Intravenous Infusion of Human Adipose Tissue-Derived Mesenchymal Stem Cells to Treat Type 1 Diabetic Mellitus in Mice: An Evaluation of Grafted Cell Doses.

Mesenchymal stem cell (MSC) transplantation is a novel treatment for diabetes mellitus, especially type 1 diabetes. Many recent publications have demonstrated the efficacy of MSC transplantation on reducing blood glucose and increasing insulin production in both preclinical and clinical trials. However, the investigation of grafted cell doses has been lacking. Therefore, this study aimed to evaluate the different doses of MSCs on treatment of type 1 diabetes in mouse models. MSCs were isolated and expanded from human adipose tissue. Streptozotocin (STZ)-induced diabetic mice were divided into two groups that were intravenously transfused with two different doses of human MSCs: 106 or 2.106 cells/mouse. After transplantation, both grafted and placebo mice were monitored weekly for their blood glucose levels, glucose and insulin tolerance, pancreatic structural changes, and insulin production for 56 days after transplantation. The results showed that the higher dose of MSCs (2.106 cells/mouse) remarkably reduced death rate. The death rates were 50%, 66%, and 0% in placebo group, low-dose (1.106 MSCs) group, and high-dose (2.106 MSCs) group, respectively, after 56 days of treatment. Moreover, blood glucose levels were lower for the high-dose group compared to other groups. Glucose and insulin tolerance, as well as insulin production, were significantly improved in mice transplanted with 2.106 cells. The histochemical analyses also support these results. Thus, a higher (e.g., 2.106) dose of MSCs may be an effective dose for treatment of type 1 diabetes mellitus.

Good manufacturing practice-compliant isolation and culture of human umbilical cord blood-derived mesenchymal stem cells.

BACKGROUND: Mesenchymal stem cells (MSCs) are an attractive source of stem cells for clinical applications. These cells exhibit a multilineage differentiation potential and strong capacity for immune modulation. Thus, MSCs are widely used in cell therapy, tissue engineering, and immunotherapy. Because of important advantages, umbilical cord blood-derived MSCs (UCB-MSCs) have attracted interest for some time. However, the applications of UCB-MSCs are limited by the small number of recoverable UCB-MSCs and fetal bovine serum (FBS)-dependent expansion methods. Hence, this study aimed to establish a xenogenic and allogeneic supplement-free expansion protocol. METHODS: UCB was collected to prepare activated platelet-rich plasma (aPRP) and mononuclear cells (MNCs). aPRP was applied as a supplement in Iscove modified Dulbecco medium (IMDM) together with antibiotics. MNCs were cultured in complete IMDM with four concentrations of aPRP (2, 5, 7, or 10%) or 10% FBS as the control. The efficiency of the protocols was evaluated in terms of the number of adherent cells and their expansion, the percentage of successfully isolated cells in the primary culture, surface marker expression, and in vitro differentiation potential following expansion. RESULTS: The results showed that primary cultures with complete medium containing 10% aPRP exhibited the highest success, whereas expansion in complete medium containing 5% aPRP was suitable. UCB-MSCs isolated using this protocol maintained their immunophenotypes, multilineage differentiation potential, and did not form tumors when injected at a high dose into athymic nude mice. CONCLUSION: This technique provides a method to obtain UCB-MSCs compliant with good manufacturing practices for clinical application.

In vitro evaluation of the effects of human umbilical cord extracts on human fibroblasts, keratinocytes, and melanocytes.

Skin aging is the result of internal and external factors. So-called photoaging has been identified as the major factor in skin aging. Effects of photoaging include inhibition of fibroblast and keratinocyte proliferation as well as collagen and fibronectin expression, while activating expression of collagenases such as matrix metalloproteinase-1. Previous studies have shown that extracts or products from human placenta significantly improve skin aging and chronic wound healing. However, there are few studies of umbilical cord extracts. Therefore, this study aimed to evaluate the effects of umbilical cord extract-derived formulae on three kinds of skin cells including fibroblasts, keratinocytes, and melanocytes. We prepared 20 formulae from intracellular umbilical cord extracts, extracellular umbilical cord extracts, and umbilical cord-derived stem cell extracts, as well as five control formulae. We evaluated the effects of the 25 formulae on fibroblast and keratinocyte proliferation, and expression of collagen I, fibronectin, and matrix metalloproteinase-1 in fibroblasts and tyrosinase in melanocytes. The results showed that 7.5% formula 35 was the most effective formula for promotion of fibroblast and keratinocyte proliferation. At this concentration, formula 35 also induced collagen expression and inhibited matrix metalloproteinase-1 expression at the transcriptional level. However, this formula had no effect on tyrosinase expression in melanocytes. These results demonstrate that umbilical cord extracts can serve as an attractive source of proteins for skincare and chronic wound healing products.