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1.
bioRxiv ; 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37131613

RESUMO

Cell therapy is promising to treat many conditions, including neurological and osteoarticular diseases. Encapsulation of cells within hydrogels facilitates cell delivery and can improve therapeutic effects. However, much work remains to be done to align treatment strategies with specific diseases. The development of imaging tools that enable monitoring cells and hydrogel independently is key to achieving this goal. Our objective herein is to longitudinally study an iodine-labeled hydrogel, incorporating gold-labeled stem cells, by bicolor CT imaging after in vivo injection in rodent brains or knees. To this aim, an injectable self-healing hyaluronic acid (HA) hydrogel with long-persistent radiopacity was formed by the covalent grafting of a clinical contrast agent on HA. The labeling conditions were tuned to achieve sufficient X-ray signal and to maintain the mechanical and self-healing properties as well as injectability of the original HA scaffold. The efficient delivery of both cells and hydrogel at the targeted sites was demonstrated by synchrotron K-edge subtraction-CT. The iodine labeling enabled to monitor the hydrogel biodistribution in vivo up to 3 days post-administration, which represents a technological first in the field of molecular CT imaging agents. This tool may foster the translation of combined cell-hydrogel therapies into the clinics.

2.
Nutrients ; 15(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37049592

RESUMO

Excess weight and obesity are the fifth leading cause of death globally, and sustained efforts from health professionals and researchers are required to mitigate this pandemic-scale problem. Polyphenols and flavonoids found in Aspalathus linearis-a plant widely consumed as Rooibos tea-are increasingly being investigated for their positive effects on various health issues including inflammation. The aim of our study was to examine the effect of Rooibos extract on obesity and the associated low-grade chronic inflammatory state by testing antioxidant activity, cytokine secretions, macrophage polarization and the differentiation of human adipocytes through the development of adipospheroids. Rooibos extract significantly decreased ROS production and the secretion of pro-inflammatory cytokines (IFN-γ, IL-12, IL-2 and IL-17a) in human leukocytes. Additionally, Rooibos extract down-regulated LPS-induced macrophage M1 polarization, shown by a significant decrease in the expression of pro-inflammatory cytokines: TNFα, IL-8, IL-6, IL-1ß and CXCL10. In addition, Rooibos inhibited intracellular lipid accumulation and reduced adipogenesis by decreasing the expression of PPARγ, Ap2 and HSL in adipospheroids. A significant decrease in leptin expression was noted and this, more interestingly, was accompanied by a significant increase in adiponectin expression. Using a co-culture system between macrophages and adipocytes, Rooibos extract significantly decreased the expression of all studied pro-inflammatory cytokines and particularly leptin, and increased adiponectin expression. Thus, adding Rooibos tea to the daily diet is likely to prevent the development of obesity associated with chronic low-level inflammation.


Assuntos
Aspalathus , Humanos , Leptina , Extratos Vegetais/farmacologia , Adiponectina , Obesidade/complicações , Inflamação , Adipócitos , Citocinas , Chá
3.
Plast Reconstr Surg ; 151(3): 420e-431e, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730531

RESUMO

SUMMARY: Over the past 30 years, there has been a dramatic increase in the use of autologous fat grafting for soft-tissue augmentation and to improve facial skin quality. Several studies have highlighted the impact of aging on adipose tissue, leading to a decrease of adipose tissue volume and preadipocyte proliferation and increase of fibrosis. Recently, there has been a rising interest in adipose tissue components, including adipose-derived stem/stromal cells (ASCs) because of their regenerative potential, including inflammation, fibrosis, and vascularization modulation. Because of their differentiation potential and paracrine function, ASCs have been largely used for fat grafting procedures, as they are described to be a key component in fat graft survival. However, many parameters as surgical procedures or adipose tissue biology could change clinical outcomes. Variation on fat grafting methods have led to numerous inconsistent clinical outcomes. Donor-to-donor variation could also be imputed to ASCs, tissue inflammatory state, or tissue origin. In this review, the authors aim to analyze (1) the parameters involved in graft survival, and (2) the effect of aging on adipose tissue components, especially ASCs, that could lead to a decrease of skin regeneration and fat graft retention. CLINICAL RELEVANCE STATEMENT: This review aims to enlighten surgeons about known parameters that could play a role in fat graft survival. ASCs and their potential mechanism of action in regenerative medicine are more specifically described.


