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1.
Int J Stem Cells ; 9(2): 192-206, 2016 Nov 30.
Article de Anglais | MEDLINE | ID: mdl-27871152

RÉSUMÉ

BACKGROUND AND OBJECTIVES: Idiopathic pulmonary fibrosis (IPF) is a progressive, irreversible, invariably fatal fibrotic lung disease with no lasting option for therapy. Mesenchymal stem cells (MSCs) could be a promising modality for the treatment of IPF. Aim of the study was to investigate improvement in survivability and anti-fibrotic efficacy of human adipose-derived mesenchymal stem cells (AD-MSCs) in comparison with pirfenidone in the bleomycin-induced pulmonary fibrosis model. METHODS: Human AD-MSCs were administered intravenously on day 3, 6 and 9 after an intra-tracheal challenge with bleomycin, whereas, pirfenidone was given orally in drinking water at the rate of 100 mg/kg body weight three times a day daily from day 3 onward. AD-MSCs were labelled with PKH-67 before administration to detect engraftment. Disease severity and improvement was assessed and compared between sham control and vehicle control groups using Kaplan-Meier survival analysis, biochemical and molecular analysis, histopathology and high resolution computed tomography (HRCT) parameters at the end of study. RESULTS: Results demonstrated that AD-MSCs significantly increase survivability; reduce organ weight and collagen deposition better than pirfenidone group. Histological analyses and HRCT of the lung revealed that AD-MSCs afforded protection against bleomycin induced fibrosis and protect architecture of the lung. Gene expression analysis revealed that AD-MSCs potently suppressed pro-fibrotic genes induced by bleomycin. More importantly, AD-MSCs were found to inhibit pro-inflammatory related transcripts. CONCLUSIONS: Our results provided direct evidence that AD-MSC-mediated immunomodulation and anti-fibrotic effect in the lungs resulted in marked protection in pulmonary fibrosis, but at an early stage of disease.

2.
Indian J Dermatol ; 60(5): 520, 2015.
Article de Anglais | MEDLINE | ID: mdl-26538718

RÉSUMÉ

BACKGROUND: Growth factors have long been known as an effective treatment for facial wrinkles. We developed growth factor concentrate (GFC) from the platelets and evaluated their clinical outcome in nasolabial folds. AIMS AND OBJECTIVES: We evaluated safety and efficacy of autologous GFC on patients with nasolabial folds. MATERIALS AND METHODS: Study was conducted on 80 patients for nasolabial folds in two groups. Group I (20) received bilateral single injection of GFC and group II (60) received single injection of GFC on the right side of the face and platelet-rich plasma (PRP) on the left side of the face. Severity of nasolabial folds was determined at the baseline and 3 months of follow-up visits based on wrinkle severity rating scale (WSRS), Global aesthetic improvement scale (GAIS) and atlas photographic grading at rest and at full smile. Objective clinical assessment and subjective satisfaction scale was determined for overall improvement at the end of the study. RESULTS: In group I, 2 subjects showed improvement after GFC treatment with the score of 3.1-4 (76-100%), 3 subjects with the score of 2.1-3 (51-75%), 14 with the score of 1.1-2 (26-50%) and 1 subject with the score of 0-1 (<25%) at the end of study. In group II, 51 subjects were evaluated at the end of study where, 34 (66%) showed superior improvements after GFC, 6 (11%) patients showed similar improvement on both side of the face, 10 (19.6%) patients showed no noticeable improvement on the either side of the face and only 1 patient (1.96%) showed superior improvement for PRP at the end of the study. Overall improvement score analysis showed that GFC was significantly superior to PRP (P < 0.001). CONCLUSION: Present study is a strong evidence to support the use of GFC for nasolabial folds. The results showed that the single application of GFC is highly effective and safe.

3.
J Biomed Mater Res B Appl Biomater ; 102(8): 1825-34, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-24723571

RÉSUMÉ

Human bone marrow-derived mesenchymal stem cells (hMSCs) are an ideal osteogenic cell source for bone tissue engineering (BTE). A scaffold, in the context of BTE, is the extracellular matrix (ECM) that provides the unique microenvironment and play significant role in regulating cell behavior, differentiation, and development in an in vitro culture system. In this study, we have developed novel biomimetic tripolymer scaffolds for BTE using an ECM protein, collagen type 1; an ECM glycosaminoglycan, hyaluronic acid; and a natural osteoconductive polymer, chitosan. The scaffolds were characterized by scanning electron microscopy (SEM) and swelling ratio. The scaffolds were seeded with hMSCs and tested for cytocompatibility and osteogenic potential. The scaffolds supported cell adhesion, enhanced cell proliferation, promoted cell migration, showed good cell viability, and osteogenic potential. The cells were able to migrate out from the scaffolds in favorable conditions. SEM, alkaline phosphatase assay, and immunofluorescent staining confirmed the differentiation of hMSCs to osteogenic lineage in the scaffolds. In conclusion, we have successfully developed biomimetic scaffolds that supported the proliferation and differentiation of hMSCs. These scaffolds hold great promise as a cell-delivery vehicle for regenerative therapies and as a support system for enhancing bone regeneration.


