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El presente artículo quiere establecer los factores que debe conocer los gerentes financieros o directores de empresas para la realización de los procesos de fuentes de financiación de las organizaciones. Se desarrolla bajo tres aspectos: el primero esboza la relación de la financiación con las tres grandes cuentas generadas en el estado de situación financiera. El segundo aspecto presenta el flujo de coordinación entre lo que se financia (costo) y donde se debe invertir la empresa (rentabilidad). Para terminar, se relaciona las decisiones de operación inversión y financiación. El resultado es que el director conozca los factores que inciden en la toma de decisiones en el momento de escoger las fuentes de financiación. Se pretende como fin responder la pregunta de investigación: ¿cuáles son las fuentes de financiación que tiene el CEF en la organización? Este proceso se enmarca en el tipo de investigación cualitativa, con la metodología de revisión documental de los diferentes trabajos académicos propuestos hasta el momento. Para consolidar este documento, se pretenden desarrollar tres grandes objetivos; el primero hace referencia a identificar las diferentes fuentes de financiación dentro de la organización, el segundo objetivo es conocer las fuentes fuera de la organización y como tercer objetivo es establecer los usos mediante la toma de decisiones en las fuentes de financiación. Como resultado principal que se deriva del presente trabajo, es que las personas que se dedican a la administración del recurso financiero conozcan los factores principales internos como externos y busquen la mejor decisión de inversión con el fin de maximizar la rentabilidad de la organización.

Rev.esc.adm.neg El objetivo de este artículo es proponer un nuevo modelo de cambio organizacional o CO basado en teorías contemporáneas que puedan suplir el enfoque de los antiguos modelos de CO, con lo que se pretende desarrollar un nuevo marco conceptual. Se busca que esta propuesta ayude, de manera amplia, a entender las transformaciones y los momentos por los que atraviesan las organizaciones en los procesos de cambio; y que a su vez se convierta en una herramienta que permita ubicar al director ejecutivo en el camino a seguir frente a los posibles escenarios que se puedan presentar en dicho proceso. El modelo, presentado de modo holístico tiene en cuenta los diferentes factores de cambio: individuo-organización-entorno, y sugiere cinco procesos claves: identificación de la estrategia, valor de la organización, personal de la empresa, manejo de la información y evaluación del desempeño; de esta manera, el gerente general puede establecer el anclaje de cambio y, a partir de él, el proceso eficiente en la trasformación de la empresa. Se concluye que el modelo es una nueva alternativa, susceptible a la interpretación, la aplicación, el cuestionamiento y el mejoramiento, que puede convertirse en una herramienta útil para instituciones que están en contextos turbulentos y de incertidumbre, ya que pueden establecer el direccionamiento desde cualquier arista establecida por el modelo sin que sea necesario que se desarrolle en su totalidad, pues lo importante es la capacidad de respuesta rápida.

Zinc finger (ZF), transcription activator-like effectors (TALE), and CRISPR/Cas9 therapies to regulate gene expression are becoming viable strategies to treat genetic disorders, although effective

N-Glycosylations are an important post-translational modification of proteins that can significantly impact cell function. Terminal sialic acid in hybrid or complex N-glycans has been shown to be relevant in various types of cancer, but its role in non-malignant cells remains poorly understood. We have previously shown that the motility of human bone marrow derived mesenchymal stromal cells (MSCs) can be modified by altering N-glycoforms. The goal of this study was to determine the role of sialylated N-glycans in MSCs. Here, we show that IFN-gamma or exposure to culture media low in fetal bovine serum (FBS) increases sialylated N-glycans, while PDGF-BB reduces them. These stimuli alter mRNA levels of sialyltransferases such as ST3Gal1, ST6Gal1, or ST3Gal4, suggesting that sialylation of N-glycans is regulated by transcriptional control of sialyltransferases. We next show that 2,4,7,8,9-pentaacetyl-3Fax-Neu5Ac-CO2Me (3F-Neu5Ac) effectively inhibits sialylations in MSCs. Supplementation with 3F-Neu5Ac increases adhesion and migration of MSCs, as assessed by both videomicroscopy and wound/scratch assays. Interestingly, pre-treatment with 3F-Neu5Ac also increases the survival of MSCs in an in vitro ischemia model. We also show that pre-treatment or continuous treatment with 3F-Neu5Ac inhibits both osteogenic and adipogenic differentiation of MSCs. Finally, secretion of key trophic factors by MSCs is variably affected upon exposure to 3F-Neu5Ac. Altogether, our experiments suggest that sialylation of N-glycans is tightly regulated in response to environmental cues and that glycoengineering MSCs to reduce sialylated N-glycans could be beneficial to increase both cell migration and survival, which may positively impact the therapeutic potential of the cells.

Diabetic foot ulcers are a major health care concern with limited effective therapies. Mesenchymal stem cell (MSC)-based therapies are promising treatment options due to their beneficial effects of immunomodulation, angiogenesis, and other paracrine effects. We investigated whether a bioengineered scaffold device containing hypoxia-preconditioned, allogeneic human MSCs combined with the beta-adrenergic antagonist timolol could improve impaired wound healing in diabetic mice. Different iterations were tested to optimize the primary wound outcome, which was percent of wound epithelialization. MSC preconditioned in 1 μM timolol at 1% oxygen (hypoxia) seeded at a density of 2.5 × 105 cells/cm2 on Integra Matrix Wound Scaffold (MSC/T/H/S) applied to wounds and combined with daily topical timolol applications at 2.9 mM resulted in optimal wound epithelialization 65.6% (24.9% ± 13.0% with MSC/T/H/S vs 41.2% ± 20.1%, in control). Systemic absorption of timolol was below the HPLC limit of quantification, suggesting that with the 7-day treatment, accumulative steady-state timolol concentration is minimal. In the early inflammation stage of healing, the MSC/T/H/S treatment increased CCL2 expression, lowered the pro-inflammatory cytokines IL-1B and IL6 levels, decreased neutrophils by 44.8%, and shifted the macrophage ratio of M2/M1 to 1.9 in the wound, demonstrating an anti-inflammatory benefit. Importantly, expression of the endothelial marker CD31 was increased by 2.5-fold with this treatment. Overall, the combination device successfully improved wound healing and reduced the wound inflammatory response in the diabetic mouse model, suggesting that it could be translated to a therapy for patients with diabetic chronic wounds.