Assuntos
Adipócitos , Tecido Adiposo , Humanos , Tecido Adiposo/transplante , Adipócitos/transplante , Envelhecimento , Células-Tronco , Fibrose , Sobrevivência de Enxerto
4.
Sci Rep ; 12(1): 4700, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35304540

RESUMO

With the aim of designing a preclinical study evaluating an intracerebral cell-based therapy for stroke, an observational study was performed in the rat suture model of ischemic stroke. Objectives were threefold: (i) to characterize neurofunctional and imaging readouts in the first weeks following transient ischemic stroke, according to lesion subtype (hypothalamic, striatal, corticostriatal); (ii) to confirm that intracerebral administration does not negatively impact these readouts; and (iii) to calculate sample sizes for a future therapeutic trial using these readouts as endpoints. Our results suggested that the most relevant endpoints were side bias (staircase test) and axial diffusivity (AD) (diffusion tensor imaging). Hypothalamic-only lesions did not affect those parameters, which were close to normal. Side bias in striatal lesions reached near-normal levels within 2 weeks, while rats with corticostriatal lesions remained impaired until week 14. AD values were decreased at 4 days and increased at 5 weeks post-surgery, with a subtype gradient: hypothalamic < striatal < corticostriatal. Intracerebral administration did not impact these readouts. After sample size calculation (18-147 rats per group according to the endpoint considered), we conclude that a therapeutic trial based on both readouts would be feasible only in the framework of a multicenter trial.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Animais , Terapia Baseada em Transplante de Células e Tecidos , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Ratos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia
5.
Plast Reconstr Surg Glob Open ; 10(1): e4056, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35186622

RESUMO

Intraoperative three-dimensional fabrication of living tissues could be the next biomedical revolution in patient treatment. APPROACH: We developed a surgery-ready robotic three-dimensional bioprinter and demonstrated that a bioprinting procedure using medical grade hydrogel could be performed using a 6-axis robotic arm in vivo for treating burn injuries. RESULTS: We conducted a pilot swine animal study on a deep third-degree severe burn model. We observed that the use of cell-laden bioink as treatment substantially affects skin regeneration, producing in situ fibroblast growth factor and vascular endothelial growth factor, necessary for tissue regeneration and re-epidermalization of the wound. CONCLUSIONS: We described an animal study of intraoperative three-dimensional bioprinting living tissue. This emerging technology brings the first proof of in vivo skin printing feasibility using a surgery-ready robotic arm-based bioprinter. Our positive outcome in skin regeneration, joined with this procedure's feasibility, allow us to envision the possibility of using this innovative approach in a human clinical trial in the near future.