Sujet(s)
Matériaux biomimétiques/composition chimique , Cellules de la moelle osseuse/métabolisme , Chitosane/composition chimique , Collagène de type I/composition chimique , Acide hyaluronique/composition chimique , Cellules souches mésenchymateuses/métabolisme , Structures d'échafaudage tissulaires/composition chimique , Adulte , Cellules de la moelle osseuse/cytologie , Régénération osseuse , Différenciation cellulaire , Mouvement cellulaire , Prolifération cellulaire , Survie cellulaire , Cellules cultivées , Femelle , Humains , Mâle , Cellules souches mésenchymateuses/cytologie , Ostéogenèse , Ingénierie tissulaire
4.
J Tissue Eng Regen Med ; 8(2): 143-52, 2014 Feb.
Article de Anglais | MEDLINE | ID: mdl-22499338

RÉSUMÉ

Extracellular matrix plays an important role in regulating cell growth and differentiation. The biomimetic approach of cell-based tissue engineering is based on mirroring this in vivo micro environment for developing a functional tissue engineered construct. In this study, we treated normal tissue culture plates with selected extracellular matrix components consisting of glycosaminoglycans such as chondroitin-4-sulphate, dermatan sulphate, chondroitin-6-sulphate, heparin and hyaluronic acid. Mesenchymal stem cells isolated from adult human bone marrow were cultured on the glycosaminoglycan treated culture plates to evaluate their regulatory role in cell growth and osteoblast differentiation. Although no significant improvement on human mesenchymal stem cell adhesion and proliferation was observed on the glycosaminoglycan-treated tissue culture plates, there was selective osteoblast differentiation, indicating its potential role in differentiation rather than proliferation. Osteoblast differentiation studies showed high osteogenic potential for all tested glycosaminoglycans except chondroitin-4-sulphate. Osteoblast differentiation-associated genes such as osterix, osteocalcin, integrin binding sialoprotein, osteonectin and collagen, type 1, alpha 1 showed significant upregulation. We identified osterix as the key transcription factor responsible for the enhanced bone matrix deposition observed on hyaluronic acid, heparin and chondroitin-6-sulphate. Hyaluronic acid provided the most favourable condition for osteoblast differentiation and bone matrix synthesis. Our results confirm and emphasise the significant role of extracellular matrix in regulating cell differentiation. To summarise, glycosaminoglycans of extracellular matrix played a significant role in regulating osteoblast differentiation and could be exploited in the biomimetic approach of fabricating or functionalizing scaffolds for stem cell based bone tissue engineering.


Sujet(s)
Cellules de la moelle osseuse/cytologie , Différenciation cellulaire/effets des médicaments et des substances chimiques , Glycosaminoglycanes/pharmacologie , Cellules souches mésenchymateuses/cytologie , Ostéoblastes/cytologie , Adulte , Phosphatase alcaline/métabolisme , Animaux , Cellules de la moelle osseuse/effets des médicaments et des substances chimiques , Cellules de la moelle osseuse/métabolisme , Trame osseuse/effets des médicaments et des substances chimiques , Trame osseuse/métabolisme , Calcification physiologique/effets des médicaments et des substances chimiques , Calcium/métabolisme , Bovins , Différenciation cellulaire/génétique , Survie cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/génétique , Cellules cultivées , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Cellules souches mésenchymateuses/effets des médicaments et des substances chimiques , Cellules souches mésenchymateuses/métabolisme , Ostéoblastes/effets des médicaments et des substances chimiques , Ostéoblastes/métabolisme , Sus scrofa
5.
Differentiation ; 84(2): 185-92, 2012 Sep.
Article de Anglais | MEDLINE | ID: mdl-22664173

RÉSUMÉ

The biomimetic approach of tissue engineering exploits the favorable properties of the extracellular matrix (ECM), to achieve better scaffold performance and tissue regeneration. ECM proteins regulate cell adhesion and differentiation through integrin mediated signal transduction. In the present study, we have examined the role of ECM proteins such as collagen type I, fibronectin, laminin and vitronectin in regulating the proliferation and osteogenic differentiation of bone marrow derived human mesenchymal stem cells (hMSCs). hMSCs were grown on selected ECM protein treated tissue culture plates. The growth kinetics was assessed by calculating the doubling time of the cells on different ECM treated plates. The cells were directed to osteoblast lineage by growing them in osteogenic induction media for 21 day. Differentiation was evaluated at different time points by osteoblast differentiation associated gene expression, alkaline phosphatase (ALP) activity, histochemical staining for mineralized matrix and calcium quantification. The doubling time of hMSCs cultured on collagen type I was significantly low, which was followed by laminin and fibronectin treated plates. However, doubling time of hMSCs cultured on vitronectin treated plate was not significantly different than that of the untreated control. High ALP gene (ALPL) expression and associated enhancement of mineralization were observed on collagen type I, fibronectin and vitronectin treated plates. Collagen type I showed early onset of mineralization with high ALP activity and up-regulation of osteopontin, ALPL, bone sialoprotein and osteocalcin genes. Vitronectin also up-regulated these genes and showed the highest amount of calcium in the secreted mineral matrix. Therefore, we conclude that, ECM proteins indeed modified the growth patterns and induced the osteoblast differentiation of hMSCs. Our findings have significant implication for bone tissue engineering applications.


Sujet(s)
Cellules de la moelle osseuse/cytologie , Différenciation cellulaire , Protéines de la matrice extracellulaire/métabolisme , Cellules souches mésenchymateuses/cytologie , Ostéoblastes/cytologie , Phosphatase alcaline/métabolisme , Calcium/métabolisme , Prolifération cellulaire , Cellules cultivées , Régulation de l'expression des gènes , Humains , Cellules souches mésenchymateuses/métabolisme , Transcription génétique
6.
Biochem Biophys Res Commun ; 414(1): 270-6, 2011 Oct 14.
Article de Anglais | MEDLINE | ID: mdl-21951845