For hundreds of indications, mesenchymal stromal cells (MSCs) have not achieved the expected therapeutic efficacy due to an inability of the cells to reach target tissues. We show that inducing high mannose N-glycans either chemically, using the mannosidase I inhibitor Kifunensine, or genetically, using an shRNA to silence the expression of mannosidase I A1 (MAN1A1), strongly increases the motility of MSCs. We show that treatment of MSCs with Kifunensine increases cell migration toward bone fracture sites after percutaneous injection, and toward lungs after intravenous injection. Mechanistically, high mannose N-glycans reduce the contact area of cells with its substrate. Silencing MAN1A1 also makes cells softer, suggesting that an increase of high mannose N-glycoforms may change the physical properties of the cell membrane. To determine if treatment with Kifunensine is feasible for future clinical studies, we used mass spectrometry to analyze the N-glycan profile of MSCs over time and demonstrate that the effect of Kifunensine is both transitory and at the expense of specific N-glycoforms, including fucosylations. Finally, we also investigated the effect of Kifunensine on cell proliferation, differentiation, and the secretion profile of MSCs. Our results support the notion of inducing high mannose N-glycans in MSCs in order to enhance their migration potential.

Membrane-bound oligosaccharides form the interfacial boundary between the cell and its environment, mediating processes such as adhesion and signaling. These structures can undergo dynamic changes in composition and expression based on cell type, external stimuli, and genetic factors. Glycosylation, therefore, is a promising target of therapeutic interventions for presently incurable forms of advanced cancer. Here, we show that cholangiocarcinoma metastasis is characterized by down-regulation of the Golgi α-mannosidase I coding gene MAN1A1, leading to elevation of extended high-mannose glycans with terminating α-1,2-mannose residues. Subsequent reshaping of the glycome by inhibiting α-mannosidase I resulted in significantly higher migratory and invasive capabilities while masking cell surface mannosylation suppressed metastasis-related phenotypes. Exclusive elucidation of differentially expressed membrane glycoproteins and molecular modeling suggested that extended high-mannose glycosylation at the helical domain of transferrin receptor protein 1 promotes conformational changes that improve noncovalent interaction energies and lead to enhancement of cell migration in metastatic cholangiocarcinoma. The results provide support that α-1,2-mannosylated N-glycans present on cancer cell membrane proteins may serve as therapeutic targets for preventing metastasis.

Mesenchymal stem/stromal cells (MSCs) may be able to improve ischemic conditions as they can actively seek out areas of low oxygen and secrete proangiogenic factors. In more severe trauma and chronic cases, however, cells alone may not be enough. Therefore, we have combined the stem cell and angiogenic factor approaches to make a more potent therapy. We developed an engineered stem cell therapy product designed to treat critical limb ischemia that could also be used in trauma-induced scarring and fibrosis where additional collateral blood flow is needed following damage to and blockage of the primary vessels. We used MSCs from normal human donor marrow and engineered them to produce high levels of the angiogenic factor vascular endothelial growth factor (VEGF). The MSC/VEGF product has been successfully developed and characterized using good manufacturing practice (GMP)-compliant methods, and we have completed experiments showing that MSC/VEGF significantly increased blood flow in the ischemic limb of immune deficient mice, compared to the saline controls in each study. We also performed safety studies demonstrating that the injected product does not cause harm and that the cells remain around the injection site for more than 1 month after hypoxic preconditioning. An on-demand formulation system for delivery of the product to clinical sites that lack cell processing facilities is in development.

Patients with Snyder-Robinson Syndrome (SRS) exhibit deficient Spermidine Synthase (SMS) gene expression, which causes neurodevelopmental defects and osteoporosis, often leading to extremely fragile bones. To determine the underlying mechanism for impaired bone formation, we modelled the disease by silencing SMS in human bone marrow - derived multipotent stromal cells (MSCs) derived from healthy donors. We found that silencing SMS in MSCs led to reduced cell proliferation and deficient bone formation in vitro, as evidenced by reduced mineralization and decreased bone sialoprotein expression. Furthermore, transplantation of MSCs in osteoconductive scaffolds into immune deficient mice shows that silencing SMS also reduces ectopic bone formation in vivo. Tag-Seq Gene Expression Profiling shows that deficient SMS expression causes strong transcriptome changes, especially in genes related to cell proliferation and metabolic functions. Similarly, metabolome analysis by mass spectrometry, shows that silencing SMS strongly impacts glucose metabolism. This was consistent with observations using electron microscopy, where SMS deficient MSCs show high levels of mitochondrial fusion. In line with these findings, SMS deficiency causes a reduction in glucose consumption and increase in lactate secretion. Our data also suggests that SMS deficiency affects iron metabolism in the cells, which we hypothesize is linked to deficient mitochondrial function. Altogether, our studies suggest that SMS deficiency causes strong transcriptomic and metabolic changes in MSCs, which are likely associated with the observed impaired osteogenesis both in vitro and in vivo.

Summary Since hundreds of clinical trials are investigating the use of multipotent stromal cells (MSCs) for therapeutic purposes, effective delivery of the cells to target tissues is critical. We have found an unexplored mechanism, by which basic fibroblast growth factor (FGF2) induces expression of fucosyltransferase 8 (FUT8) to increase core fucosylations of N-linked glycans of membrane-associated proteins, including several integrin subunits. Gain- and loss-of-function experiments show that FUT8 is both necessary and sufficient to induce migration of MSCs. Silencing FUT8 also affects migration of MSCs in zebrafish embryos and a murine bone fracture model. Finally, we use in silico modeling to show that core fucosylations restrict the degrees of freedom of glycans on the integrin’s surface, hence stabilizing glycans on a specific position. Altogether, we show a mechanism whereby FGF2 promotes migration of MSCs by modifying N-glycans. This work may help improve delivery of MSCs in therapeutic settings., Graphical Abstract, Highlights • FGF2 upregulates FUT8 and core fucosylations in MSCs • FUT8 is both necessary and sufficient to promote migration of MSCs • Core fucosylations stabilize the position of N-glycans on integrins, In this article, Fierro and colleagues used RNA-seq and mass spectrometry to find that FGF2 induces migration of MSCs by inducing expression of FUT8, which leads to more core fucosylations of N-linked glycans of membrane-associated proteins, including several integrin subunits. This affects cell migration in zebrafish embryos and toward bone fracture in mice.

En la teoría de las competencias laborales, existen diferentes corrientes que marcan el quehacer administrativo del recurso humano de las organizaciones.En esta propuesta se pretende realizar un análisis de las leyes públicas colombianas en materia que regulan el empleo público, la carrera administrativa entre otros, con las diferentes corrientes existentes, y así, determinar cuál es la orientación de las leyes en el enfoque de competencias laborales.

