A Simple Method to Produce Engineered Cartilage from Human Adipose-Derived Mesenchymal Stem Cells and Poly ε-Caprolactone Scaffolds

INTRODUCTION

The damaged articular cartilage has limited self-regeneration capacity because of the absence of blood vessels, lymphatics, and nerves. Cartilage transplantation is, hence, a popular method used to treat this disease. However, sources of autograft and allogenic cartilage for transplantation are limited. Therefore, this study aims to suggest a simple method to produce engineered cartilage from human adipose-derived mesenchymal stem cells (ADSCs) and poly (ε-caprolactone) (PCL) scaffolds.

METHODS

ADSCs were isolated and expanded from fat tissues according to published protocols. PCL-porous scaffolds were produced from PCL with 5 × 5 × 0.6 mm3 with 200-400 μ m pore sizes. ADSCs were seeded on the PCL scaffolds at three different densities (104, 105, 106 cells per scaffold). The adherence of ADSCs on the surface of PCL scaffolds was evaluated based on an immunostaining assay to determine the presence of ADSCs. The cell proliferation on PCL scaffolds was determined by MTT assay. The complexity in ADSCs and PCL scaffolds was induced to cartilage using a chondrogenesis medium. The engineered cartilage was characterized by the accumulation of proteoglycan and aggrecan by Safranin O staining assay. Their structures were evaluated using an H-E staining assay. Finally, these engineered cartilage tissues were transplanted into mice to assess cartilage maturation when compared to natural cartilage.

RESULTS

The results showed that the engineered cartilage tissues could be successfully produced by cultures of ADSCs on poly ε-caprolactone scaffolds in combination with chondrogenesis medium. The suitable density of ADSCs was 106 cells/per scaffold of 5 × 6 × 0.6 mm3 with pore size from 200 to 400 μ m.

CONCLUSION

The results showed that an in vitro cartilage tissue was created from ADSCs and PCL scaffold. The cartilage tissue exists in the mice for 6 months.

Selective Cytotoxicity of Some Plant Extracts Against Hepatocellular Carcinoma Cells but Not Mesenchymal Stem Cells: A Pilot Screening

INTRODUCTION

Medicinal plants have been used for disease treatment throughout history, especially in Asia. Vietnam is a tropical country which possesses forests with a diversity of plants; among the plants, many have been historically used as alternative therapies for various disease treatments. In this study we aimed to evaluate the selective cytotoxicity of some plant extracts (collected from Vietnamese forests) against hepatocellular carcinoma cells HepG2, compared to adipose tissue-derived mesenchymal stem cells (ADSCs).

METHODS

In this study, we collected nine plants and produced nine extracts from them; these included whole stem of Buchanania lucida, whole stem of Dipterocarpus turbinatus, Hopea recopei, whole stem of Shorea thorelii, bark of Shorea thorelii stem, bark of Dipterocarpus turbinatus stem, whole stem of Dipterocarpus costatus, bark of Dipterocarpus costatus stem, and rhizome of Boesenbergia pandurata. The cytotoxicity of these extracts on hepatocellular carcinoma cells and mesenchymal stem cells were determined based on IC₅₀ values calculated using Alamar Blue assay. Based on these IC₅₀ values, the side effect index (SEI) of extracts was determined. Only the extracts with low SEI were used in further assays to determine the apoptotic status of both hepatocellular carcinoma cells and mesenchymal stem cells via caspase 3/7 induction assay, nuclei disintegration (using Hoechst 33342 staining), and Annexin V staining assay.

RESULTS

The results showed that B. pandurata extract had strong cytotoxicity toward HepG2 cells with lowest side index on mesenchymal stem cells (IC₅₀ on HepG2 of 222 ± 27.82 (μg/ml) but IC₅₀ on ADSCs of 382 ± 16.19 (μg/ml)). Nuclear staining showed that B. pandurata extract could induce disintegration of cell nuclei at the concentration of 400 μg/ml. After 3 h of incubation with B. pandurata extract at the concentration of 200 μg/ml, the BP extract induced caspase 3/7 activation in HepG2 cells, but not in mesenchymal stem cells. Annexin V staining showed that the BP extract induced apoptosis in HepG2 cells in a dose-dependent manner.

CONCLUSION

This study revealed that selective cytotoxicity of some extracts on cancer cells could be determined based on their IC₅₀ values on cancer cells and on mesenchymal stem cells. B. pandurata extract displayed the lowest side effect index on mesenchymal stem cells and successfully induced apoptosis in hepatocellular carcinoma cells HepG2 via activation of caspase 3/7.

Comparison of intraoperative procedures for isolation of clinical grade stromal vascular fraction for regenerative purposes: a systematic review

Intraoperative application of the stromal vascular fraction (SVF) of adipose tissue requires a fast and efficient isolation procedure of adipose tissue. This review was performed to systematically assess and compare procedures currently used for the intraoperative isolation of cellular SVF (cSVF) and tissue SVF (tSVF) that still contain the extracellular matrix. Pubmed, EMBASE and the Cochrane central register of controlled trials databases were searched for studies that compare procedures for intraoperative isolation of SVF (searched 28 September 2016). Outcomes of interest were cell yield, viability of cells, composition of SVF, duration, cost and procedure characteristics. Procedures were subdivided into procedures resulting in a cSVF or tSVF. Thirteen out of 3038 studies, evaluating 18 intraoperative isolation procedures, were considered eligible. In general, cSVF and tSVF intraoperative isolation procedures had similar cell yield, cell viability and SVF composition compared to a nonintraoperative (i.e. culture laboratory-based collagenase protocol) control group within the same studies. The majority of intraoperative isolation procedures are less time consuming than nonintraoperative control groups, however. Intraoperative isolation procedures are less time-consuming than nonintraoperative control groups with similar cell yield, viability of cells and composition of SVF, and therefore more suitable for use in the clinic. Nevertheless, none of the intraoperative isolation procedures could be designated as the preferred procedure to isolate SVF. Copyright © 2017 John Wiley & Sons, Ltd.

Production of endothelial progenitor cells from skin fibroblasts by direct reprogramming for clinical usages

Endothelial progenitor cells (EPCs) play an important role in angiogenesis. However, they exist in limited numbers in the human body. This study was aimed to produce EPCs, for autologous transplantation, using direct reprogramming of skin fibroblasts under GMP-compliant conditions. Fibroblasts were collected and cultured from the skin in DMEM/F12 medium supplemented with 5% activated platelet-rich plasma and 1% antibiotic-antimycotic solution. They were then transfected with mRNA ETV2 and incubated in culture medium under hypoxia (5% oxygen) for 14 d. Phenotype analysis of transfected cells confirmed that single-factor ETV2 transfection successfully reprogrammed dermal fibroblasts into functional EPCs. Our results showed that ETV2 mRNA combined with hypoxia can give rise to functional EPCs. The cells exhibited functional phenotypes similar to endothelial cells derived from umbilical cord vein; they expressed CD31 and VEGFR2, and formed capillary-like structures in vitro. Moreover, these EPCs could significantly improve hindlimb ischemia in mouse models. Although the direct conversion efficacy was low (3.12 ± 0.98%), altogether our study demonstrates that functional EPCs can be produced from fibroblasts and can be used in clinical applications.