RÉSUMÉ

The biomimetic approach mimicking in vivo micro environment is the key for developing functional tissue engineered constructs. In this study, we used a tripolymer combination consisting of a natural polymer, chitosan and two extracellular matrix components; collagen type 1 and hyaluronic acid to coat tissue culture plate to evaluate their effect on osteogenic differentiation of human bone marrow derived mesenchymal stem cells (hMSCs). The polymers were blended at different mixing ratios and the tissue culture plates were coated either by polyblend method or by surface modification method. hMSCs isolated from adult bone marrow were directed to osteoblast differentiation on the coated plates. Our results showed that the tripolymer coating of the tissue culture plate enhanced mineralization as evidenced by calcium quantification exhibiting significantly higher amount of calcium compared to the untreated or individual polymer coated plates. We found that the tripolymer coated plates having a 1:1 mixing ratio of chitosan and collagen type 1, surface modified with hyaluronic acid is an ideal combination to achieve the synergistic effect of these polymers on in vitro osteogenic differentiation of hMSCs. These results thus, establish a novel biomimetic approach of surface modification to enhance osteoblast differentiation and mineralization. Our findings hold great promise in implementing a biomimetic surface coating to improve osteoconductivity of implants and scaffolds for various orthopaedic and bone tissue engineering applications.


Sujet(s)
Matériaux biomimétiques/pharmacologie , Chitosane/pharmacologie , Matériaux revêtus, biocompatibles/pharmacologie , Collagène de type I/pharmacologie , Acide hyaluronique/pharmacologie , Cellules souches mésenchymateuses/effets des médicaments et des substances chimiques , Ostéogenèse/effets des médicaments et des substances chimiques , Ingénierie tissulaire/méthodes , Cellules de la moelle osseuse/cytologie , Cellules de la moelle osseuse/effets des médicaments et des substances chimiques , Différenciation cellulaire/effets des médicaments et des substances chimiques , Synergie des médicaments , Humains , Cellules souches mésenchymateuses/cytologie , Ostéoblastes/cytologie , Ostéoblastes/effets des médicaments et des substances chimiques
7.
Stem Cell Res ; 5(3): 244-54, 2010 Nov.
Article de Anglais | MEDLINE | ID: mdl-20880767

RÉSUMÉ

MSCs are promising candidates for stem cell therapy and regenerative medicine. Umbilical cord is the easiest obtainable biological source of MSCs and the Wharton's jelly of the umbilical cord is a rich source of fetus-derived stem cells. However, the use of MSCs for therapeutic application is based on their subsequent large-scale in vitro expansion. A fast and efficient protocol for generation of large quantities of MSCs is required to meet the clinical demand and biomedical research needs. Here we have optimized conditions for scaling up of WJ-MSCs. Low seeding density along with basic fibroblast growth factor (bFGF) supplementation in the growth medium, which is DMEM-KO, resulted in propagation of more than 1 x 10(8) cells within a time period of 15 days from a single umbilical cord. The upscaled WJ-MSCs retained their differentiation potential and immunosuppressive capacity. They expressed the typical hMSC surface antigens and the addition of bFGF in the culture medium did not affect the expression levels of HLA-DR and CD 44. A normal karyotype was confirmed in the large-scale expanded WJ-MSCs. Hence, in this study we attempted rapid clinical-scale expansion of WJ-MSCs which would allow these fetus-derived stem cells to be used for various allogeneic cell-based transplantations and tissue engineering.


Sujet(s)
Techniques de culture cellulaire/méthodes , Cellules souches mésenchymateuses/cytologie , Cordon ombilical/cytologie , Différenciation cellulaire , Facteur de croissance fibroblastique de type 2/pharmacologie , Antigènes HLA-DR/métabolisme , Humains , Antigènes CD44/métabolisme , Immunophénotypage , Cellules souches mésenchymateuses/immunologie , Cordon ombilical/immunologie
8.
Int J Biol Sci ; 6(5): 499-512, 2010 Sep 09.
Article de Anglais | MEDLINE | ID: mdl-20877435

RÉSUMÉ

Multipotent mesenchymal stromal cells (MSCs) from Wharton's jelly (WJ) of umbilical cord bear higher proliferation rate and self-renewal capacity than adult tissue-derived MSCs and are a primitive stromal cell population. Stem cell niche or physiological microenvironment plays a crucial role in maintenance of stem cell properties and oxygen concentration is an important component of the stem cell niche. Low oxygen tension or hypoxia is prevalent in the microenvironment of embryonic stem cells and many adult stem cells at early stages of development. Again, in vivo, MSCs are known to home specifically to hypoxic events following tissue injuries. Here we examined the effect of hypoxia on proliferation and in vitro differentiation potential of WJ-MSCs. Under hypoxia, WJ-MSCs exhibited improved proliferative potential while maintaining multi-lineage differentiation potential and surface marker expression. Hypoxic WJ-MSCs expressed higher mRNA levels of hypoxia inducible factors, notch receptors and notch downstream gene HES1. Gene expression profile of WJ-MSCs exposed to hypoxia and normoxia was compared and we identified a differential gene expression pattern where several stem cells markers and early mesodermal/endothelial genes such as DESMIN, CD34, ACTC were upregulated under hypoxia, suggesting that in vitro culturing of WJ-MSCs under hypoxic conditions leads to adoption of a mesodermal/endothelial fate. Thus, we demonstrate for the first time the effect of hypoxia on gene expression and growth kinetics of WJ-MSCs. Finally, although WJ-MSCs do not induce teratomas, under stressful and long-term culture conditions, MSCs can occasionally undergo transformation. Though there were no chromosomal abnormalities, certain transformation markers were upregulated in a few of the samples of WJ-MSCs under hypoxia.


