Potential mesenchymal stem cell therapy for skin diseases

Enhanced healing of a full-thickness wound by a thermoresponsive dressing utilized for simultaneous transfer and protection of adipose-derived mesenchymal stem cells sheet

To boost the healing process in a full-thickness wound, a simple and efficient strategy based on adipose-derived mesenchymal stem cells (ADSCs) transplantation is described in this work. To increase the chance of ADSCs immobilization in the wound bed and prevent its migration, these cells are fully grown on the surface of a thermoresponsive dressing membrane under in vitro condition. Then, the cells sheet with their secreted extracellular matrix (ECM) is transferred to the damaged skin with the help of this dressing membrane. This membrane remains on wound bed and acts both as a cell sheet transfer vehicle, after external reduction of temperature, and protect wound during the healing process like a common wound dressing. The visual inspection of wounded skin (rat animal model) at selected time intervals shows a higher wound closure rate for ADSCs treated group. For this group of rats, the better quality of reconstructed tissue is approved by results of histological and immunohistochemical analysis since the higher length of the new epidermis, the higher thickness of re-epithelialization layer, a higher level of neovascularization and capillary density, and the least collagen deposition are detected in the healed tissue.

High porous electrospun poly(ε-caprolactone)/gelatin/MgO scaffolds preseeded with endometrial stem cells promote tissue regeneration in full-thickness skin wounds: An in vivo study

In the current study, electrospun poly(ε-caprolactone)-gelatin (PCL-Gel) fibrous scaffolds containing magnesium oxide (MgO) particles and preseeded with human endometrial stem cells (hEnSCs) were developed to use as wound care material in skin tissue engineering applications. Electrospun fibers were fabricated using PCL-Gel (1:1 [wt/wt]) with different concentrations of MgO particles (1, 2, and 4 wt%). The fibrous scaffolds were evaluated regarding their microstructure, mechanical properties, surface wettability, and in vitro and in vivo performances. The full-thickness excisional wound model was used to evaluate the in vivo wound healing ability of the fabricated scaffolds. Our findings confirmed that the wounds covered with PCL-Gel fibrous scaffolds containing 2 wt% MgO and preseeded with hEnSCs have nearly 79% wound closure ability while sterile gauze showed 11% of wound size reduction. Our results can be employed for biomaterials aimed at the healing of full-thickness skin wounds.

Encapsulation of curcumin loaded chitosan nanoparticle within poly (ε-caprolactone) and gelatin fiber mat for wound healing and layered dermal reconstitution

Hybrid electrospun fiber containing bioactive molecules, which offer the ability to deliver the cells into the wound bed, will help to achieve a high therapeutic effect. In this study, an electrospun polycaperlactone (PCL) and gelatin (Gela) scaffold containing curcumin loaded chitosan nanoparticle (NCs/Cur) was used to evaluate in vivo wound healing ability of the fabricated scaffolds. The electrospun hybrid scaffold seeded with human endometrial stem cells (EnSCs) showed desirable biocompatibility with the host immune system and wound healing ability in a full-thickness excisional animal model. The constructs were characterized for structural, mechanical and biochemical properties. Fourier transform infrared spectroscopy (FTIR) confirmed all typical absorption characteristics of PCL and Gela polymers as well as NCs and Cur. The results showed the perfect contact angle, wettability and degradability of hybrid fiber scaffolds with the good mechanical and structural characteristics including shape uniformity, pore size and porosity. The cell attachment and proliferation on the PCL/Gela/NCs/Cur was higher than PCL and PCL/Gela scaffolds. In term of the capability of hybrid scaffold and EnSCs in histological analysis, this novel tissue-engineered construct could be suggested as a skin substitute to repair injured skin and regenerative medicine application.