6.
Stem Cell Res Ther ; 12(1): 480, 2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454629

RESUMO

BACKGROUND: In human subcutaneous adipose tissue, the superficial fascia distinguishes superficial and deep microenvironments showing extensions called retinacula cutis. The superficial subcutaneous adipose tissue has been described as hyperplastic and the deep subcutaneous adipose tissue as inflammatory. However, few studies have described stromal-vascular fraction (SVF) content and adipose-derived stromal/stem cells (ASCs) behavior derived from superficial and deep subcutaneous adipose tissue. In this study, we analyzed a third conjunctive microenvironment: the retinacula cutis superficialis derived from superficial subcutaneous adipose tissue. METHODS: The samples of abdominal human subcutaneous adipose tissue were obtained during plastic aesthetic surgery in France (Declaration DC-2008-162) and Brazil (Protocol 145/09). RESULTS: The SVF content was characterized in situ by immunofluorescence and ex vivo by flow cytometry revealing a high content of pre-adipocytes rather in superficial subcutaneous adipose tissue microenvironment. Adipogenic assays revealed higher percentage of lipid accumulation area in ASCs from superficial subcutaneous adipose tissue compared with retinacula cutis superficialis (p < 0.0001) and deep subcutaneous adipose tissue (p < 0.0001). The high adipogenic potential of superficial subcutaneous adipose tissue was corroborated by an up-regulation of adipocyte fatty acid-binding protein (FABP4) compared with retinacula cutis superficialis (p < 0.0001) and deep subcutaneous adipose tissue (p < 0.0001) and of C/EBPα (CCAAT/enhancer-binding protein alpha) compared with retinacula cutis superficialis (p < 0.0001) and deep subcutaneous adipose tissue (p < 0.0001) microenvironments. Curiously, ASCs from retinacula cutis superficialis showed a higher level of adiponectin receptor gene compared with superficial subcutaneous adipose tissue (p = 0.0409), widely known as an anti-inflammatory hormone. Non-induced ASCs from retinacula cutis superficialis showed higher secretion of human vascular endothelial growth factor (VEGF), compared with superficial (p = 0.0485) and deep (p = 0.0112) subcutaneous adipose tissue and with adipogenic-induced ASCs from superficial (p = 0.0175) and deep (p = 0.0328) subcutaneous adipose tissue. Furthermore, ASCs from retinacula cutis superficialis showed higher secretion of Chemokine (C-C motif) ligand 5 (CCL5) compared with non-induced (p = 0.0029) and induced (p = 0.0089) superficial subcutaneous adipose tissue. CONCLUSIONS: This study highlights the contribution to ASCs from retinacula cutis superficialis in their angiogenic property previously described for the whole superficial subcutaneous adipose tissue besides supporting its adipogenic potential for superficial subcutaneous adipose tissue.


Assuntos
Tela Subcutânea , Fator A de Crescimento do Endotélio Vascular , Adipogenia , Humanos , Gordura Subcutânea , Gordura Subcutânea Abdominal
7.
J Tissue Eng Regen Med ; 15(1): 37-48, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33170542

RESUMO

Clinical grade cultured epithelial autograft (CEA) are routinely used to treat burns covering more than 60% of the total body surface area. However, although the epidermis may be efficiently repaired by CEA, the dermal layer, which is not spared in deep burns, requires additional treatment strategies. Our aim is to develop an innovative method of skin regeneration based on in situ 3D bioprinting of freshly isolated autologous skin cells. We describe herein bioink formulation and cell preparation steps together with experimental data validating a straightforward enzyme-free protocol of skin cell extraction. This procedure complies with both the specific needs of 3D bioprinting process and the stringent rules of good manufacturing practices. This mechanical extraction protocol, starting from human skin biopsies, allows harvesting a sufficient amount of both viable and growing keratinocytes and fibroblasts. We demonstrated that a dermis may be reconstituted in vitro starting from a medical grade bioink and mechanically extracted skin cells. In these experiments, proliferation of the extracted cells can be observed over the first 21 days period after 3D bioprinting and the analysis of type I collagen exhibited a de novo production of extracellular matrix proteins. Finally, in vivo experiments in a murine model of severe burn provided evidences that a topical application of our medical grade bioink was feasible and well-tolerated. Overall, these results represent a valuable groundwork for the design of future 3D bioprinting tissue engineering strategies aimed at treating, in a single intraoperative step, patients suffering from extended severe burns.


Assuntos
Bioimpressão , Queimaduras , Células Imobilizadas , Fibroblastos , Queratinócitos , Impressão Tridimensional , Alicerces Teciduais/química , Animais , Queimaduras/metabolismo , Queimaduras/patologia , Queimaduras/terapia , Células Imobilizadas/metabolismo , Células Imobilizadas/patologia , Células Imobilizadas/transplante , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibroblastos/transplante , Xenoenxertos , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/transplante , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
8.
Int J Mol Sci ; 21(17)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878250