Sujet(s)
Prolifération cellulaire , Cellules souches mésenchymateuses/cytologie , Oxygène/métabolisme , Cordon ombilical/cytologie , Marqueurs biologiques , Différenciation cellulaire , Hypoxie cellulaire , Transformation cellulaire néoplasique , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes , Humains , Sous-unité alpha du facteur-1 induit par l'hypoxie/génétique , Sous-unité alpha du facteur-1 induit par l'hypoxie/métabolisme , Caryotypage , Cellules souches mésenchymateuses/métabolisme , ARN messager/métabolisme , Récepteurs Notch/génétique , Récepteurs Notch/métabolisme , Transduction du signal
9.
In Vitro Cell Dev Biol Anim ; 46(9): 764-73, 2010 Oct.
Article de Anglais | MEDLINE | ID: mdl-20725801

RÉSUMÉ

Stem cells isolated from dental pulp possess the capacity for self-renewal and the potential for multi-lineage differentiation. However, dental pulp stem cells have different characteristics in terms of their culture conditions. The success of stem cells culture is governed by its micro-environmental niche. Therefore, we studied the effects of culture niche on long-term expansion of dental pulp stem cells in terms of cell morphology, growth kinetics, senescence pattern, cell surface marker expression differentiation capacity, and seeding plating density of dental pulp stem cells in four different, widely used media composition Among the various basal media tested, α-minimum essential media and knock out-minimum essential media supplemented with 10% fetal bovine serum were found to be the most optimal media composition in preserving the phenotypic characteristics and differentiation potential for prolonged periods as compared with DMEM-F12 and DMEM-LG. Plating density has been shown to affect overall yield. As a conclusion, the adoption of an appropriate culture system significantly improved cell yield, thus enabling the attainment of sufficient yields for therapeutic applications economizing in terms of cost of production and minimizing seeding cell density for maximum yield.


Sujet(s)
Techniques de culture cellulaire/méthodes , Milieux de culture/composition chimique , Pulpe dentaire/cytologie , Cellules souches multipotentes/cytologie , Adolescent , Analyse de variance , Numération cellulaire , Prolifération cellulaire/effets des médicaments et des substances chimiques , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Amorces ADN/génétique , Cytométrie en flux , Humains , Caryotypage , Cinétique , RT-PCR , Jeune adulte
10.
J Endod ; 36(9): 1504-15, 2010 Sep.
Article de Anglais | MEDLINE | ID: mdl-20728718

RÉSUMÉ

INTRODUCTION: Lately, several new stem cell sources and their effective isolation have been reported that claim to have potential for therapeutic applications. However, it is not yet clear which type of stem cell sources are most potent and best for targeted therapy. Lack of understanding of nature of these cells and their lineage-specific propensity might hinder their full potential. Therefore, understanding the gene expression profile that indicates their lineage-specific proclivity is fundamental to the development of successful cell-based therapies. METHODS: We compared proliferation rate, gene expression profile, and lineage-specific propensity of stem cells derived from human deciduous (SCD) and permanent teeth (DPSCs) over 5 passages. RESULTS: The proliferation rate of SCD was higher (cell number, 25 x 10(6) cells/mL; percent colony-forming units [CFUs], 151.67 +/- 10.5; percent cells in S/G2 phase, 12.4 +/- 1.48) than that of DPSCs (cell number, 21 x 10(6) cells/mL; percent CFUs, 133 +/- 17.62; percent cells in S/G2 phase, 10.4 +/- 1.18). It was observed that fold expression of several pluripotent markers such as OCT4, SOX2, NANOG, and REX1 were higher (>2) in SCD as compared with DPSCs. However, DPSCs showed higher expression of neuroectodermal markers PAX6, GBX2, and nestin (fold expression >100). Similarly, higher neurosphere formation and neuronal marker expression (NF, GFAP) were found in the differentiated DPSCs into neuron-like cells as compared with SCD. CONCLUSIONS: This study thus demonstrates that both SCD and DPSCs exhibit specific gene expression profile, with clear-cut inclination of DPSCs toward neuronal lineage.


Sujet(s)
Différenciation cellulaire/physiologie , Lignage cellulaire/physiologie , Pulpe dentaire/cytologie , Cellules souches/classification , Adulte , Cellules souches adultes/classification , Cellules souches adultes/cytologie , Cellules souches adultes/physiologie , Analyse de variance , Antigènes de surface/classification , Antigènes de surface/physiologie , Prolifération cellulaire , Enfant , Enfant d'âge préscolaire , Denture permanente , Analyse de profil d'expression de gènes , Humains , Plaque neurale/cytologie , Plaque neurale/physiologie , Cellules souches pluripotentes/cytologie , Cellules souches pluripotentes/physiologie , Analyse en composantes principales , ARN/analyse , Cellules souches/cytologie , Cellules souches/physiologie , Dent de lait , Jeune adulte
11.
Cytotherapy ; 12(6): 792-806, 2010 Oct.
Article de Anglais | MEDLINE | ID: mdl-20524772

RÉSUMÉ

BACKGROUND AIMS: Spinal cord injury (SCI) is a medically untreatable condition for which stem cells have created hope. Pre-clinical and clinical studies have established that these cells are safe for transplantation. The dose dependency, survivability, route of administration, cell migration to injury site and effect on sensory and motor behavior in an SCI-induced paraplegic model were studied. METHODS: A spinal cord contusion injury model was established in rats. Bone marrow (BM) mesenchymal stromal cells (MSC) were tagged to facilitate tracing in vivo. Two different doses (2 and 5 million cells/kg body weight) and two different routes of infusion (site of injury and lumbar puncture) were tested during and after the spinal shock period. The animals were tested post-transplantation for locomotor capacity, motor control, sensory reflex, posture and body position. Stem cell migration was observed 1 month post-transplantation in spinal cord sections. RESULTS: The overall results demonstrated that transplantation of BM MSC significantly improved the locomotor and sensory behavior score in the experimental group compared with the sham control group, and these results were dose dependent. All the infused stem cells could be visualized at the site of injury and none was visualized at the injected site. This indicated that the cells had survived in vivo, were probably chemoattracted and had migrated to the lesion site. CONCLUSIONS: MSC transplanted with a lumbar puncture method migrate to the site of injury and are the most suitable for SCI healing. These cells demonstrate a dose-dependent effect and promote functional recovery when injected during or after the spinal shock period.


