The current treatment for liver failure is restricted to surgical liver transplantation, which is technically complicated, limited by the shortage of available organs and presents major risks to the patient. Bone marrow mesenchymal stem cells (BMSCs) represent promising sources of hepatocyte-like cells for cell transplantation treatment. However, a safe and efficient induction method for their differentiation remains to be defined. Here we further optimized an effective technique by combining high-dose treatment with hepatocyte growth factor (HGF) and ultrasound stimulation. The optimized ultrasound parameter (1.0 W/cm2 intensity, 1 MHz frequency, 20% duty cycle, 100 Hz pulse repetition frequency, 60-s irradiation duration, triple times in three days) combined with different HGF doses (10, 20 and 50 ng/ml) was used to treat BMSCs. The results showed that the specific hepatic markers, including α-fetoprotein (αFP/AFP), cytokeratin 18 (CK18), albumin (ALB) and glycogen, were increased in a dose-dependent manner. Their concentration was then further increased when ultrasound irradiation was administered (P < 0.05), as indicated by PCR, Western blot and immunofluorescence staining as well as a glycogen synthesis test. Furthermore, analysis of the hepatocyte-derived chemokines showed elevated stromal cell-derived factor 1alpha (SDF-1α) and C-X-C chemokine receptor type 4 (CXCR4) after HGF treatment. Again, concentrations of those chemokines were further increased by ultrasound radiation (P < 0.05). The observed increased effect was sustained for 21 days. To summarize, we further defined the optimal combination of HGF and ultrasound treatment to increase the differentiation and chemotaxis of BMSCs in a safe, sustained and efficient manner. These findings provide a new perspective for stem cell orientation in the field of tissue engineering.

中文翻译：

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超声驱动肝分化的人骨髓间充质干细胞长期生产糖原和肝源性，促进细胞侵袭的趋化因子。

当前用于肝衰竭的治疗仅限于外科手术肝移植，这在技术上是复杂的，受可用器官的短缺的限制并且给患者带来了重大风险。骨髓间充质干细胞（BMSC）代表了有希望的肝样细胞用于细胞移植治疗的来源。然而，仍然需要定义一种安全有效的分化方法。在这里，我们通过将大剂量治疗与肝细胞生长因子（HGF）和超声刺激相结合，进一步优化了一种有效的技术。优化的超声参数（1.0 W / cm2强度，1 MHz频率，20％占空比，100 Hz脉冲重复频率，60 s辐照时间，三天三倍）结合了不同的HGF剂量（10、20和50 ng） / ml）用于治疗BMSC。结果表明，包括α-甲胎蛋白（αFP/ AFP），细胞角蛋白18（CK18），白蛋白（ALB）和糖原的特异性肝标记物呈剂量依赖性增加。PCR，Western印迹和免疫荧光染色以及糖原合成测试表明，当进行超声波照射时，它们的浓度进一步增加（P <0.05）。此外，对肝细胞衍生趋化因子的分析显示，HGF治疗后基质细胞衍生因子1α（SDF-1α）和CXC趋化因子受体4型（CXCR4）升高。再次，这些趋化因子的浓度通过超声辐射进一步增加（P <0.05）。观察到的增强作用持续21天。总而言之，我们进一步定义了HGF和超声治疗的最佳组合，以安全，持续和有效的方式增加BMSC的分化和趋化性。这些发现为组织工程领域中干细胞定向提供了新的视角。