Patients with Snyder-Robinson Syndrome (SRS) exhibit deficient Spermine Synthase (SMS) gene expression, which causes neurodevelopmental defects and osteoporosis, often leading to extremely fragile bones. To determine the underlying mechanism for impaired bone formation, we modelled the disease by silencing SMS in human bone marrow - derived multipotent stromal cells (MSCs) derived from healthy donors. We found that silencing SMS in MSCs led to reduced cell proliferation and deficient bone formation in vitro, as evidenced by reduced mineralization and decreased bone sialoprotein expression. Furthermore, transplantation of MSCs in osteoconductive scaffolds into immune deficient mice shows that silencing SMS also reduces ectopic bone formation in vivo. Tag-Seq Gene Expression Profiling shows that deficient SMS expression causes strong transcriptome changes, especially in genes related to cell proliferation and metabolic functions. Similarly, metabolome analysis by mass spectrometry, shows that silencing SMS strongly impacts glucose metabolism. This was consistent with observations using electron microscopy, where SMS deficient MSCs show high levels of mitochondrial fusion. In line with these findings, SMS deficiency causes a reduction in glucose consumption and increase in lactate secretion. Our data also suggests that SMS deficiency affects iron metabolism in the cells, which we hypothesize is linked to deficient mitochondrial function. Altogether, our studies suggest that SMS deficiency causes strong transcriptomic and metabolic changes in MSCs, which are likely associated with the observed impaired osteogenesis both in vitro and in vivo.

Background: In vivo amniotic fluid is known to contain a population of mesenchymal stem cells (MSCs) and growth factors and has been shown to assist in healing when used as an adjunct in procedures across multiple medical specialties. It is unclear whether amniotic fluid products (AFPs) contain MSCs and, if so, whether the cells remain viable after processing. Purpose: To determine whether MSCs, growth factors, and hyaluronan are present in commercially available AFPs. Study Design: Descriptive laboratory study. Methods: Seven commercial companies that provide amniotic fluid were invited to participate in the study; 3 companies (the manufacturers of PalinGen, FloGraft, and Genesis AFPs) agreed to participate and donated AFPs for analysis. The AFPs were evaluated for the presence of MSCs, various growth factors relevant to orthopaedics (platelet-derived growth factor ββ, vascular endothelial growth factor, interleukin 8, bone morphogenetic protein 2, transforming growth factor β1), and hyaluronan by enzyme-linked immunosorbent assay and culture of fibroblast colony-forming units. These products were compared with unprocessed amniotic fluid and 2 separate samples of MSCs derived from human bone marrow aspirates. All groups used the same culture medium and expansion techniques. Identical testing and analysis procedures were used for all samples. Results: MSCs could not be identified in the commercial AFPs or the unprocessed amniotic fluid. MSCs could be cultured from the bone marrow aspirates. Nucleated cells were found in 2 products (PalinGen and FloGraft), but most of these cells were dead. The few living cells did not exhibit established characteristics of MSCs. Growth factors and hyaluronan were present in all groups at varying levels. Conclusion: The AFPs studied should not be considered “stem cell” therapies, and researchers should use caution when evaluating commercial claims that products contain stem cells. Given their growth factor content, however, AFPs may still represent a promising tool for orthopaedic treatment. Clinical Relevance: Amniotic fluid has been proposed as an allogenic means for introducing MSCs. This study was unable to confirm that commercial AFPs contain MSCs.

Dentro de los mercados existen varios factores que inciden en el crecimiento y desarrollo de los mismos. En esta propuesta se pretende mostrar la relación entre la organización y su incidencia dentro de las políticas de responsabilidad social empresarial.

Mesenchymal stem cells (MSCs) are an excellent source for numerous cellular therapies due to their simple isolation, low immunogenicity, multipotent differentiation potential and regenerative secretion profile. However, over-expanded MSCs show decreased therapeutic efficacy. This shortcoming may be circumvented by identifying methods that promote self-renewal of MSCs in culture. HMGA2 is a DNA-binding protein that regulates self-renewal in multiple types of stem cells through chromatin remodeling, but its impact on human bone marrow-derived MSCs is not known. Using an isolation method to obtain pure MSCs within 9 days in culture, we show that expression of HMGA2 quickly decreases during early expansion of MSCs, while let-7 microRNAs (which repress HMGA2) are simultaneously increased. Remarkably, we demonstrate that FGF-2, a growth factor commonly used to promote self-renewal in MSCs, rapidly induces HMGA2 expression in a time- and concentration-dependent manner. The signaling pathway involves FGF-2 receptor 1 (FGFR1) and ERK1/2, but acts independent from let-7. By silencing HMGA2 using shRNAs, we demonstrate that HMGA2 is necessary for MSC proliferation. However, we also show that over-expression of HMGA2 does not increase cell proliferation, but rather abrogates the mitogenic effect of FGF-2, possibly through inhibition of FGFR1. In addition, using different methods to assess in vitro differentiation, we show that modulation of HMGA2 inhibits adipogenesis, but does not affect osteogenesis of MSCs. Altogether, our results show that HMGA2 expression is associated with highly proliferating MSCs, is tightly regulated by FGF-2, and is involved in both proliferation and adipogenesis of MSCs. J. Cell. Biochem. 117: 2128-2137, 2016. © 2016 Wiley Periodicals, Inc.

Numerous signaling molecules are altered following nerve injury, serving as a blueprint for drug delivery approaches that promote nerve repair. However, challenges with achieving the appropriate temporal duration of recombinant protein delivery have limited the therapeutic success of this approach. Genetic engineering of mesenchymal stem cells (MSCs) to enhance the secretion of proangiogenic molecules such as vascular endothelial growth factor (VEGF) may provide an alternative. We hypothesized that the administration of VEGF-expressing human MSCs would stimulate neurite outgrowth and proliferation of cell-types involved in neural repair. When cultured with dorsal root ganglion (DRG) explants in vitro, control and VEGF-expressing MSCs (VEGF-MSCs) increased neurite extension and proliferation of Schwann cells (SCs) and endothelial cells, while VEGF-MSCs stimulated significantly greater proliferation of endothelial cells. When embedded within a 3D fibrin matrix, VEGF-MSCs maintained overexpression and expressed detectable levels over 21 days. After transplantation into a murine sciatic nerve injury model, VEGF-MSCs maintained high VEGF levels for 2 weeks. This study provides new insight into the role of VEGF on peripheral nerve injury and the viability of transplanted genetically engineered MSCs. The study aims to provide a framework for future studies with the ultimate goal of developing an improved therapy for nerve repair.