RESUMO

Adipose-derived mesenchymal stem cells (ASCs) are well known for their secretory potential, which confers them useful properties in cell therapy. Nevertheless, this therapeutic potential is reduced after transplantation due to their short survival in the human body and their migration property. This study proposes a method to protect cells during and after injection by encapsulation in microparticles of calcium alginate. Besides, the consequences of encapsulation on ASC proliferation, pluripotential, and secretome were studied. Spherical particles with a mean diameter of 500 µm could be obtained in a reproducible manner with a viability of 70% after 16 days in vitro. Moreover, encapsulation did not alter the proliferative properties of ASCs upon return to culture nor their differentiation potential in adipocytes, chondrocytes, and osteocytes. Concerning their secretome, encapsulated ASCs consistently produced greater amounts of interleukin-6 (IL-6), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF) compared to monolayer cultures. Encapsulation therefore appears to enrich the secretome with transforming growth factor ß1 (TGF-ß1) and macrophage inflammatory protein-1ß (MIP-1ß) not detectable in monolayer cultures. Alginate microparticles seem sufficiently porous to allow diffusion of the cytokines of interest. With all these cytokines playing an important role in wound healing, it appears relevant to investigate the impact of using encapsulated ASCs on the wound healing process.


Assuntos
Alginatos/química , Proliferação de Células , Citocinas/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Pluripotentes/metabolismo , Adulto , Alginatos/metabolismo , Diferenciação Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Humanos , Pessoa de Meia-Idade , Células-Tronco Pluripotentes/citologia
9.
Int J Mol Sci ; 21(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971882

RESUMO

Severe burn injuries remain a major health problem due to high rates of mortality, residual morbidity, and/or aesthetic damages. To find new therapies aimed at promoting a harmonious healing of skin burns, it is important to develop models which take into account the unique properties of the human skin. Based on previously described models of burn injury performed on human skin explants, we hypothesized that maintaining explants under constant tension forces would allow to more closely reproduce the pathophysiological processes of skin remodeling. We thus. Here, we set up and characterized an improved model of deep second-degree burn injury on ex vivo cultured human skin explants at air-liquid interface and maintained under conditions of constant tension forces. A spontaneous re-epithelialization of the lesion was observed 8 to 9 days post burn and was found to rely on the proliferation of basal keratinocytes at the wound edges. Collagen VII at the dermo-epidermal junction reformed along with the progression of re-epithelializatio and a synthesis of procollagen III was observed in the dermis at the wound site. These findings indicate that our model is suitable for the assessment of clinically-relevant therapies aimed at modulating the kinetics of re-epithelialization and/or the activation of fibroblasts following skin burn injuries. In this regard, we evaluated the use of a thermoreversible poloxamer hydrogel as a vehicle for topically-testable therapeutic molecules. Our data showed that, although useful for drug formulation, the p407/p188 poloxamer hydrogel induces a delay of skin re-epithelialization in humans skin explants submitted to experimental burn injury.


Assuntos
Queimaduras/metabolismo , Fibroblastos/metabolismo , Queratinócitos/metabolismo , Modelos Biológicos , Reepitelização , Pele/metabolismo , Queimaduras/patologia , Fibroblastos/patologia , Humanos , Queratinócitos/patologia , Pele/patologia , Técnicas de Cultura de Tecidos
10.
Sci Signal ; 13(639)2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32636307

RESUMO

Bone morphogenetic protein 1 (BMP-1) is an important metalloproteinase that synchronizes growth factor activation with extracellular matrix assembly during morphogenesis and tissue repair. The mechanisms by which BMP-1 exerts these effects are highly context dependent. Because BMP-1 overexpression induces marked phenotypic changes in two human cell lines (HT1080 and 293-EBNA cells), we investigated how BMP-1 simultaneously affects cell-matrix interactions and growth factor activity in these cells. Increasing BMP-1 led to a loss of cell adhesion that depended on the matricellular glycoprotein thrombospondin-1 (TSP-1). BMP-1 cleaved TSP-1 between the VWFC/procollagen-like domain and the type 1 repeats that mediate several key TSP-1 functions. This cleavage induced the release of TSP-1 C-terminal domains from the extracellular matrix and abolished its previously described multisite cooperative interactions with heparan sulfate proteoglycans and CD36 on HT1080 cells. In addition, BMP-1-dependent proteolysis potentiated the TSP-1-mediated activation of latent transforming growth factor-ß (TGF-ß), leading to increased signaling through the canonical SMAD pathway. In primary human corneal stromal cells (keratocytes), endogenous BMP-1 cleaved TSP-1, and the addition of exogenous BMP-1 enhanced cleavage, but this had no substantial effect on cell adhesion. Instead, processed TSP-1 promoted the differentiation of keratocytes into myofibroblasts and stimulated production of the myofibroblast marker α-SMA, consistent with the presence of processed TSP-1 in human corneal scars. Our results indicate that BMP-1 can both trigger the disruption of cell adhesion and stimulate TGF-ß signaling in TSP-1-rich microenvironments, which has important potential consequences for wound healing and tumor progression.


