Stem cells translational medicine
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Stem Cells Transl Med · Jan 2016
Role of Keratinocyte Growth Factor in the Differentiation of Sweat Gland-Like Cells From Human Umbilical Cord-Derived Mesenchymal Stem Cells.
Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have higher proliferation potency and lower immune resistance than human bone marrow MSCs and can differentiate into various functional cells. Many regulatory factors, including keratinocyte growth factor (KGF), are involved in the development of skin and cutaneous appendages. Although KGF is important in wound healing, the role of KGF in hUC-MSC differentiation remains unknown. In our previous work, we found the mixing medium (nine parts of basic sweat-gland [SG] medium plus one part of conditioned heat-shock SG medium) could induce hUC-MSC differentiation to sweat gland-like cells (SGCs). In this study, we further improved the inducing medium and determined the effects of KGF in hUC-MSC differentiation. We found KGF expression in the SGCs and that recombinant human KGF could induce hUC-MSC differentiation into SGCs, suggesting KGF plays a pivotal role in promoting hUC-MSC differentiation to SGCs. Furthermore, the SGCs differentiated from hUC-MSCs were applied to severely burned skin of the paw of an in vivo severe combined immunodeficiency mouse burn model. Burned paws treated with SGCs could regenerate functional sparse SGs 21 days after treatment; the untreated control paws could not. Collectively, these results demonstrated that KGF is a critical growth factor for SGC differentiation from hUC-MSCs and the differentiated SGCs from hUC-MSCs may have a potential therapeutic application for regeneration of destroyed SGs and injured skin. ⋯ There is growing evidence demonstrating a potential therapeutic application of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in injured skin. In the current study, conditioned media and chemically defined media with recombinant human keratinocyte growth factor (KGF) could induce hUC-MSC differentiation into sweat gland-like cells (SGCs). Moreover, the differentiated SGCs from hUC-MSCs could regenerate functional sparse sweat glands in a mouse burn model, which provides further insight into the mechanisms of the role of KGF and a potential therapeutic application of differentiated SGCs for regeneration of destroyed sweat glands and injured skin.
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Stem Cells Transl Med · Jan 2016
Naïve Induced Pluripotent Stem Cells Generated From β-Thalassemia Fibroblasts Allow Efficient Gene Correction With CRISPR/Cas9.
Conventional primed human embryonic stem cells and induced pluripotent stem cells (iPSCs) exhibit molecular and biological characteristics distinct from pluripotent stem cells in the naïve state. Although naïve pluripotent stem cells show much higher levels of self-renewal ability and multidifferentiation capacity, it is unknown whether naïve iPSCs can be generated directly from patient somatic cells and will be superior to primed iPSCs. In the present study, we used an established 5i/L/FA system to directly reprogram fibroblasts of a patient with β-thalassemia into transgene-free naïve iPSCs with molecular signatures of ground-state pluripotency. Furthermore, these naïve iPSCs can efficiently produce cross-species chimeras. Importantly, using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease genome editing system, these naïve iPSCs exhibit significantly improved gene-correction efficiencies compared with the corresponding primed iPSCs. Furthermore, human naïve iPSCs could be directly generated from noninvasively collected urinary cells, which are easily acquired and thus represent an excellent cell resource for further clinical trials. Therefore, our findings demonstrate the feasibility and superiority of using patient-specific iPSCs in the naïve state for disease modeling, gene editing, and future clinical therapy. ⋯ In the present study, transgene-free naïve induced pluripotent stem cells (iPSCs) directly converted from the fibroblasts of a patient with β-thalassemia in a defined culture system were generated. These naïve iPSCs, which show ground-state pluripotency, exhibited significantly improved single-cell cloning ability, recovery capacity, and gene-targeting efficiency compared with conventional primed iPSCs. These results provide an improved strategy for personalized treatment of genetic diseases such as β-thalassemia.
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Stem Cells Transl Med · Jan 2016
Propranolol and Mesenchymal Stromal Cells Combine to Treat Traumatic Brain Injury.
More than 6.5 million patients are burdened by the physical, cognitive, and psychosocial deficits associated with traumatic brain injury (TBI) in the U.S. Despite extensive efforts to develop neuroprotective therapies for this devastating disorder, there have been no successful outcomes in human clinical trials to date. Retrospective studies have shown that β-adrenergic receptor blockers, specifically propranolol, significantly decrease mortality of TBI through mechanisms not yet fully elucidated but are thought to counterbalance a hyperadrenergic state resulting from a TBI. Conversely, cellular therapies have been shown to improve long-term behavior following TBI, likely by reducing inflammation. Given the nonredundancy in their therapeutic mechanisms, we hypothesized that a combination of acute propranolol followed by mesenchymal stem cells (MSCs) isolated from human bone marrow would have additive effects in treating a rodent model of TBI. We have found that the treatments are well-tolerated individually and in combination with no adverse events. MSCs decrease BBB permeability at 96 hours after injury, inhibit a significant accumulation of activated microglia/macrophage in the thalamic region of the brain both short and long term, and enhance neurogenesis short term. Propranolol decreases edema and reduces the number of fully activated microglia at 7 days and the number of semiactivated microglia at 120 days. Combinatory treatment improved cognitive and memory functions 120 days following TBI. Therefore, the results here suggest a new, efficacious sequential treatment for TBI may be achieved using the β-blocker propranolol followed by MSC treatment. ⋯ Despite continuous efforts, traumatic brain injury (TBI) remains the leading cause of death and disability worldwide in patients under the age of 44. In this study, an animal model of moderate-severe TBI was treated with an acute dose of propranolol followed by a delayed dose of human mesenchymal stem cells (MSCs), resulting in improved short- and long-term measurements. These results have direct translational application. They reinforce the inevitable clinical trial of MSCs to treat TBI by demonstrating, among other benefits, a notable decrease in chronic neuroinflammation. More importantly, these results demonstrate that MSCs and propranolol, which is increasingly being used clinically for TBI, are compatible treatments that improve overall outcome.