Cellular Internalization-Induced Aggregation of Porous Silicon Nanoparticles for Ultrasound Imaging and Protein-Mediated Protection of Stem Cells

Nanotechnology employs multifunctional engineered materials in the nanoscale range that provides many opportunities for translational stem cell research and therapy. Here, a cell-penetrating peptide (virus-1 transactivator of transcription)-conjugated, porous silicon nanoparticle (TPSi NP) loaded with the Wnt3a protein to increase both the cell survival rate and the delivery precision of stem cell transplantation via a combinational theranostic strategy is presented. The TPSi NP with a pore size of 10.7 nm and inorganic framework enables high-efficiency loading of Wnt3a, prolongs Wnt3a release, and increases antioxidative stress activity in the labeled mesenchymal stem cells (MSCs), which are highly beneficial properties for cell protection in stem cell therapy for myocardial infarction. It is confirmed that the intracellular aggregation of TPSi NPs can highly amplify the acoustic scattering of the labeled MSCs, resulting in a 2.3-fold increase in the ultrasound (US) signal compared with that of unlabeled MSCs. The translational potential of the designed nanoagent for real-time US imaging-guided stem cell transplantation is confirmed via intramyocardial injection of labeled MSCs in a nude mouse model. It is proposed that the intracellular aggregation of protein drug-loaded TPSi NPs could be a simple but robust strategy for improving the therapeutic effect of stem cell therapy.

Effects of mesenchymal stem cell therapy on alopecia areata in cellular and hair follicle organ culture models

Mesenchymal stem cell therapy (MSCT) has been suggested as a new therapeutic strategy for immunological disorders. There have been only a few attempts to treat alopecia areata (AA) with MSCT. MSCT efficacy and mechanism of action in treating AA are not known. We sought to investigate the effect of human hematopoietic mesenchymal stem cells (hHMSCs) on an in vitro model of AA and to explore relevant mechanisms that regulate efficacy. An AA-like environment was induced by pretreatment of human dermal papilla cells (hDPCs) with interferon gamma (IFN-γ). hHMSCs were administered to the hDPCs, and cell viability was determined. Similar studies were also conducted with human hair follicles (HFs) in culture. The change in expression of the Wnt/β-catenin pathway and JAK/STAT pathway-related molecules and growth factors in hHMSC-treated hDPCs was also examined by reverse transcription-PCR, Western blot assay and growth factor array. Immune privilege-related molecules were examined by immunohistochemistry in HF culture models. hHMSCs enhanced the cell viability of the hDPCs. hHMSCs activated several molecules in the Wnt/β-catenin signalling pathway, including ß-catenin and phosphorylated GSK3b, and decreased IFN-γ-induced expression of DKK1 in hDPCs. hHMSCs suppressed IFN-γ-induced expression of caspase-1, caspase-3 and IFN-γ receptor. hHMSCs induced the phosphorylation of STAT1 and STAT3 compared to controls and IFN-γ-pretreated hDPCs. hHMSC-treated HFs enhanced several growth factor mRNAs. hHMSC pretreatment modulated IFN-γ-induced expression of molecules related to HF immune privilege on HFs in organ culture. These data suggest MSCT may be a new potential therapeutic option in treating AA.

Collagen-coated nano-electrospun PCL seeded with human endometrial stem cells for skin tissue engineering applications

Human endometrial stem cells (hEnSCs) are known as an attractive source of stem cells for regenerative medicine. hEnSCs are easily isolated and are capable of repairing uterine through their strong ability of creating new capillaries. In this study, a three-dimensional (3D) nanofibrous polycaprolactone (PCL)/collagen scaffold was fabricated and characterized in order to be applied as a new approach for skin reconstruction. Furthermore, the behavior of hEnSCs on this scaffold was investigated. First, a PCL 3D scaffold was constructed using electrospinning technique. Plasma treated and PCL was grafted by collagen. The constructs were characterized for mechanical and structural properties. Cell attachment, proliferation, viability, and differentiation of hEnSCs were assessed after being seeded on PCL and PCL/collagen scaffolds using scanning electron microscopy, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and real-time polymerase chain reaction tests. The results showed higher wettability for the PCL/collagen scaffold with desirable mechanical and structural characteristics compared to PCL and collagen alone. The attachment and proliferation rates of hEnSCs on the PCL/collagen scaffold were higher compared to those on the bare PCL. Hence, hEnSCs are newly discovered stem cell source for skin tissue engineering in vitro, particularly when developed on PCL/collagen nanofiber scaffolds. Therefore, application of hEnSCs for skin regeneration is a novel therapeutic approach for temporary skin substitute. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1578-1586, 2018.