Sujet(s)
Transplantation de cellules souches mésenchymateuses , Cellules souches mésenchymateuses/métabolisme , Traumatismes de la moelle épinière/thérapie , Cellules stromales/métabolisme , Animaux , Moelle osseuse/anatomopathologie , Mouvement cellulaire , Cellules cultivées , Protocoles cliniques , Modèles animaux de maladie humaine , Humains , Cellules souches mésenchymateuses/anatomopathologie , Activité motrice , Rats , Récupération fonctionnelle , Réflexe , Moelle spinale/anatomopathologie , Traumatismes de la moelle épinière/anatomopathologie , Traumatismes de la moelle épinière/physiopathologie , Cellules stromales/anatomopathologie , Cellules stromales/transplantation
12.
J Biomol Screen ; 15(6): 630-43, 2010 Jul.
Article de Anglais | MEDLINE | ID: mdl-20530724

RÉSUMÉ

Techniques to evaluate gene expression profiling, including real-time quantitative PCR, TaqMan low-density arrays, and sufficiently sensitive cDNA microarrays, are efficient methods for monitoring human embryonic stem cell (hESC) cultures. However, most of these high-throughput tests have a limited use due to high cost, extended turnaround time, and the involvement of highly specialized technical expertise. Hence, there is a paucity of rapid, cost-effective, robust, yet sensitive methods for routine screening of hESCs. A critical requirement in hESC cultures is to maintain a uniform undifferentiated state and to determine their differentiation capacity by showing the expression of gene markers representing all germ layers, including ecto-, meso-, and endoderm. To quantify the modulation of gene expression in hESCs during their propagation, expansion, and differentiation via embryoid body (EB) formation, the authors developed a simple, rapid, inexpensive, and definitive multimarker, semiquantitative multiplex RT-PCR (mxPCR) platform technology. Among the 15 gene primers tested, 4 were pluripotent markers comprising set 1, and 3 lineage-specific markers from each ecto-, meso-, and endoderm layers were combined as sets 2 to 4, respectively. The authors found that these 4 sets were not only effective in determining the relative differentiation in hESCs, but were easily reproducible. In this study, they used the HUES-7 cell line to standardize the technique, which was subsequently validated with HUES-9, NTERA-2, and mouse embryonic fibroblast cells. This single-reaction mxPCR assay was flexible and, by selecting appropriate reporter genes, can be designed for characterization of different hESC lines during routine maintenance and directed differentiation.


Sujet(s)
Différenciation cellulaire , Cellules souches embryonnaires/cytologie , Cellules souches embryonnaires/métabolisme , Réaction de polymérisation en chaîne/méthodes , Animaux , Marqueurs biologiques/métabolisme , Différenciation cellulaire/génétique , Lignée cellulaire , Embryon de mammifère/cytologie , Embryon de mammifère/métabolisme , Technique d'immunofluorescence , Régulation de l'expression des gènes au cours du développement , Humains , Souris , Normes de référence , Reproductibilité des résultats
13.
Transl Res ; 155(2): 62-70, 2010 Feb.
Article de Anglais | MEDLINE | ID: mdl-20129486

RÉSUMÉ

Parkinson's disease (PD) is a progressive neurodegenerative disease for which stem cell research has created hope in the last few years. Seven PD patients aged 22 to 62 years with a mean duration of disease 14.7+/-7.56 years were enrolled to participate in the prospective, uncontrolled, pilot study of single-dose, unilateral transplantation of autologous bone-marrow-derived mesenchymal stem cells (BM-MSCs). The BM-MSCs were transplanted into the sublateral ventricular zone by stereotaxic surgery. Patients were followed up for a period that ranged from 10 to 36 months. The mean baseline "off" score was 65+/-22.06, and the mean baseline "on" score was 50.6+/-15.85. Three of 7 patients have shown a steady improvement in their "off"/"on" Unified Parkinson's Disease Rating Scale (UPDRS). The mean "off" score at their last follow-up was 43.3 with an improvement of 22.9% from the baseline. The mean "on" score at their last follow-up was 31.7, with an improvement of 38%. Hoehn and Yahr (H&Y) and Schwab and England (S&E) scores showed similar improvements from 2.7 and 2.5 in H&Y and 14% improvement in S&E scores, respectively. A subjective improvement was found in symptoms like facial expression, gait, and freezing episodes; 2 patients have significantly reduced the dosages of PD medicine. These results indicate that our protocol seems to be safe, and no serious adverse events occurred after stem-cell transplantation in PD patients. The number of patients recruited and the uncontrolled nature of the trial did not permit demonstration of effectiveness of the treatment involved. However, the results encourage future trials with more patients to demonstrate efficacy.


