的 hESC 衍生的 hCM 具有令人鼓舞的治疗潜力。