Noncanonical WNT pathways function independently of the β-catenin transcriptional co-activator to regulate diverse morphogenetic and pathogenic processes. Recent studies showed that noncanonical WNTs, such as WNT5A, can signal the degradation of several downstream effectors, thereby modulating these effectors’ cellular activities. The protein domain(s) that mediates the WNT5A-dependent degradation response, however, has not been identified. By coupling protein mutagenesis experiments with a flow cytometry-based degradation reporter assay, we have defined a protein domain in the kinesin superfamily protein KIF26B that is essential for WNT5A-dependent degradation. We found that a human disease-causing KIF26B mutation located at a conserved amino acid within this domain compromises the ability of WNT5A to induce KIF26B degradation. Using pharmacological perturbation, we further uncovered a role of glycogen synthase kinase 3 (GSK3) in WNT5A regulation of KIF26B degradation. Lastly, based on the identification of the WNT5A-responsive domain, we developed a new reporter system that allows for efficient profiling of WNT5A-KIF26B signaling activity in both somatic and stem cells. In conclusion, our study identifies a new protein domain that mediates WNT5A-dependent degradation of KIF26B and provides a new tool for functional characterization of noncanonical WNT5A signaling in cells.

Mesenchymal Stem/stromal Cells (MSCs) may be able to improve ischemic conditions as they can actively seek out areas of low oxygen and secrete pro-angiogenic factors. In more severe trauma and chronic cases, however, cells alone may not be enough. Therefore, we have combined the stem cell and angiogenic factor approaches to make a more potent therapy. We developed an engineered stem cell therapy product designed to treat critical limb ischemia (CLI), that could also be used in trauma-induced scarring and fibrosis where additional collateral bloodflow is needed following damage to and blockage of the primary vessels. We used MSCs from normal human donor bone marrow, and engineered them to produce high levels of the angiogenic factor Vascular Endothelial Growth Factor (VEGF). The MSC/VEGF product has been successfully developed and characterized using Good Manufacturing Practice (GMP) - compliant methods, and we have completed experiments showing that MSC/VEGF significantly increased blood flow in the ischemic limb of immune deficient mice, as compared to the saline controls in each study. We also performed safety studies, demonstrating that the injected product does not cause harm and that the cells remain around the injection site for over a month after hypoxic pre-conditioning. An on-demand formulation system for delivery of the product to clinical sites that lack cell processing facilities is in development.

El artículo destaca los diferentes aspectos de la sociedad (individuo y grupo) dentro de la economía desarrollada por las empresas multinacionales, creando realidades económicas que desde la fenomenología construyen nuevas culturas de compra estandarizadas que permiten perder el control interno de la racionalidad de los individuos y, a su vez, fortalecer la personalidad. El tema se desarrolla en tres partes, la primera se refiere a cómo la fenomenología crea y unifica la cultura del individuo con los mensajes confusos que envían las multinacionales; la segunda se ocupa del mensaje que se difunde respecto al ideal de sociedad y cómo el individuo afecta de manera voluntaria el locus del control interno; y la tercera aborda el fortalecimiento de la identidad individual en el desarrollo del planteamiento del yo, el ello y el super yo.

© 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press In this study, we engineered mesenchymal stem cells (MSCs) to over-express basic fibroblast growth factor (bFGF) and evaluated its effects on fracture healing. Adipose-derived mouse MSCs were transduced to express bFGF and green fluorescence protein (ADSCbFGF-GFP). Closed-femoral fractures were performed with osterix-mCherry reporter mice of both sexes. The mice received 3 × 105ADSCs transfected with control vector or bFGF via intramuscular injection within or around the fracture sites. Mice were euthanized at days 7, 14, and 35 to monitor MSC engraftment, osteogenic differentiation, callus formation, and bone strength. Compared to ADSC culture alone, ADSCbFGFincreased bFGF expression and higher levels of bFGF and vascular endothelial growth factor (VEGF) in the culture supernatant for up to 14 days. ADSCbFGFtreatment increased GFP-labeled MSCs at the fracture gaps and these cells were incorporated into the newly formed callus. quantitative reverse transcription polymerase chain reaction (qRT-PCR) from the callus revealed a 2- to 12-fold increase in the expression of genes associated with nervous system regeneration, angiogenesis, and matrix formation. Compared to the control, ADSCbFGFtreatment increased VEGF expression at the periosteal region of the callus, remodeling of collagen into mineralized callus and bone strength. In summary, MSCbFGFaccelerated fracture healing by increasing the production of growth factors that stimulated angiogenesis and differentiation of MSCs to osteoblasts that formed new bone and accelerated fracture repair. This novel treatment may reduce the time required for fracture healing. Stem Cells Translational Medicine 2017;6:1880–1893.

Bone remodeling is a lifelong process in which mature bone tissue is removed from the skeleton by bone resorption and is replenished by new during ossification or bone formation. The remodeling cycle requires both the differentiation and activation of two cell types with opposing functions; the osteoclast, which orchestrates bone resorption, and the osteoblast, which orchestrates bone formation. The differentiation of these cells from their respective precursors is a process which has been overshadowed by enigma, particularly because the precise osteoclast precursor has not been identified and because the identification of skeletal stem cells, which give rise to osteoblasts, is very recent. Latest advances in the area of stem cell biology have enabled us to gain a better understanding of how these differentiation processes occur in physiological and pathological conditions. In this review we postulate that modulation of stem cells during inflammatory conditions is a necessary prerequisite of bone remodeling and therefore an essential new component to the field of osteoimmunology. In this context, we highlight the role of transcription factor nuclear factor of activated T cells cytoplasmic 1 (NFATc1), because it directly links inflammation with differentiation of osteoclasts and osteoblasts.

Multipotent mesenchymal stromal cells (MSCs) are ideal candidates for different cellular therapies due to their simple isolation, extensive expansion potential, and low immunogenicity. For various therapeutic approaches, such as bone and cartilage repair, MSCs are expected to contribute by direct differentiation to replace the damaged tissue, while many other applications rely on the secretion of paracrine factors which modulate the immune response and promote angiogenesis. MicroRNAs (miRNAs), which target messenger RNA for cleavage or translational repression, have recently been shown to play critical functions in MSC to regulate differentiation, paracrine activity, and other cellular properties such as proliferation, survival, and migration. The global miRNA expression profile of MSC varies according to the tissue of origin, species, and detection methodology, while also certain miRNAs are consistently found in all types of MSC. The function in MSC of more than 60 different miRNAs has been recently described, which is the subject of this review. A special emphasis is given to miRNAs that have demonstrated a function in MSC in vivo. We also present in detail miRNAs with overlapping effects (i.e., common target genes) and discuss future directions to deepen our understanding of miRNA biology in MSC. These recent discoveries have opened the possibility of modulating miRNAs in MSC, in order to enhance their proregenerative, therapeutic potential.

