Efficacy of stem cell secretome loaded in hyaluronate sponge for topical treatment of psoriasis.

Psoriasis vulgaris is an inflammatory disease characterized by distinctive skin lesions and dysregulated angiogenesis. Recent research uses stem cell secretion products (CM); a set of bioactive factors with therapeutic properties that regulate several cellular processes, including tissue repair and angiogenesis. The aim of this work was to evaluate the effect of CM of Wharton's gelatin MSC (hWJCM) in a treatment based on the bioactivation of a hyaluronic acid matrix (HA hWJCM) in a psoriasiform-like dermatitis (PD) mouse model. A preclinical study was conducted on PD mice. The effect of hWJCM, Clobetasol (Clob) gold standard, HA Ctrl, and HA hWJCM was tested topically evaluating severity of PD, mice weight as well as skin, liver, and spleen appearance. Treatment with either hWJCM, HA Ctrl or HA hWJCM, resulted in significant improvement of the PD phenotype. Moreover, treatment with HA hWJCM reduced the Psoriasis Area Severity Index (PASI), aberrant angiogenesis, and discomfort associated with the disease, leading to total recovery of body weight. We suggest that the topical application of HA hWJCM can be an effective noninvasive therapeutic solution for psoriasis, in addition to other skin diseases, laying the groundwork for future studies in human patients.

Directed sibling donor cord blood donation in the Chilean Public Health System. / Donación dirigida de sangre de Cordón Umbilical de Hermano Compatible en el Sistema de Salud Público de Chile.

INTRODUCTION: Cord blood (CB) as a source of Hematopoietic Stem Cells for Transplantation (HSCT) is well established. Worldwide, nonetheless, less than 10% of the CB HSCTs are performed with a match sibling donor. Since 2004, the Chilean National Childhood Cancer Program (PINDA) net work, has established a CB directed donation program for HSCT. PATIENTS AND METHOD: An obser vational, descriptive and retrospective study was designed to assess the number and characteristics of the CB units collected in the program as well as the number, clinical characteristics and follow-up of the patients who received an HSCT from those CB units between January 2004 and October 2018. RESULTS: Sixty CB units have been collected; 55 of them with full records and stored. The median volume collected was 74.8 ml (30.0-170.8), the median number of total nucleated cells was 7.6 x 10e8 (2.0-21.1), and the median of CD34+ cells was 1.6 x 10e6 (0.2-11.6). Four high-risk leukemia patients received HSCT, all of them developed severe complications after transplantation and one patient died due to relapse. Those patients currently alive have a 100% Karnofsky/Lansky score. The median follow-up time was 8 years. CONCLUSION: The PINDA program has allowed 4 patients to be transplan ted who otherwise would not have had access to a donor. This directed donation program could be seen as a model for the development of a public cord blood bank in Chile.

Donación dirigida de sangre de Cordón Umbilical de Hermano Compatible en el Sistema de Salud Público de Chile / Directed sibling donor cord blood donation in the Chilean Public Health System

Resumen: Introducción: La sangre de cordón umbilical (SCU) como fuente para trasplante de células proge- nitoras hematopoyéticas (TPH) está bien establecida. Internacionalmente, menos del 10% de los TPH de SCU corresponde a donantes hermanos compatibles. Dentro de la red del Programa Infantil Nacional de Drogas Antineoplásicas (PINDA), existe desde enero 2004 un programa de donación dirigida de SCU para TPH. Pacientes y Método: Se diseñó un estudio observacional, retrospectivo, descriptivo, se revisaron el número y características de las unidades de SCU recolectadas en el PINDA y el número, características y evolución de los pacientes trasplantados con esas unidades entre enero de 2004 y octubre de 2018. Resultados: Sesenta unidades de SCU han sido recolectadas, de ellas 55 con registro completo. La mediana de volumen de las unidades almacenadas fue 74,8 ml (30,0-170,8), la mediana de células nucleadas totales 7,6 x 10e8 (2,0-21,1), mediana de células CD34+ 1,6 x 10e6 (0,2-11,6). Cuatro pacientes con leucemias de alto riesgo fueron trasplantados; mediana de segui miento es de 8 años. Todos desarrollaron complicaciones severas post TPH, uno de ellos falleció de recaída y los tres actualmente vivos presentan un Karnofsky/Lansky 100%. Conclusión: El programa ha permitido el trasplante de 4 pacientes que de otro modo no habrían tenido acceso a un donante. Este programa de donación dirigida puede ser considerado una primera etapa para el desarrollo de un banco público de sangre de cordón umbilical en Chile.