Sujet(s)
Cellules de la moelle osseuse/cytologie , Transplantation de cellules souches mésenchymateuses , Maladie de Parkinson/chirurgie , Récupération fonctionnelle , Adulte , Cellules cultivées , Études de faisabilité , Études de suivi , Humains , Immunophénotypage , Imagerie par résonance magnétique , Mâle , Transplantation de cellules souches mésenchymateuses/effets indésirables , Adulte d'âge moyen , Maladie de Parkinson/anatomopathologie , Projets pilotes , Techniques stéréotaxiques , Transplantation autologue , Résultat thérapeutique , Jeune adulte
14.
J Stem Cells ; 5(2): 89-101, 2010.
Article de Anglais | MEDLINE | ID: mdl-22049619

RÉSUMÉ

Tumor tissue repositories (TTRs) play a pivotal role in both basic and translational research by acting as a conduit to facilitate innovative research, thereby providing solutions to treat the incurable disease--'Cancer'. One of the fundamental requirements to achieve this goal would be the acquisition of high quality tumor tissue specimens that are stored in such a manner that its integrity is preserved. Further, a quality system should be in place that assures the compliance of procedures that are the key to a smooth functioning of all the inter-related departments that play a key role in the entire operations. To address this, we have initiated an effort to build a tumor tissue repository of brain tumor tissues in the Southern part of the Indian sub-continent. One of the cardinal features of brain tumors is the heterogeneity, both phenotypically and genotypically. Moreover, significant gaps exist in current understanding of the molecular pathways involved in the genesis, progression, and biological and clinical behavior of brain tumors. We hope that our initiative will provide researchers accessibility to a reserve of high quality tissues in this part of the globe. We have created and validated a complete histology service including tissue processing, embedding, sectioning and H&E staining for fixed tissues, in addition to creating and staining frozen sections. To our knowledge, such a structured initiative to store brain tumor samples is the first of its kind in the India.


Sujet(s)
Recherche biomédicale/organisation et administration , Tumeurs du cerveau/anatomopathologie , Contrôle de qualité , Banques de tissus/organisation et administration , Banques de tissus/normes , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Recherche biomédicale/éthique , Tumeurs du cerveau/génétique , Tumeurs du cerveau/métabolisme , Enfant , Cryoconservation , Femelle , Humains , Techniques immunoenzymatiques , Mâle , Adulte d'âge moyen , ARN messager/génétique , ARN tumoral/génétique , RT-PCR , Manipulation d'échantillons , Donneurs de tissus , Jeune adulte
15.
Curr Stem Cell Res Ther ; 5(1): 2-12, 2010 Mar.
Article de Anglais | MEDLINE | ID: mdl-19951253

RÉSUMÉ

Human embryonic stem cells (hESC) differentiate spontaneously in culture and develop a complex microenvironment comprising of autologously derived niche that in turn supports their pluripotency. The basic hypothesis that we deal with is that hESCs undergoing differentiation, sequentially generate trophectoderm and endoderm lineages and thereafter influence further events through the production of growth factors. These factors control the fate of hESCs either by promoting or retarding the recruitment of new cells in the differentiation program. This scenario therefore represents an analog of the in vivo situation in which extra-embryonic tissues influence the behavior of the inner cell mass (ICM). The premise of the paper is the Rho kinase inhibitor Y27632 that can spatiotemporally alter this balance between pluripotency and differentiation. To evaluate the composition and inclination of lineage specification during spontaneous differentiation, we have studied the hESC colonies and their surrounding niche as interdependent entities. We show that the population of fibroblastic niche that surrounds hESC colonies co-expresses trophectoderm and niche cell markers including SSEA1, hCG, progesterone, HAND1, pSmad1 and FGFR1 as early as day 4. A sudden increase in the expression of GATA4 and AFP secretion indicated putative endoderm formation on day 6 in both control and Y27632 treated cultures. On day 6, 20 microM of Y27632 supplementation significantly reduced the trophectoderm-like niche population without affecting endoderm formation, enhanced the average size and number of hESC colonies, decreased IGF1 secretion thereby improving the pluripotency. Overall our findings support the afore mentioned hypothesis and demonstrate that closely packed epithelial trophectoderm-like cells bordering the hESC colonies present an initial and imminent localized niche which is spatiotemporally regulated. Such advances in understanding the behavior and modulation of hESC and its surrounding niche would facilitate better differentiation protocols for applications in regenerative medicine and drug screening.


Sujet(s)
Amides/pharmacologie , Différenciation cellulaire/effets des médicaments et des substances chimiques , Cellules souches embryonnaires/effets des médicaments et des substances chimiques , Protéine-1 de liaison aux IGF/biosynthèse , Pyridines/pharmacologie , rho-Associated Kinases/antagonistes et inhibiteurs , Antigènes de différenciation/métabolisme , Lignée cellulaire , Ectoderme/cytologie , Cellules souches embryonnaires/cytologie , Cellules souches embryonnaires/métabolisme , Endoderme/cytologie , Facteur de transcription GATA-4/génétique , Facteur de transcription GATA-4/métabolisme , Humains , Protéine-1 de liaison aux IGF/génétique , Protéine-1 de liaison aux IGF/métabolisme , Niche de cellules souches/cytologie , Niche de cellules souches/effets des médicaments et des substances chimiques , Cellules souches , Alphafoetoprotéines/génétique , Alphafoetoprotéines/métabolisme
16.
Stem Cells Dev ; 19(1): 117-30, 2010 Jan.
Article de Anglais | MEDLINE | ID: mdl-19619003

RÉSUMÉ

Mesenchymal stem cells (MSCs) with their multilineage developmental plasticity comprise a promising tool for regenerative cell-based therapy. Despite important biological properties, which the MSCs from different sources share, the differences between them are poorly understood. Hence, it is required to assign a molecular signature to each of these MSC populations, based on stem cell related genes and early lineage or developmental markers. Understanding their propensity to differentiate to different lineages is fundamental for the development of successful cell-based therapies. Culture expansion of MSCs is a prerequisite, since high absolute numbers of stem cells are required to attain a clinical dose. Here, we compared the different culture conditions for long-term expansion of human MSCs isolated from the Wharton's jelly (WJ) of the umbilical cord while preserving their stem cell characteristics and differentiation potential. We find that DMEM-KO and DMEM-F12 are superior as compared to the other media tested in supporting the in vitro expansion of the WJ-MSCs. We studied the gene expression profile of WJ and bone marrow-derived MSCs (BM-MSCs) both at early and late passages using Human Stem Cell Pluripotency Array, and our data revealed differences at the transcriptional level between the two MSC types. Compared to BM-MSCs, WJ-MSCs had higher expression of undifferentiated human embryonic stem cell (hES) markers like NANOG, DNMT3B, and GABRB3, pluripotent/stem cell markers, as well as some early endodermal markers both at early and late passages. To conclude, WJ-MSCs possess properties of true stem cells, which they retain even after extended in vitro culturing.