Cuando se realiza el emprendimiento en el país, se utilizan las mismas acciones y metodologías en las diferentes instituciones, sin tener en cuenta la caracterización de las regiones y de las personas. Esto se presenta porque se parte del hecho que los individuos que forman una comunidad poseen la misma forma de pensar y actuar frente a un tema en específico, sin embargo se nota claramente el desarrollo del emprendimiento en unas regiones más que otras.Este fenómeno se puede explicar desde como la fenomenología forma la cultura de los individuos, y esta moldea la personalidad que converge en el desarrollo de competencias, que cambian el contexto del emprendedor, al revisar este fenómeno es importante la formación como eje central. Todos nacemos emprendedores, pero la educación facilita el proceso de cristalizar la idea, sin embargo esta educación debe estar orientada teniendo en cuenta el tipo cultural de la región.

Background Adipose-derived mesenchymal stem cells (ASCs) are a promising cell therapy to treat inflammatory and immune-mediated diseases. Development of appropriate pre-clinical animal models is critical to determine safety and attain early efficacy data for the most promising therapeutic candidates. Naturally occurring diseases in cats already serve as valuable models to inform human clinical trials in oncologic, cardiovascular, and genetic diseases. The objective of this study was to complete a comprehensive side-by-side comparison of human and feline ASCs, with an emphasis on their immunomodulatory capacity and transcriptome. Methods Human and feline ASCs were evaluated for phenotype, immunomodulatory profile, and transcriptome. Additionally, transwells were used to determine the role of cell-cell contact in ASC-mediated inhibition of lymphocyte proliferation in both humans and cats. Results Similar to human ASCs, feline ASCs were highly proliferative at low passages and fit the minimal criteria of multipotent stem cells including a compatible surface protein phenotype, osteogenic capacity, and normal karyotype. Like ASCs from all species, feline ASCs inhibited mitogen-activated lymphocyte proliferation in vitro, with or without direct ASC-lymphocyte contact. Feline ASCs mimic human ASCs in their mediator secretion pattern, including prostaglandin E2, indoleamine 2,3 dioxygenase, transforming growth factor beta, and interleukin-6, all augmented by interferon gamma secretion by lymphocytes. The transcriptome of three unactivated feline ASC lines were highly similar. Functional analysis of the most highly expressed genes highlighted processes including: 1) the regulation of apoptosis; 2) cell adhesion; 3) response to oxidative stress; and 4) regulation of cell differentiation. Finally, feline ASCs had a similar gene expression profile to noninduced human ASCs. Conclusions Findings suggest that feline ASCs modulate lymphocyte proliferation using soluble mediators that mirror the human ASC secretion pattern. Uninduced feline ASCs have similar gene expression profiles to uninduced human ASCs, as revealed by transcriptome analysis. These data will help inform clinical trials using cats with naturally occurring diseases as surrogate models for human clinical trials in the regenerative medicine arena. Electronic supplementary material The online version of this article (doi:10.1186/s13287-017-0528-z) contains supplementary material, which is available to authorized users.

Angiogenesis is the process through which new blood vessels are formed from preexisting ones and plays a critical role in several conditions including embryonic development, tissue repair and disease. Moreover, enhanced therapeutic angiogenesis is a major goal in the field of regenerative medicine and efficient vascularization of artificial tissues and organs is one of the main hindrances in the implementation of tissue engineering approaches, while, on the other hand, inhibition of angiogenesis is a key therapeutic target to inhibit for instance tumor growth. During the last decades, the understanding of cellular and molecular mechanisms involved in this process has been matter of intense research. In this regard, several in vitro and in vivo models have been established to visualize and study migration of endothelial progenitor cells, formation of endothelial tubules and the generation of new vascular networks, while assessing the conditions and treatments that either promote or inhibit such processes. In this review, we address and compare the most commonly used experimental models to study angiogenesis in vitro and in vivo. In particular, we focus on the implementation of the zebrafish (Danio rerio) as a model to study angiogenesis and discuss the advantages and not yet explored possibilities of its use as model organism.

Many therapies using mesenchymal stem cells (MSC) rely on their ability to produce and release paracrine signals with chemotactic and pro-angiogenic activity. These characteristics, however, are mostly studied under standard in vitro culture conditions. In contrast, various novel cell-based therapies imply pre-seeding MSC into bio-artificial scaffolds. Here we describe human bone marrow-derived MSC seeded in Integra matrices, a common type of scaffold for dermal regeneration (SDR). We show and measured the distribution of MSC within the SDR, where cells clearly establish physical interactions with the scaffold, exhibiting constant metabolic activity for at least 15 days. In the SDR, MSC secrete VEGF and SDF-1 and induce transwell migration of CD34+ hematopoietic/endothelial progenitor cells, which is inhibited in the presence of a CXCR4/SDF-1 antagonist. MSC in SDR respond to hypoxia by altering levels of angiogenic signals such as Angiogenin, Serpin-1, uPA and IL-8. Finally, we show that MSC-containing SDR that have been pre-incubated in hypoxia show higher infiltration of endothelial cells after implantation into immune deficient mice. Our data show that MSC are fully functional ex vivo when implanted into SDR. In addition, our results strongly support the notion of hypoxic pre-conditioning MSC-containing SDR, in order to promote angiogenesis in the wounds.

Mesenchymal stem cells (MSCs) have been shown to improve tissue regeneration in several preclinical and clinical trials. These cells have been used in combination with three-dimensional scaffolds as a promising approach in the field of regenerative medicine. We compare the behavior of human adipose-derived MSCs (AdMSCs) on four different biomaterials that are awaiting or have already received FDA approval to determine a suitable regenerative scaffold for delivering these cells to dermal wounds and increasing healing potential. AdMSCs were isolated, characterized, and seeded onto scaffolds based on chitosan, fibrin, bovine collagen, and decellularized porcine dermis.In vitroresults demonstrated that the scaffolds strongly influence key parameters, such as seeding efficiency, cellular distribution, attachment, survival, metabolic activity, and paracrine release. Chick chorioallantoic membrane assays revealed that the scaffold composition similarly influences the angiogenic potential of AdMSCsin vivo. The wound healing potential of scaffolds increases by means of a synergistic relationship between AdMSCs and biomaterial resulting in the release of proangiogenic and cytokine factors, which is currently lacking when a scaffold alone is utilized. Furthermore, the methods used herein can be utilized to test other scaffold materials to increase their wound healing potential with AdMSCs.

