徐放性DDSと未分化細胞を用いた脳虚血に対する再生医療の基礎的研究

科学研究費助成事業 研究成果報告書：基盤研究(C)2015-2017課題番号 : 15K1029

Preliminary in vivo magnetofection data using magnetic calcium phosphate nanoparticles immobilizing DNA and iron oxide nanocrystals

The data reported herein are in association with our research article entitled "Rapid one-pot fabrication of magnetic calcium phosphate nanoparticles immobilizing DNA and iron oxide nanocrystals using injection solutions for magnetofection and magnetic targeting" (Shubhra et al. 2017) [1]. This article reports morphological and gene delivery (in vitro and preliminary in vivo) data of those calcium phosphate (CaP) naonparticles (NPs) with various iron oxide (IO) contents, named as CaP-Fe(1), CaP-Fe(2), CaP-Fe(3), CaP-Fe(4), and CaP-Fe(5), which were prepared via coprecipitation in supersaturated CaP solutions with nominal Fe concentrations 6.97, 13.94, 27.87, 55.74, and 139.35 μg/mL, respectively. Morphological data of four different NPs: CaP-Fe(1), CaP-Fe(2), CaP-Fe(4), and CaP-Fe(5) are shown here. Data of the luciferase reporter gene expression assay show the effects of the coprecipitation time and the dosage of the CaP-Fe(3) NPs on gene expression levels of CHO-K1 cells transfected by the NPs without external magnetic field. It is demonstrated using digital and microscopic images that the CaP-Fe(3) NPs localize near the periphery of the external magnet that was placed under the cell culture plate. Using the CaP-Fe(3) NPs, animal experiments were conducted to obtain preliminary in vivo magnetofection data

Application of liposomes incorporating doxorubicin with sialyl Lewis X to prevent stenosis after rat carotid artery injury

Restenosis remains a serious complication that can occur after angioplasty. This study investigated the efficiency of an active targeting chemotherapy using liposomes, including doxorubicin, whose surface was decorated with sialyl Lewis X (SLX) (Dox-Lipo-SLX) to prevent stenosis after angioplasty. Its delivery was controlled via the affinity between SLX and E-selectin proteins, which are expressed on vessel walls with injury. In vitro experiments confirmed the accumulation of doxorubicin as a consequence of Dox-Lipo-SLX adhering to E-selectin-positive cells. Significant doxorubicin accumulation was observed on injured vessel walls in rats treated with Dox-Lipo-SLX. In contrast, there was little accumulation using free doxorubicin or a liposome containing doxorubicin (Dox-Lipo), but without SLX. Rats were assigned to one of four groups: Dox-Lipo-SLX, Dox-Lipo, free doxorubicin, or no treatment. Dox-Lipo-SLX, Dox-Lipo, and free doxorubicin, including a dose of 0.08 mg/kg doxorubicin, were intravenously administered three times in each group after angioplasty. The residual lumen area of rats in the group treated with Dox-Lipo-SLX was significantly larger than those in all other groups. These results demonstrate that an active targeting drug delivery system utilizing Dox-Lipo-SLX effectively prevents stenosis after angioplasty

A subpopulation of endothelial progenitor cells with low aldehyde dehydrogenase activity attenuates acute ischemic brain injury in rats

Previous studies have examined the therapeutic effect of endothelial progenitor cells (EPCs) during the chronic phase of cerebral infarction in rats; however, few studies have investigated the effects of EPCs during the acute phase of infarction. In this study, we evaluated the therapeutic effect of EPCs with low aldehyde dehydrogenase activity (Alde-Low EPCs) in rats with acute cerebral infarction, and our results provide insight that may help to identify a therapeutic mechanism of EPCs for acute cerebral infarction. The administration of Alde-Low EPCs into rats with acute cerebral infarction results in the accumulation and migration of the Alde-Low EPCs into the infarct area and the subsequent decrease of infarct volume. Moreover, we found that the stromal cell-derived factor-1 (SDF-1) and CXC chemokine receptor 4 (CXCR4) signaling pathway may regulate the accumulation of Alde-Low EPCs. The transplantation of Alde-Low EPCs may represent a potential treatment strategy for acute cerebral infarction

Area-Specific Cell Stimulation via Surface-Mediated Gene Transfer Using Apatite-Based Composite Layers

Surface-mediated gene transfer systems using biocompatible calcium phosphate (CaP)-based composite layers have attracted attention as a tool for controlling cell behaviors. In the present study we aimed to demonstrate the potential of CaP-based composite layers to mediate area-specific dual gene transfer and to stimulate cells on an area-by-area basis in the same well. For this purpose we prepared two pairs of DNA–fibronectin–apatite composite (DF-Ap) layers using a pair of reporter genes and pair of differentiation factor genes. The results of the area-specific dual gene transfer successfully demonstrated that the cells cultured on a pair of DF-Ap layers that were adjacently placed in the same well showed specific gene expression patterns depending on the gene that was immobilized in theunderlying layer. Moreover, preliminary real-time PCR results indicated that multipotential C3H10T1/2 cells may have a potential to change into different types of cells depending on the differentiation factor gene that was immobilized in the underlying layer, even in the same well. Because DF-Ap layers have a potential to mediate area-specific cell stimulation on their surfaces, they could be useful in tissue engineering applications