Sujet(s)
Marqueurs biologiques/analyse , Prolifération cellulaire , Cellules souches mésenchymateuses/métabolisme , Cellules souches mésenchymateuses/physiologie , Cordon ombilical/cytologie , Adulte , Marqueurs biologiques/métabolisme , Cellules de la moelle osseuse/cytologie , Cellules de la moelle osseuse/métabolisme , Cellules de la moelle osseuse/physiologie , Différenciation cellulaire/physiologie , Séparation cellulaire , Cellules cultivées , Femelle , Analyse de profil d'expression de gènes , Humains , Nouveau-né , Mâle , Séquençage par oligonucléotides en batterie , Cellules souches pluripotentes/métabolisme , Cellules souches pluripotentes/physiologie , Facteurs temps , Cordon ombilical/métabolisme , Cordon ombilical/physiologie , Jeune adulte
17.
Cytotherapy ; 11(7): 897-911, 2009.
Article de Anglais | MEDLINE | ID: mdl-19903102

RÉSUMÉ

BACKGROUND AIMS: Spinal cord injury (SCI) is a medically untreatable condition for which stem cells have created hope in the last few years. Earlier pre-clinical reports have shown that transplantation of bone marrow (BM) mesenchymal stromal cells (MSC) in SCI-simulated models can produce encouraging results. In a clinical pilot study, we investigated the growth kinetics of BM MSC from SCI patients, their safety and functional improvement post-transplantation. METHODS: Thirty patients with clinically complete SCI at cervical or thoracic levels were recruited and divided into two groups based on the duration of injury. Patients with <6 months of post-SCI were recruited into group 1 and patients with >6 months of post-SCI were included into group 2. Autologous BM was harvested from the iliac crest of SCI patients under local anesthesia and BM MSC were isolated and expanded ex vivo. BM MSC were tested for quality control, characterized for cell surface markers and transplanted back to the patient via lumbar puncture at a dose of 1 x 10(6) cells/kg body weight. RESULTS: At the time of writing, three patients had completed 3 years of follow-up post-BM MSC administration, 10 patients 2 years follow-up and 10 patients 1 year follow-up. Five patients have been lost to follow-up. None of the patients have reported any adverse events associated with BM MSC transplantation. CONCLUSIONS: The results indicate that our protocol is safe with no serious adverse events following transplantation in SCI patients. The number of patients recruited and the uncontrolled nature of the trial do not permit demonstration of the effectiveness of the treatment involved. However, the results encourage further trials with higher doses and different routes of administration in order to demonstrate the recovery/efficacy if any, in SCI patients.


Sujet(s)
Cellules de la moelle osseuse/métabolisme , Transplantation de cellules souches mésenchymateuses , Traumatismes de la moelle épinière/thérapie , Cellules stromales/métabolisme , Adolescent , Adulte , Cellules de la moelle osseuse/anatomopathologie , Prolifération cellulaire , Cellules cultivées , Potentiels évoqués somatosensoriels , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Conduction nerveuse , Paraplégie , Projets pilotes , Traumatismes de la moelle épinière/anatomopathologie , Traumatismes de la moelle épinière/physiopathologie , Cellules stromales/anatomopathologie , Transplantation autologue
18.
J Biomed Sci ; 16: 88, 2009 Sep 22.
Article de Anglais | MEDLINE | ID: mdl-19772618

RÉSUMÉ

Trophoblast differentiation and formation of the placenta are important events linked to post-implantation embryonic development. Models mimicking the biology of trophoblast differentiation in a post-implantation maternal microenvironment are needed for understanding disorders like placental-ischemia or for applications in drug-screening, and would help in overcoming the ethical impasse on using human embryos for such research. Here we attempt to create such a model by using embryoid bodies (EBs) and a biomimetic platform composed of a bilayer of fibronectin and gelatin on top of low-melting agarose. Using this model we test the hypothesis that cystic-EBs (day 30) that resemble blastocysts morphologically, are better sources as compared to noncytic EBs (day 10), for functional trophoblast differentiation; and that the Rho kinases inhibitor Y27632 can enhance this differentiation. Non/cytic EBs with/out Y27632 were grown on this platform for 28 days, and screened from secretion and expression of trophoblast and other lineage markers using ECLIA, RT-PCR, and Immunofluorescence. All EBs attached on this surface and rapidly proliferated into hCG and progesterone (P2) secreting functional trophoblast cells. However, the cells derived from cytic-EBs and cytic-EBs+ Y27632 showed the maximum secretion of these hormones and expressed IGF2, supporting our hypothesis. Also Y27632 reduced extraembryonic endoderm and trophoblast lineage differentiation from early noncystic-EBs, whereas, it specifically enhanced the induction of trophoblast and multinucleated syncitiotrophoblast differentiation from late cystic-EBs. In vivo trophoblast differentiation can be replicated in fibronectin based biomaterials, using cytic-EBs and by maneuvering the Rho-ROCK pathways. Response of EBs to a compound may vary temporally, and determination of their right stage is crucial for applications in directed-differentiation or drug-screening.


