Cardiomyocyte bridging between hearts and bioengineered myocardial tissues with mesenchymal transition of mesothelial cells
Cardiomyocyte bridging between hearts and bioengineered myocardial tissues with mesenchymal transition of mesothelial cells
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DOI：
10.1016/j.healun.2005.09.017
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发表时间：
2006-03-01
影响因子：
8.9
通讯作者：
Okano, T
中科院分区：
文献类型：
--
作者：
Sekine, H;Shimizu, T;Okano, T
背景资料：对于三维（3D）组织的重建，我们利用了一种原始的组织工程方法，该方法将从温度响应培养皿中收获的单个细胞片层。堆叠的心肌细胞片表现出电和形态学通信，导致同步跳动的心肌组织。当这些生物工程3D组织移植物被移植到受损的心脏上时，移植物和宿主之间的间隙连接通讯可能对同步跳动和功能改善至关重要。在这项研究中，这些移植到心脏的形态学communications进行了examined.Methods：新生大鼠心肌细胞片收获的温度响应培养皿和分层创建3D组织。然后将这些构建体移植到梗塞的大鼠心脏上。进行组织学分析和透射电子显微镜（TEM）检查形态学通讯。小分子通过功能间隙连接也检测使用染料转移assay.Results：移植心肌细胞桥接移植物和心脏之间的完整地区。缝隙连接蛋白43染色和透射电镜显示桥接心肌细胞间存在缝隙连接和闰盘。此外，证实了低分子荧光染料钙黄绿素通过桥接心肌细胞从移植物转移到心脏。抗细胞间粘附分子-1抗体的免疫组化显示，间皮细胞在心外膜分散和转分化成间充质细胞之间的移植物和host.Conclusions：直接附着的分层心肌细胞片的心脏表面促进间皮细胞转分化和心肌细胞桥接，导致功能性通信通过缝隙连接。这些结果表明，这些生物工程心肌组织可以通过同步跳动改善受损的心脏功能。
Background: For the reconstruction of 3-dimensional (3D) tissues, we exploited an original method of tissue engineering that layers individual cell sheets harvested from temperature-responsive culture dishes. Stacked cardiomyocyte sheets demonstrated electrical and morphologic communication, resulting in synchronously beating myocardial tissue. When these bioengineered 3D tissue grafts are transplanted onto damaged hearts, gap junction communication between graft and host is likely critical for synchronized beating and functional improvement. In this study, these graft-to-heart morphologic communications were examined.Methods: Neonatal rat cardiomyocyte sheets were harvested from temperature-responsive culture dishes and layered to create 3D tissues. These constructs were then transplanted onto infarcted rat hearts. Histologic analyses and transmission electron microscopy (TEM) were performed to examine morphologic communications. The passage of small molecules through functional gap junctions was also detected using a dye-transfer assay.Results: Transplanted cardiomyocytes bridged between the grafts and hearts in intact areas. Connexin-43 staining and TEM revealed the existence of gap junctions and intercalated disks between the bridging cardiomyocytes. Furthermore, it was confirmed that a low-molecule fluorescent dye, calcein, was transferred from the grafts to the hearts via the bridging cardiomyocytes. Immunohistochemistry with anti-intercellular adhesion molecule-1 antibodies revealed that mesothelial cells in the epicardium scattered and transdifferentiated into mesenchymal cells between the graft and host.Conclusions: The direct attachment of layered cardiomyocyte sheets on the heart surface promotes mesothelial cell transdifferentiation and cardiomyocyte bridging, leading to functional communication via gap junctions. These results indicate that these bioengineered myocardial tissues may improve damaged heart function via synchronized beating.