Abstract: Introduction: Cord blood (CB) as a source of Hematopoietic Stem Cells for Transplantation (HSCT) is well established. Worldwide, nonetheless, less than 10% of the CB HSCTs are performed with a match sibling donor. Since 2004, the Chilean National Childhood Cancer Program (PINDA) net work, has established a CB directed donation program for HSCT. Patients and Method: An obser vational, descriptive and retrospective study was designed to assess the number and characteristics of the CB units collected in the program as well as the number, clinical characteristics and follow-up of the patients who received an HSCT from those CB units between January 2004 and October 2018. Results: Sixty CB units have been collected; 55 of them with full records and stored. The median volume collected was 74.8 ml (30.0-170.8), the median number of total nucleated cells was 7.6 x 10e8 (2.0-21.1), and the median of CD34+ cells was 1.6 x 10e6 (0.2-11.6). Four high-risk leukemia patients received HSCT, all of them developed severe complications after transplantation and one patient died due to relapse. Those patients currently alive have a 100% Karnofsky/Lansky score. The median follow-up time was 8 years. Conclusion: The PINDA program has allowed 4 patients to be transplan ted who otherwise would not have had access to a donor. This directed donation program could be seen as a model for the development of a public cord blood bank in Chile.

Downregulation of the Netrin-1 Receptor UNC5b Underlies Increased Placental Angiogenesis in Human Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is a common metabolic disorder, defined by high blood glucose levels during pregnancy, which affects foetal and post-natal development. However, the cellular and molecular mechanisms of this detrimental condition are still poorly understood. A dysregulation in circulating angiogenic trophic factors, due to a dysfunction of the feto-placental unit, has been proposed to underlie GDM. But even the detailed study of canonical pro-angiogenic factors like vascular endothelial growth factor (VEGF) or basic Fibroblast Growth Factor (bFGF) has not been able to fully explain this detrimental condition during pregnancy. Netrins are non-canonical angiogenic ligands produced by the stroma have shown to be important in placental angiogenesis. In order to address the potential role of Netrin signalling in GDM, we tested the effect of Netrin-1, the most investigated member of the family, produced by Wharton's Jelly Mesenchymal Stem Cells (WJ-MSC), on Human Umbilical Vein Endothelial Cells (HUVEC) angiogenesis. WJ-MSC and HUVEC primary cell cultures from either healthy or GDM pregnancies were exposed to physiological (5 mM) or high (25 mM) d-glucose. Our results reveal that Netrin-1 is secreted by WJ-MSC from healthy and GDM and both expression and secretion of the ligand do not change with distinct experimental glucose conditions. Noteworthy, the expression of its anti-angiogenic receptor UNC5b is reduced in GDM HUVEC compared with its expression in healthy HUVEC, accounting for an increased Netrin-1 signalling in these cells. Consistently, in healthy HUVEC, UNC5b overexpression induces cell retraction of the sprouting phenotype.

Hyperbaric Oxygen Increases Stem Cell Proliferation, Angiogenesis and Wound-Healing Ability of WJ-MSCs in Diabetic Mice.

Hyperbaric oxygen therapy (HBOT) is effective for the medical treatment of diverse diseases, infections, and tissue injury. In fact, in recent years there is growing evidence on the beneficial effect of HBOT on non-healing ischemic wounds. However, there is still yet discussion on how this treatment could benefit from combination with regenerative medicine strategies. Here we analyzed the effects of HBOT on three specific aspects of tissue growth, maintenance, and regeneration: (i) modulation of adult rodent (Mus musculus) intestinal stem cell turnover rates; (ii) angiogenesis dynamics during the development of the chorio-allantoic membrane (CAM) in Gallus gallus embryos; (iii) and wound-healing in a spontaneous type II diabetic mouse model with a low capacity to regenerate skin. To analyze these aspects of tissue growth, maintenance, and regeneration, we used HBOT alone or in combination with cellular therapy. Specifically, Wharton Jelly Mesenchymal Stem cells (WJ-MSC) were embedded in a commercial collagen-scaffold. HBOT did not affect the metabolic rate of adult mice nor of chicken embryos. Notwithstanding, HBOT modified the proliferation rate of stem cells in the mice small intestinal crypts, increased angiogenesis in the CAM, and improved wound-healing and tissue repair in diabetic mice. Moreover, our study demonstrates that combining stem cell therapy and HBOT has a collaborative effect on wound-healing. In summary, our data underscore the importance of oxygen tension as a regulator of stem cell biology and support the potential use of oxygenation in clinical treatments.

Runt-Related Transcription Factor 2 Induction During Differentiation of Wharton's Jelly Mesenchymal Stem Cells to Osteoblasts Is Regulated by Jumonji AT-Rich Interactive Domain 1B Histone Demethylase.