Sujet(s)
Amides/pharmacologie , Blastocyste/effets des médicaments et des substances chimiques , Milieux de culture/pharmacologie , Organoïdes/effets des médicaments et des substances chimiques , Inhibiteurs de protéines kinases/pharmacologie , Pyridines/pharmacologie , Trophoblastes/cytologie , Blastocyste/cytologie , Différenciation cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire/effets des médicaments et des substances chimiques , Lignage cellulaire , Polarité de la cellule/effets des médicaments et des substances chimiques , Gonadotrophine chorionique/métabolisme , Développement embryonnaire/effets des médicaments et des substances chimiques , Cellules souches embryonnaires/cytologie , Cellules souches embryonnaires/effets des médicaments et des substances chimiques , Endoderme/effets des médicaments et des substances chimiques , Fibronectines , Gélatine , Humains , Modèles biologiques , Organoïdes/cytologie , Progestérone/métabolisme , Agarose , Alphafoetoprotéines/métabolisme , rho-Associated Kinases/antagonistes et inhibiteurs
19.
Exp Biol Med (Maywood) ; 234(10): 1230-43, 2009 Oct.
Article de Anglais | MEDLINE | ID: mdl-19546356

RÉSUMÉ

Human embryonic stem cells (hESCs) are able to stably maintain their characteristics for an unlimited period; nevertheless, substantial differences among cell lines in gene and protein expression not manifested during the undifferentiated state may appear when cells differentiate. It is widely accepted that developing an efficient protocol to control the differentiation of hESCs will enable us to produce adequate numbers of desired cell types with relative ease for diverse applications ranging from basic research to cell therapy and drug screening. Hence of late, there has been considerable interest in understanding whether and how hESC lines are equivalent or different to each other in their in vitro developmental tendencies. In this study, we compared the developmental competences of two hESC lines (HUES-9 and HUES-7) at molecular, cellular and functional levels, upon spontaneous differentiation without any added inducing agents. Both cell lines generated the three embryonic germ layers, extra-embryonic tissues and primordial germ cells during embryoid body (EB) formation. However HUES-9 showed a stronger propensity towards formation of neuroectodermal lineages, whereas HUES-7 differentiated preferentially into mesoderm and endoderm. Upon further differentiation, HUES-9 generated largely neural cells (neurons, oligodendrocytes, astrocytes and gangliosides) whereas HUES-7 formed mesendodermal derivatives, including cardiomyocytes, skeletal myocytes, endothelial cells, hepatocytes and pancreatic cells. Overall, our findings endorse the hypothesis that independently-derived hESCs biologically differ among themselves, thereby displaying varying differentiation propensity. These subtle differences not only highlight the importance of screening and deriving lines for lineage-specific differentiation but also indicate that individual lines may possess a repertoire of capabilities that is unique.


Sujet(s)
Lignée cellulaire , Cellules souches embryonnaires/cytologie , Cellules souches embryonnaires/physiologie , Marqueurs biologiques/métabolisme , Différenciation cellulaire , Lignage cellulaire , Cellules cultivées , Ectoderme/cytologie , Cellules souches embryonnaires/métabolisme , Endoderme/cytologie , Technique d'immunofluorescence indirecte , Humains , Immunohistochimie , Caryotypage , Mésoderme/cytologie , Cellules souches pluripotentes/cytologie , Cellules souches pluripotentes/métabolisme
20.
J Tissue Eng Regen Med ; 3(3): 163-74, 2009 Mar.
Article de Anglais | MEDLINE | ID: mdl-19229888

RÉSUMÉ

Human adult bone marrow-derived mesenchymal stem cells (MSCs) are a promising tool in the newly emerging avenue of regenerative medicine. MSCs have already been translated from basic research to clinical transplantation research. However, there is still a lack of consensus on the ideal method of culturing MSCs. Here we have compared different culture conditions of human MSCs with an attempt to preserve their characteristics and multi-lineage differentiation potential. We compare the different basal culture media DMEM-F12, DMEM-high glucose (DMEM-HG), DMEM-low glucose (DMEM-LG), knock-out DMEM (DMEM-KO) and Mesencult on the proliferation rate, surface markers and differentiation potentials of MSCs. At every fifth passage until the 25th passage, the differentiation potential and the presence of a panel of surface markers was observed, using flow cytometry. We also compared the characteristics of human MSCs when cultured in reduced concentrations of fetal bovine serum (FBS), knockout serum replacement (KO-SR) and human plasma. Data indicate that the presence of serum is essential to sustain and propagate MSCs cultures. The choice of basal medium is equally important so as to preserve their characteristics and multipotent properties even after prolonged culture in vitro. With MSCs emerging as a popular tool for regenerative therapies in incurable diseases, it is essential to be able to obtain a large number of MSCs that continue to preserve their characteristics following passaging. The data reveal the optimum basal medium for prolonged culture of MSCs while retaining their ability to differentiate and hence this may be used for up-scaling to provide sufficient numbers for transplantation.


Sujet(s)
Cellules de la moelle osseuse/cytologie , Techniques de culture cellulaire/méthodes , Cellules souches mésenchymateuses/cytologie , Adipocytes/cytologie , Adulte , Marqueurs biologiques/métabolisme , Différenciation cellulaire , Membrane cellulaire/métabolisme , Forme de la cellule , Cellules cultivées , Milieux de culture , Cytométrie en flux , Humains , Caryotypage , Mâle , Ostéoblastes/cytologie , Phénotype , Facteurs temps
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