Assuntos
Proteína Morfogenética Óssea 1/metabolismo , Proteólise , Trombospondina 1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Proteína Morfogenética Óssea 1/genética , Adesão Celular , Linhagem Celular Tumoral , Humanos , Trombospondina 1/genética , Fator de Crescimento Transformador beta/genética , Xenopus laevis
11.
Int J Mol Sci ; 21(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629886

RESUMO

Although sulfur-rich thermal waters have ancestrally been used in the context of dermatological conditions, a global mapping of the molecular effects exerted by H2S on human keratinocytes is still lacking. To fill this knowledge gap, we subjected cultured human keratinocytes to distinct amounts of the non-gaseous hydrogen sulfur donor NaHS. We first checked that H2S accumulated in the cytoplasm of keratinocytes under our experimental conditions andused a combination of proteomics, genomics and biochemical approaches to unravel functionally relevant H2S targets in human keratinocytes. We found that the identified targets fall into two main categories: (i) the oxidative stress response molecules superoxide dismutase 2 (SOD2), NAD(P)H quinone dehydrogenase 1 (NQO1) and culin 3 (CUL3) and (ii) the chemokines interleukin-8 (IL-8) and CXCL2. Interestingly, NaHS also stimulated the caspase-1 inflammasome pathway, leading to increased secretion of the pro-inflammatory molecule interleukin-18 (IL-18). Interestingly, the secretion of interleukin-1 beta (IL-1ß) was only modestly impacted by NaHS exposure despite a significant accumulation of IL-1ß pro-form. Finally, we observed that NaHS significantly hampered the growth of human keratinocyte progenitors and stem cells cultured under clonogenic conditions or as epidermal cell sheets. We conclude that H2S exerts specific molecular effects on normal human keratinocytes.


Assuntos
Sulfeto de Hidrogênio/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Culina/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Inflamassomos , Inflamação/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Superóxido Dismutase/metabolismo
12.
Front Cell Dev Biol ; 8: 571948, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505957

RESUMO

Breast cancer is the most common cancer among women worldwide. Overweight and obesity are now recognized as established risk factors for this pathology in postmenopausal women. These conditions are also believed to be responsible for higher recurrence and mortality rates. Reciprocal interactions have been described between adipose and cancer cells. An adipose microenvironment favors a greater proliferation of cancer cells, their invasion and even resistance to anti-cancer treatments. In addition, the chronic low-grade inflammation observed in obese individuals is believed to amplify these processes. Among the cell types present in the breast, myoepithelial cells (MECs), located at the interface of the epithelial cells and the stroma, are considered "tumor suppressor" cells. During the transition from ductal carcinoma in situ to invasive cancer, disorganization or even the disappearance of MECs is observed, thereby enhancing the ability of the cancer cells to migrate. As the adipose microenvironment is now considered as a central actor in the progression of breast cancer, our objective was to evaluate if it could be involved in MEC functional modifications, leading to the transition of in situ to invasive carcinoma, particularly in obese patients. Through a co-culture model, we investigated the impact of human adipose stem cells from women of normal weight and obese women, differentiated or not into mature adipocytes, on the functionality of the MECs by measuring changes in viability, apoptosis, gene, and miRNA expressions. We found that adipose cells (precursors and differentiated adipocytes) could decrease the viability of the MECs, regardless of the original BMI. The adipose cells could also disrupt the expression of the genes involved in the maintenance of the extracellular matrix and to amplify the expression of leptin and inflammatory markers. miR-122-5p and miR-132-3p could also be considered as targets for adipose cells. The metabolite analyses revealed specific profiles that may be involved in the growth of neoplastic cells. All of these perturbations could thus be responsible for the loss of tumor suppressor status of MECs and promote the transition from in situ to invasive carcinoma.

