Cell Biology International Immediate Publications

Isolation and characterization of lung resident mesenchymal stem cells capable of differentiating into alveolar epithelial type II cells

X Gong, Z Sun, D Cui, X Xu, H Zhu, L Wang, W Qian, X Han — 2012-08-28T15:04:38Z

In recent years, more and more controversies and risks have been reported about the exogenous mesenchymal stem cells-based therapies. In contrast with employing exogenous stem cell, making use of lung resident mesenchymal stem cells (LR-MSCs) should be advantageous. Therefore, the purpose of our study is to isolate the LR-MSCs and explore their potential to differentiate into alveolar epithelial type II cells (ATII cells). In this work, the total lung cells were first precultured, then the Sca-1⁺CD45^-CD31^-population was purified using fluorescence activated cell sorting (FACS). With this methods, we suggested that the Sca-1⁺CD45^-CD31^-cells were LR-MSCs. Similar to bone marrow derived mesenchymal stem cells (BM-MSCs), these cells expressed Sca-1, CD29, CD90, CD44 and CD106, but not CD31 or CD45; shared the same gene expression file with the BM-MSCs; had a similar DNA content to the BM-MSCs during a long-term culturing; and could be serially passaged with all the properties maintained. Above all, the LR-MSCs could differentiate into ATII cells when co-cultured with ATII cells in the trans-well system. Conclusively, these findings demonstrated that the Sca-1⁺CD45^-CD31^- cells appeared to be LR-MSCs and could differentiate into ATII cells. This approach may hold promise in using LR-MSC for treatment in lung disease.

Epigenetic control of TNAP expression in Pseudoxanthoma elasticum fibroblasts

A Ostuni, V Infantino, A Salvia, R Miglionico, F Boraldi, G Annovi, F Bisaccia — 2012-01-26T14:15:52Z

Progressive calcification and fragmentation of elastic fibers are characteristic hallmarks of Pseudoxanthoma elasticum (PXE) which is caused by mutations in the ABCC6 gene encoding the multidrug resistance-associated protein 6 (MRP6). Several evidences suggested that PXE is a metabolic disorder but the exact mechanism by which ABCC6 mutations promote the elastic fiber mineralization is unknown. To shed light in this issue, we analyzed, by real-time PCR, the expression profile of a number of genes involved in matrix gla-protein (MGP) γ-carboxylation and in phosphate generation, in healthy and PXE dermal fibroblasts. Tissue nonspecific alkaline phosphatase (TNAP), NADPH: P450 reductase (P450R) and Protein Disulphyde Isomerase (PDIA2) mRNAs showed meaningfull quantitative differences in PXE fibroblasts with respect to the control cells. In order to verify whether epigenetic events can regulate the expression of genes involved in the PXE phenotype, we investigated DNA methylation and hystone acetylation status of TNAP and PDIA2. Our results demonstrate that in vivo methylation of TNAP promoter is inversely correlated with the gene expression level. Moreover, TNAP expression in PXE fibroblasts is susceptible to the methylation status of promoter, while, in healthy fibroblasts, some other control mechanism prevails.

Humanised substitutes for animal sera in human mesenchymal stem cell culture and differentiation

2011-04-15T09:27:47Z

The use of animal sera in cell culture is a major deterrent for using such cells in cellular therapy owing to potential contamination with xenogenic agents. This necessitates the development of ‘humanized’ supplements to overcome such problems. This study investigates the use of two ‘human-derived’ supplements, namely human platelet lysate (hPL) and umbilical cord blood serum (UCBS), in human mesenchymal stem cell (hMSCs) culture. Properties of hMSCs cultured in either of these supplements including growth kinetics and the differentiation potential were better than those cultured in animal sera-supplemented media. This is also the first report concerning hepatogenic differentiation of hMSCs cultured in UCBS-supplemented media. Development of ‘humanized’ alternatives to FBS could be revolutionary in terms of extrapolating results from in-vitro cultured / expanded hMSCs to direct clinical cellular therapeutic strategies.

Controlling the in vitro differentiation of embryonic stem cells for myocardial tissue engineering applications

D Ou, R Chen, X Liu, J Guo, H Wang, Q Zheng — 2009-09-15T15:09:57Z

We studied the differentiation of embryonic stem cells (ESCs) and developed a novel protocol for generating functional cardiomyocytes (CMs) from ESCs by co-culturing these with live cardiac cells. We then evaluated the structural and functional properties of these ESC-derived CMs (ESCMs). An acellular matrix obtained from rabbit heart tissues was used as a scaffold. Then ESCMs were seeded onto the acellular matrix for preliminary tissue engineering applications. We found that by mimicking the cardiac microenvironment, the percentage of beating embryoid bodies (EBs) was much higher and the homogeneity of EBs were significantly improved over that seen in the control group (p<0.001). ESCMs in EBs acquired almost the same structural and functional properties as typical CMs. After implantation, the cells in the EBs rapidly grew and expanded in the extracellular matrix. These results indicate that the differentiation of ESCs can be controlled in a cardiac mimicking microenvironment and that ESCs can be used as an ideal cell source for large-scale tissue engineering applications for the procurement of cardiac muscle.