Novel bone regeneration approaches aim to obtain immature osteoblasts from somatic stem cells. Umbilical cord Wharton's jelly mesenchymal stem cells (WJ-MSCs) are an ideal source for cell therapy. Hence, the study of mechanisms involved in WJ-MSC osteoblastic differentiation is crucial to exploit their developmental capacity. Here, we have assessed epigenetic control of the Runt-related transcription factor 2 (RUNX2) osteogenic master regulator gene in WJ-MSC. We present evidence indicating that modulation of RUNX2 expression through preventing Jumonji AT-rich interactive domain 1B (JARID1B) histone demethylase activity is relevant to enhance WJ-MSC osteoblastic potential. Hence, JARID1B loss of function in WJ-MSC results in increased RUNX2/p57 expression. Our data highlight JARID1B activity as a novel target to modulate WJ-MSC osteoblastic differentiation with potential applications in bone tissue engineering. Stem Cells 2017;35:2430-2441.

Netrin-1 acts as a non-canonical angiogenic factor produced by human Wharton's jelly mesenchymal stem cells (WJ-MSC).

BACKGROUND: Angiogenesis, the process in which new blood vessels are formed from preexisting ones, is highly dependent on the presence of classical angiogenic factors. Recent evidence suggests that axonal guidance proteins and their receptors can also act as angiogenic regulators. Netrin, a family of laminin-like proteins, specifically Netrin-1 and 4, act via DCC/Neogenin-1 and UNC5 class of receptors to promote or inhibit angiogenesis, depending on the physiological context. METHODS: Mesenchymal stem cells secrete a broad set of classical angiogenic factors. However, little is known about the expression of non-canonical angiogenic factors such as Netrin-1. The aim was to characterize the possible secretion of Netrin ligands by Wharton's jelly-derived mesenchymal stem cells (WJ-MSC). We evaluated if Netrin-1 presence in the conditioned media from these cells was capable of inducing angiogenesis both in vitro and in vivo, using human umbilical vein endothelial cells (HUVEC) and chicken chorioallantoic membrane (CAM), respectively. In addition, we investigated if the RhoA/ROCK pathway is responsible for the integration of Netrin signaling to control vessel formation. RESULTS: The paracrine angiogenic effect of the WJ-MSC-conditioned media is mediated at least in part by Netrin-1 given that pharmacological blockage of Netrin-1 in WJ-MSC resulted in diminished angiogenesis on HUVEC. When HUVEC were stimulated with exogenous Netrin-1 assayed at physiological concentrations (10-200 ng/mL), endothelial vascular migration occurred in a concentration-dependent manner. In line with our determination of Netrin-1 present in WJ-MSC-conditioned media we were able to obtain endothelial tubule formation even in the pg/mL range. Through CAM assays we validated that WJ-MSC-secreted Netrin-1 promotes an increased angiogenesis in vivo. Netrin-1, secreted by WJ-MSC, might mediate its angiogenic effect through specific cell surface receptors on the endothelium, such as UNC5b and/or integrin α6ß1, expressed in HUVEC. However, the angiogenic response of Netrin-1 seems not to be mediated through the RhoA/ROCK pathway. CONCLUSIONS: Thus, here we show that stromal production of Netrin-1 is a critical component of the vascular regulatory machinery. This signaling event may have deep implications in the modulation of several processes related to a number of diseases where angiogenesis plays a key role in vascular homeostasis.

Epigenetic Signatures at the RUNX2-P1 and Sp7 Gene Promoters Control Osteogenic Lineage Commitment of Umbilical Cord-Derived Mesenchymal Stem Cells.

Wharton's Jelly mesenchymal stem cells (WJ-MSCs) are an attractive potential source of multipotent stem cells for bone tissue replacement therapies. However, the molecular mechanisms involved in their osteogenic conversion are poorly understood. Particularly, epigenetic control operating at the promoter regions of the two master regulators of the osteogenic program, RUNX2/P57 and SP7 has not yet been described in WJ-MSCs. Via quantitative PCR profiling and chromatin immunoprecipitation (ChIP) studies, here we analyze the ability of WJ-MSCs to engage osteoblast lineage. In undifferentiated WJ-MSCs, RUNX2/P57 P1, and SP7 promoters are found deprived of significant levels of the histone post-translational marks that are normally associated with transcriptionally active genes (H3ac, H3K27ac, and H3K4me3). Moreover, the RUNX2 P1 promoter lacks two relevant histone repressive marks (H3K9me3 and H3K27me3). Importantly, RUNX2 P1 promoter is found highly enriched in the H3K4me1 mark, which has been shown recently to mediate gene repression of key regulatory genes. Upon induction of WJ-MSCs osteogenic differentiation, we found that RUNX2/P57, but not SP7 gene expression is strongly activated, in a process that is accompanied by enrichment of activating histone marks (H3K4me3, H3ac, and H3K27ac) at the P1 promoter region. Histone mark analysis showed that SP7 gene promoter is robustly enriched in epigenetic repressive marks that may explain its poor transcriptional response to osteoblast differentiating media. Together, these results point to critical regulatory steps during epigenetic control of WJ-MSCs osteogenic lineage commitment that are relevant for future applications in regenerative medicine. J. Cell. Physiol. 232: 2519-2527, 2017. © 2016 Wiley Periodicals, Inc.