13.
Stem Cells Int ; 2019: 2186728, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31320905

RESUMO

Mesenchymal stem cells (MSCs) represent alternative candidates to chondrocytes for cartilage engineering. However, it remains difficult to identify the ideal source of MSCs for cartilage repair since conditions supporting chondrogenic induction are diverse among published works. In this study, we characterized and evaluated the chondrogenic potential of MSCs from bone marrow (BM), Wharton's jelly (WJ), dental pulp (DP), and adipose tissue (AT) isolated and cultivated under serum-free conditions. BM-, WJ-, DP-, and AT-MSCs did not differ in terms of viability, clonogenicity, and proliferation. By an extensive polychromatic flow cytometry analysis, we found notable differences in markers of the osteochondrogenic lineage between the 4 MSC sources. We then evaluated their chondrogenic potential in a micromass culture model, and only BM-MSCs showed chondrogenic conversion. This chondrogenic differentiation was specifically ascertained by the production of procollagen IIB, the only type II collagen isoform synthesized by well-differentiated chondrocytes. As a pilot study toward cartilage engineering, we encapsulated BM-MSCs in hydrogel and developed an original method to evaluate their chondrogenic conversion by flow cytometry analysis, after release of the cells from the hydrogel. This allowed the simultaneous quantification of procollagen IIB and α10, a subunit of a type II collagen receptor crucial for proper cartilage development. This work represents the first comparison of detailed immunophenotypic analysis and chondrogenic differentiation potential of human BM-, WJ-, DP-, and AT-MSCs performed under the same serum-free conditions, from their isolation to their induction. Our study, achieved in conditions compliant with clinical applications, highlights that BM-MSCs are good candidates for cartilage engineering.

14.
Cell Tissue Bank ; 20(1): 49-59, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30719600

RESUMO

Corneal disease is the second cause of blindness in developing countries, where the number of corneal grafts needed by far exceeds the number available. In industrialized countries, although corneas are generally available for keratoplasty, onto inflamed and vascularized host beds they are often rejected despite immune-suppression. A non-immunogenic, transparent, cytocompatible stroma is therefore required, which can be lyophilized for long-term conservation. Decellularization methods were tested on porcine corneal stromas before validation on human corneas. Decellularization and lyophilization led to opacification of the stroma, which could be reversed by soaking in 100% glycerol. Cell-depleted transparized stromas were then lyophilized (LTDC) to allow their long-term conservation and water content was measured. The ultrastructure of LTDC corneas was examined by transmission electron microscopy (TEM). Histocompatibility antigens were undetectable on LTDC stromas by antibody staining. Finally, cytocompatibility of LTDC stromas was demonstrated on an ex vivo model of anterior lamellar keratoplasty. Differential staining was used to monitor colonization of LTDC stromas by cells from the receiving cornea. Only SDS-based decellularization produced acellular porcine stromas. The lowest SDS concentration tested (0.1%) was validated on human corneas. Unlike lyophilized corneas, LTDC stromas without residual water, express no histocompatibility markers, although TEM revealed the presence of cellular debris in an ultrastructural arrangement of collagen fibers very close to that of native corneas. This structure is compatible with colonization by cells from the receiver cornea in an ex vivo lamellar graft model. Our procedure produced non-immunogenic, transparent stromas with conserved ultrastructure compatible with long-term conservation.


Assuntos
Substância Própria/citologia , Transplante de Córnea/métodos , Liofilização/métodos , Engenharia Tecidual/métodos , Animais , Substância Própria/ultraestrutura , Antígenos de Histocompatibilidade/metabolismo , Humanos , Modelos Biológicos , Suínos , Termogravimetria
15.
Cell Transplant ; 27(2): 264-274, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29637812