Mesenchymal stem cells/multipotent stromal cells (MSCs) are promising therapeutics for a variety of conditions. However, after transplantation, cell retention remains extremely challenging. Given that many hypoxic signals are transitory and that the therapeutic administration of MSCs is typically into tissues that are normally hypoxic, we studied the effect of hypoxic preconditioning (HP) prior to new exposure to hypoxia. We show that preincubation for 2 days or more in 1% oxygen reduces serum deprivation-mediated cell death, as observed by higher cell numbers and lower incorporation of EthD-III and Annexin V. Consistently, HP-MSCs expressed significantly lower levels of cytochrome c and heme oxygenase 1 as compared to controls. Most importantly, HP-MSCs showed enhanced survival in vivo after intramuscular injection into immune deficient NOD/SCID-IL2Rgamma−/− mice. Interestingly, HP-MSCs consume glucose and secrete lactate at a slower rate than controls, possibly promoting cell survival, as glucose remains available to the cells for longer periods of time. In addition, we compared the metabolome of HP-MSCs to controls, before and after hypoxia and serum deprivation, and identified several possible mediators for HP-mediated cell survival. Overall, our findings suggest that preincubation of MSCs for 2 days or more in hypoxia induces metabolic changes that yield higher retention after transplantation. Stem Cells 2015;33:1818–1828

The chemokine CXCL12 regulates the interaction between hematopoietic stem and progenitor cells and bone marrow stromal cells. Although its relevance in the bone marrow niche is well recognized, the regulation of CXCL12 by microRNA is not completely understood. We transfected a library of 486 microRNA in the bone marrow stromal cell line SCP-1 and studied the expression of CXCL12. Twenty-seven microRNA were shown to downregulate expression of CXCL12. Eight microRNA (miR-23a, 130b, 135, 200b, 200c, 216, 222, and 602) interacted directly with the 3′UTR of CXCL12. Next, we determined that only miR-23a is predicted to bind to the 3′UTR and is strongly expressed in primary bone marrow stromal cells. Modulation of miR-23a changes the migratory potential of hematopoietic progenitor cells in co-culture experiments. We discovered that TGFB1 mediates its inhibitory effect on CXCL12 levels by upregulation of miR-23a. This process was partly reversed by miR-23a molecules. Finally, we determined an inverse expression of CXCL12 and miR-23a in stromal cells from patients with myelodys-plastic syndrome indicating that the interaction has a pathophysiological role. Here, we show for the first time that CXCL12-targeting miR23a regulates the functional properties of the hematopoietic niche.

La deficiencia de vitamina B 12 es la causa más frecuente de anemia después del origen ferropénico. Objetivo: establecer el perfil sociodemográfico y clínico en anemia megaloblástica. Materiales y métodos: serie de pacientes hospitalizados con anemia megaloblástica entre enero 2010 y diciembre 2011 en los hospitales de San José e Infantil Universitario de San José, Bogotá DC. Resultados: 17 casos, 11 en hombres. Edad promedio 59 años (DE: 15.8 años, rango: 37-82), 88% casados, estrato dos 76.4%, pensionados 17%, con ingresos de dos salarios mínimos legales vigentes mensuales 94.1% y conviven con más de dos personas 75.4%. Siete pacientes (41.1%) con déficit combinado de ácido fólico y vitamina B12, de vitamina B 12 tres (17.6%) y de ácido fólico dos (14.2%). Las manifestaciones más frecuentes fueron anorexia (70.5%), piel seca (62.5%), glositis atrófica (29,4%) e ictericia (23.5%). Se observó asociación con enfermedad autoinmune en 17.6%, neoplasias de origen no hematológico 11.7% y consumo crónico de alcohol 35.3%. Conclusión: la mayoría pertenecieron a estrato socioeconómico bajo, con ingresos limitados y familias constituidas por más de dos personas. Las manifestaciones más frecuentes fueron digestivas, dermatológicas y neurológicas. Se encontró déficit combinado de vitamina B12 y ácido fólico, exclusivo de ácido fólico asociado con consumo crónico de alcohol y solo de vitamina B 12. Abreviaturas: AM, anemia megaloblástica.

Objective: The oncogene leukemia/lymphoma-related factor (LRF) enhances chondrosarcoma proliferation and malignancy. This study aimed to investigate the roles of LRF in chondrogenic differentiation of primary human bone marrow–derived mesenchymal stem cells (BMSCs). Design: LRF was overexpressed in BMSC by lentiviral transduction. Chondrogenic differentiation of BMSC was induced by high-density pellet culture. Western blotting and real-time polymerase chain reaction were used to investigate changes in protein and mRNA levels, respectively, during chondrogenesis. Safranin-O staining, immunohistochemistry, and glycoaminoglycan contents were used to assess cartilage matrix deposition. BMSC proliferation was determined by mitochondrial dehydrogenase activity and cell counting. Cell cycle profiling was performed by flow cytometry. Results: LRF overexpression effectively inhibited protein and mRNA expression of chondrocyte markers and cartilage matrix deposition during chondrogenesis of BMSC. Endogenous LRF expression was constitutively high in undifferentiated BMSC but remained low in primary articular chondrocytes. Endogenous LRF protein was downregulated in a time-dependent manner during chondrogenesis. BMSCs overexpressing LRF had higher proliferation rates and cell population in the S phase. LRF suppressed p53 expression during chondrogenesis and this might prevent differentiating chondrocytes from entering a quiescent state. Conclusion: Our data showed that LRF is important for stimulating stem cell proliferation and cell cycle progression. It is known that LRF is highly expressed in the mouse limb buds prior to overt chondrogenesis; thus, LRF might function to prevent premature chondrogenic differentiation of stem cells.

Chondrosarcoma is a form of malignant skeletal tumor of cartilaginous origin. The non-malignant form of the disease is termed chondroma. Correctly distinguishing between the two forms is essential for making therapeutic decisions. However, due to their similar histological appearances and the lack of a reliable diagnostic marker, it is often difficult to distinguish benign tumors from low-grade chondrosarcoma. Therefore, it is necessary to search for a potential marker that has diagnostic and prognostic values in chondrosarcoma. In this study, we demonstrated by immunohistochemistry that elevated leukemia/lymphoma-related factor (LRF) expression was associated with increased malignancy in human chondrosarcoma tissue microarrays. Moreover, siRNA depletion of LRF drastically reduced proliferation of chondrosarcoma cell lines and effectively induced senescence in these cells. This could be attributed to the observation that LRF-depleted cells were arrested at the G(1) phase, and had increased p53 and p21 expression. Moreover, LRF depletion not only drastically reduces the cellular migration and invasion potentials of chondrosarcoma cells but also sensitized these cells to the apoptosis-inducing chemotherapeutic agent doxorubicin. We conclude that LRF is a survival factor in chondrosarcomas and its expression correlates with tumor malignancy and chemoresistance. Our data implicate the potential role of LRF as both a diagnostic marker and therapeutic target for chondrosarcomas.