Immunomodulatory oligonucleotide IMT504: Effects on mesenchymal stem cells as a first-in-class immunoprotective/immunoregenerative therapy

The immune responses of humans and animals to insults (i.e., infections, traumas, tumoral transformation and radiation) are based on an intricate network of cells and chemical messengers. Abnormally high inflammation immediately after insult or abnormally prolonged pro-inflammatory stimuli bringing about chronic inflammation can lead to life-threatening or severely debilitating diseases. Mesenchymal stem cell (MSC) transplant has proved to be an effective therapy in preclinical studies which evaluated a vast diversity of inflammatory conditions. MSCs lead to resolution of inflammation, preparation for regeneration and actual regeneration, and then ultimate return to normal baseline or homeostasis. However, in clinical trials of transplanted MSCs, the expectations of great medical benefit have not yet been fulfilled. As a practical alternative to MSC transplant, a synthetic drug with the capacity to boost endogenous MSC expansion and/or activation may also be effective. Regarding this, IMT504, the prototype of a major class of immunomodulatory oligonucleotides, induces in vivo expansion of MSCs, resulting in a marked improvement in preclinical models of neuropathic pain, osteoporosis, diabetes and sepsis. IMT504 is easily manufactured and has an excellent preclinical safety record. In the small number of patients studied thus far, IMT504 has been well-tolerated, even at very high dosage. Further clinical investigation is necessary to demonstrate the utility of IMT504 for resolution of inflammation and regeneration in a broad array of human diseases that would likely benefit from an immunoprotective/immunoregenerative therapy.

Multidisciplinary approaches to stimulate wound healing

New civil wars and waves of terrorism are causing crucial social changes, with consequences in all fields, including health care. In particular, skin injuries are evolving as an epidemic issue. From a physiological standpoint, although wound repair takes place more rapidly in the skin than in other tissues, it is still a complex organ to reconstruct. Genetic and clinical variables, such as diabetes, smoking, and inflammatory/immunological pathologies, are also important risk factors limiting the regenerative potential of many therapeutic applications. Therefore, optimization of current clinical strategies is critical. Here, we summarize the current state of the field by focusing on stem cell therapy applications in wound healing, with an emphasis on current clinical approaches being developed. These involve protocols for the ex vivo expansion of adipose tissue-derived mesenchymal stem cells by means of a patented Good Manufacturing Practice-compliant platelet lysate. Combinations of multiple strategies, including genetic modifications and stem cells, biomimetic scaffolds, and novel vehicles, such as nanoparticles, are also discussed as future approaches.

Mesenchymal stem cell therapy for immune-modulation: the donor, the recipient, and the drugs in-between

Adoptive transfer of cultured bone marrow stromal cells (mesenchymal stem cells also known as MSCs) is a promising new way to aid tissue regeneration and treat a wide variety of diseases where regulation of inflammatory responses is derailed. Although significant advances have been made in the field, pinpointing important mechanistic details about how MSCs function in vitro and in vivo, there are still many unanswered questions that need to be addressed before welcoming MSCs in the therapeutic arsenal of immune mediated diseases. In this viewpoint, we highlight and discuss a few factors that we believe are critical in terms of therapeutic success employing cultured MSCs. Selecting the right donor population, choosing the best culture conditions and picking the patient population that is most likely to give a favourable therapeutic response is just as important as considering interactions between MSCs and the combination of drugs in the recipient's body. Given the complexity of MSC-host interactions, it is also imperative to develop screening tools that account for as many variables as possible and predict precisely the in vivo response rates before MSCs enter the body. To achieve this, a multidisciplinary approach is required with comprehensive knowledge of basic MSC biology, immunology, pharmacology and good clinical practice.