El mundo, en una acepción muy amplia, se debate entre dos corrientes ideológicas que han dado mucho de qué hablar y en la cuales existen más divergencias que acuerdos. Una de ellas es el avance de una economía capitalista avasalladora en la que, a pesar de los presagios de algunos científicos sociales, no se ven cambios significativos actualmente y tampoco se vislumbran en el mediano plazo. Por otra parte, se encuentra el concepto del desarrollo sostenible y su relación con la expresión clásica del capitalismo: los mercados eficientes. El presente artículo propone un modelo de desarrollo sostenible a partir de una revisión teórica de las facetas anteriormente descritas, con el objetivo de que se constituya en un punto de partida de este debate, permita continuar el enriquecimiento del mismo y se propenda por el cuidado del medioambiente desde una perspectiva sistémica donde todos los actores tomen parte activa. El manuscrito partió de la correspondiente revisión de literatura y permitió concluir la importancia del papel del Estado como regulador del medioambiente y la empresa como agente de cambio medioambiental en su compromiso con la producción limpia.

A key mechanism for mesenchymal stem cells/bone marrow stromal cells (MSCs) to promote tissue repair is by secretion of soluble growth factors (GFs). Therefore, clinical application could be optimized by a combination of cell and gene therapies, where MSCs are genetically modified to express higher levels of a specific factor. However, it remains unknown how this overexpression may alter the fate of the MSCs. Here, we show effects of overexpressing the growth factors, such as basic fibroblast growth factor (bFGF), platelet derived growth factor B (PDGF-BB), transforming growth factor β1 (TGF-β1), and vascular endothelial growth factor (VEGF), in human bone marrow-derived MSCs. Ectopic expression of bFGF or PDGF-B lead to highly proliferating MSCs and lead to a robust increase in osteogenesis. In contrast, adipogenesis was strongly inhibited in MSCs overexpressing PDGF-B and only mildly affected in MSCs overexpressing bFGF. Overexpression of TGF-β1 blocked both osteogenic and adipogenic differentiation while inducing the formation of stress fibers and increasing the expression of the smooth muscle marker calponin-1 and the chondrogenic marker collagen type II. In contrast, MSCs overexpressing VEGF did not vary from control MSCs in any parameters, likely due to the lack of VEGF receptor expression on MSCs. MSCs engineered to overexpress VEGF strongly induced the migration of endothelial cells and enhanced blood flow restoration in a xenograft model of hind limb ischemia. These data support the rationale for genetically modifying MSCs to enhance their therapeutically relevant trophic signals, when safety and efficacy can be demonstrated, and when it can be shown that there are no unwanted effects on their proliferation and differentiation.

Mesenchymal stem cells (MSCs) have been shown to contribute to the recovery of tissues through homing to injured areas, especially to hypoxic, apoptotic, or inflamed areas and releasing factors that hasten endogenous repair. In some cases genetic engineering of the MSC is desired, since they are excellent delivery vehicles. We have derived MSCs from the human embryonic stem cell (hESC) line H9 (H9-MSCs). They expressed CD105, CD90, CD73, and CD146, and lacked expression of CD45, CD34, CD14, CD31, and HLA-DR, the hESC pluripotency markers SSEA-4 and Tra-1-81, and the hESC early differentiation marker SSEA-1. Marrow-derived MSCs showed a similar phenotype. H9-MSCs did not form teratoma in our initial studies, whereas the parent H9 line did so robustly. H9-MSCs differentiated into bone, cartilage, and adipocytes in vitro, and displayed increased migration under hypoxic conditions. Finally, using a hindlimb ischemia model, H9-MSCs were shown to home to the hypoxic muscle, but not the contralateral limb, by 48 h after IV injection. In summary, we have defined methods for differentiation of hESCs into MSCs and have defined their characteristics and in vivo migratory properties.

Background Hematopoietic stem cells located in the bone marrow interact with a specific microenvironment referred to as the stem cell niche. Data derived from ex vivo co-culture systems using mesenchymal stromal cells as a feeder cell layer suggest that cell-to-cell contact has a significant impact on the expansion, migratory potential and ‘stemness’ of hematopoietic stem cells. Here we investigated in detail the spatial relationship between hematopoietic stem cells and mesenchymal stromal cells during ex vivo expansion. Design and Methods In the co-culture system, we defined three distinct localizations of hematopoietic stem cells relative to the mesenchymal stromal cell layer: (i) those in supernatant (non-adherent cells); (ii) those adhering to the surface of mesenchymal stromal cells (phase-bright cells) and (iii) those beneath the mesenchymal stromal cells (phase-dim cells). Cell cycle, proliferation, cell division and immunophenotype of these three cell fractions were evaluated from day 1 to 7. Results Phase-bright cells contained the highest proportion of cycling progenitors during co-culture. In contrast, phase-dim cells divided much more slowly and retained a more immature phenotype compared to the other cell fractions. The phase-dim compartment was soon enriched for CD34+/CD38− cells. Migration beneath the mesenchymal stromal cell layer could be hampered by inhibiting integrin β1 or CXCR4. Conclusions Our data suggest that the mesenchymal stromal cell surface is the predominant site of proliferation of hematopoietic stem cells, whereas the compartment beneath the mesenchymal stromal cell layer seems to mimic the stem cell niche for more immature cells. The SDF-1/CXCR4 interaction and integrin-mediated cell adhesion play important roles in the distribution of hematopoietic stem cells in the co-culture system.

Objective The Notch signaling pathway has been shown to play a role in bone marrow−derived stromal cell differentiation, however, the precise outcome of Notch activation remains controversial. The aim of this study was to evaluate the effect of Notch signaling in primary human bone marrow−derived stromal cells (hBMSCs). Materials and Methods hBMSCs were transduced to >90% with lentiviral vectors containing either human notch1 intracellular domain ( NICD ), jagged1 , or dominant negative mastermind1 . Cells were exposed to adipogenic and osteogenic differentiation stimuli and differentiation was quantified by oil red or alizarin red staining, alkaline phosphatase liver/bone/kidney (ALPL) activity and expression of adipogenic or osteogenic marker genes. Results NICD and jagged1 transgene−expressing hBMSCs demonstrated enhanced mineralization, nodule formation, and ALPL activity in osteogenic differentiation media. These findings correlated with increased gene expression of bone morphogenetic protein 2 and ALPL . In contrast, NICD or jagged1 transgene expression strongly inhibited adipocyte formation and reduced peroxisome proliferator-activated receptor-γ , fatty acid binding protein 4 , and adiponectin precursor gene expression. Co-overexpression of dominant negative mastermind1 and NICD or jagged1 led to a partial rescue of the differentiation phenotypes. In addition, high endogenous jagged1 expression levels were observed in hBMSCs samples with strong ALPL activity compared to a group of samples with low ALPL activity. Conclusion In summary, our data suggest that induction of Notch signaling enhances the osteogenic differentiation of hBMSCs while inhibiting the adipogenic fate.

Objectives: Recent data show that Imatinib mesylate (IM) also affects haematopoietic stem cells (HSC), T lymphocytes and dendritic cells that do not harbour constitutively active tyrosine kinases. Materials and methods: We evaluated possible effects of IM on human bone marrow‐derived mesenchymal stem cells (MSC) in vitro. Results: Screening the activity of 42 receptor tyrosine kinases revealed an exclusive inhibition of platelet‐derived growth factor receptorβ (PDGFRβ). Analysis of downstream targets of PDGFRβ demonstrated IM‐mediated reduction of Akt and Erk1/2 phosphorylation. Culture of MSC with IM led to the reversible development of perinuclear multi‐vesicular bodies. The proliferation and clonogenicity of MSC were significantly reduced compared to control cultures. IM favoured adipogenic differentiation of MSC whereas osteogenesis was suppressed. The functional deficits described led to a 50% reduction in the support of clonogenic haematopoietic stem cells, cultured for 1 month on a monolayer of MSC with IM. Conclusion: In summary, inhibition of PDGFRβ and downstream Akt and Erk signalling by IM has a significant impact on proliferation and differentiation of human MSC in vitro.

RESUMENEl propósito de la investigación fue estudiar los prejuicios y errores en la toma de decisiones y su relación con los modelos racionales en 16 empresas de servicios seleccionadas a juicio de los investigadores en los departamentos de Tolima y Huila, Colombia. Se trató de un estudio mixto quea través del análisis multidimensional, permitió establecer que en estas organizaciones prevalecen los enfoques intuitivos sobre los formales en sus procesos decisionales. Igualmente se evidenciaroncorrelaciones significativas e independencia entre estas variables.Palabras clave: toma de decisiones, decisiones estratégicas, racionalidad, racionalidad limitada,métodos para la toma de decisiones, incertidumbre.The heuristic and the decision making in services companiesABSTRACTThe purpose of this research was to study the prejudices and mistakes in decision making and your relation with the rational models in 6 enterprises of services selected to judgment of the investigators on the departments of Tolima and Huila, Colombia. It was a combined study which through of multivariate analysis, allowed to establish that in these organizations prevail the intuitive approaches over that the formals in their decision making process. Equally significant correlations between these variables and independence were evident.Keywords: decisions making, strategic decisions, heuristic, rationality, bounded rationality, methodsmaking decisions, uncertainty.Heurística e a toma de decisão em empresas de serviços.RESUMOO objetivo da pesquisa foi estudar os preconceitos e erros na toma de decisões e sua relação com os modelos racionais em 16 empresas de serviços, selecionadas segundo o parecer dos pesquisadores dosdepartamentos de Tolima e Huila, na Colômbia. Este foi um estudo misto que a través da análise multidimensional, permitiu estabelecer que nestas organizações prevalecem os enfoques intuitivos por sobre os formais em seus processos de toma de decisão. Da mesma forma, se evidenciaram correlações significativas e independência entre estas variáveis.Palavras-chave: toma de decisões, decisões estratégicas, racionalidade, racionalidade limitada,métodos de toma de decisão, incerteza.

Over 240 clinical trials are in progress worldwide using mesenchymal stem cells (MSCs). Some critical advantages of MSCs include simple isolation and expansion, and ease for allogeneic applications due to their immune evading properties. MSCs produce many paracrine signals that promote tissue regeneration, though at sub-therapeutic levels. We have therefore developed a product that combines cell and gene therapy, by engineering MSCs to overexpress vascular endothelial growth factor (VEGF). Here we show our preclinical data that not only confirms the efficacy of our product (MSC-VEGF), but addresses multiple safety aspects. Here, MSCs are transduced with a GMP-grade lentiviral vector to obtain an average of one copy per cell (ranging from 0.8 to 1.3), minimizing occurrence of insertional mutagenesis. The secretion of VEGF is optimized by using a previously clinically evaluated constitutive promoter (MNDU3) and an enhancer element acting in cis (WPRE). Safety studies at this level of secretion (approx. 80pg/ml VEGF secreted per 1000 cells per 24 hours) did not cause edema or hemangiomas in immune deficient NOD/SCID IL-2R-gnull/null (NSG) mice. The genomic stability of MSC-VEGF was addressed by karyotyping analysis, where no abnormalities were found in MSCs transduced with increasing viral loads, and by PCR to evaluate potential genomic rearrangement of the insert. To rule out tumorigenicity of MSC-VEGF, cells transduced with increased viral load were in injected into NSG mice. In contrast to 3 distinct positive controls used, no tumors were detected in over 50 mice treated with MSC-VEGF up to 6 months after injection. Additional safety studies included confirmation by flow cytometry of homogeneity of the transduction level of MSC-VEGF, absence of replication competent lentivirus, freedom of endotoxin, mycoplasma and absence VSV-G viral envelope coding plasmid. Luciferase-expressing MSC-VEGF consistently decreased to undetectable levels by 28 days after injection and PCR confirmed the absence of human DNA 6 months after injection. Pilot efficacy studies using MSC-VEGF in an immune deficient mouse model of hind limb ischemia (HLI) have been completed. MSC-VEGF were injected IM the day after HLI surgery into the ischemic limbs of NSG mice and blood flow was monitored weekly, demonstrating that MSC-VEGF treatment leads to faster revascularization than control treatment. Furthermore, we show that a small percentage of injected MSC-VEGF take a pericyte position on blood vessels. While future assays are intended as IND-enabling safety studies, these pre-clinical safety and efficacy studies are directed towards our planned Phase I clinical trial.

Ex vivo cultures of human bone marrow-derived mesenchymal stem cells (MSCs) contain subsets of progenitors exhibiting dissimilar properties. One of these subsets comprises uncommitted progenitors displaying distinctive features, such as morphology, a quiescent condition, growth factor production, and restricted tissue biodistribution after transplantation. In this study, we assessed the competence of these cells to express, in the absence of differentiation stimuli, markers of mesoderm and ectodermic (neural) cell lineages. Fluorescence microscopy analysis showed a unique pattern of expression of osteogenic, chondrogenic, muscle, and neural markers. The depicted "molecular signature" of these early uncommitted progenitors, in the absence of differentiation stimuli, is consistent with their multipotentiality and plasticity as suggested by several in vitro and in vivo studies.