RESUMO

Total bilateral limbal stem cell deficiency leading to loss of corneal clarity, potential vision loss, pain, photophobia, and keratoplasty failure cannot be treated by autologous limbal transplantation, and allogeneic limbal transplantation requires subsequent immunosuppressive treatment. Cultured autologous oral mucosal epithelial cells have been shown to be safe and effective alternatives. These cells can be transplanted on supports or without support after detachment from the culture dishes. Dispase, known for epidermal sheet detachment, is reported as not usable for oral mucosa. The objective was to find an optimized detachment method providing a sufficiently resistant and adhesive cultured oral mucosal epithelium (COME), which can be grafted without sutures. Enzymatic treatments (dispase or collagenase at different concentrations) were compared to enzyme-free mechanical detachment. Histological immunofluorescence (IF) and Western blotting (WB) were used to examine the impact on adhesion markers (laminin-332, ß1-integrin, and type VII collagen) and junctional markers (E-cadherin, P-cadherin). Finally, the COME ability to adhere to the cornea and produce a differentiated epithelium 15 d after grafting onto an ex vivo porcine stroma model were investigated by histology, IF, and transmission electron microscopy. Collagenase at 0.5 mg/mL and dispase at 5 mg/mL were selected for comparative study on adhesive expression marker by IF and WB showed that levels of basement membrane proteins and cell-cell and cell-matrix junction proteins were not significantly different between the 3 detachment methods. Collagenase 0.5 mg/mL was selected for the next step validation because of the better reproducibility, 100% success (vs. 33% with dispase 5 mg/mL). Grafted onto porcine de-epithelialized corneal stroma, collagenase 0.5 mg/mL detached COME were found to adhere, stratify, and continue to ensure renewal of the epithelium. For COME, collagenase 0.5 mg/mL enzymatic detachment was selected and validated on its resistance and adhesive marker expression as well as their anchorage onto our new ex vivo de-epithelialized stroma model.


Assuntos
Membrana Basal/citologia , Limbo da Córnea/patologia , Mucosa Bucal/citologia , Células-Tronco/citologia , Animais , Membrana Basal/ultraestrutura , Células Cultivadas , Doenças da Córnea/terapia , Humanos , Microscopia Eletrônica de Transmissão , Mucosa Bucal/ultraestrutura , Transplante de Células-Tronco/métodos , Células-Tronco/ultraestrutura , Suínos
16.
PLoS One ; 13(2): e0191571, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29389973

RESUMO

BACKGROUND: Obesity is a well-known risk factor of breast cancer in post-menopausal women that also correlates with a diminished therapeutic response. The influence of adipocytes and their secretome, i.e. adipokines, on the efficacy of hormone therapy has yet to be elucidated. METHODS: We investigated, ex vivo, whether mature adipocytes, differentiated from adipose stem cells of normal-weight (MA20) or obese (MA30) women, and their secretions, were able to counteract the effects of tamoxifen (Tx) which is known to decrease neoplastic cell proliferation. RESULTS: In a tridimensional model and in a model of co-culture, the anti-proliferative effect of Tx on MCF-7 cancer cells was counteracted by MA30. These two models highlighted two different specific gene expression profiles for genes encoding cytokines or involved in angiogenesis based on the adipocyte microenvironment and the treatment. Thus it notably showed altered expression of genes such as TNFα that correlated with IL-6. In addition, leptin, IL-6 and TNFα, at concentrations reflecting plasma concentrations in obese patients, decreased the anti-proliferative efficacy of 4-hydroxytamoxifen (a major active metabolite of Tx). CONCLUSIONS: These findings bring insights on adipocytes and mammary cancer cell interactions in Tx therapy, particularly in overweight/obese people. Indeed, patient' adipokine status would give valuable information for developing individual strategies and avoid resistance to treatment.


Assuntos
Adipócitos/patologia , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Obesidade/patologia , Tamoxifeno/farmacologia , Linhagem Celular , Feminino , Expressão Gênica , Humanos , Leptina/metabolismo , Células MCF-7 , Fator de Necrose Tumoral alfa/metabolismo
17.
Medicine (Baltimore) ; 96(19): e6885, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28489792

RESUMO

The purpose of this article is to examine outcomes of Descemet membrane endothelial keratoplasty (DMEK) performed with cornea bank (CB) prestripped tissue and surgeon stripped tissue (SST).This retrospective study examined subjects who underwent DMEK with CB or surgeon prepared tissue for Fuchs endothelial corneal dystrophy. Best-corrected visual acuity (BCVA), corneal thickness, endothelial cell count (ECC), and complications were examined before and throughout a 6-month postoperative period.Eleven CB and 22 SST subjects were included. Six months after surgery, BCVA was 20/20 or better in 36.4% of CB and 22.7% of SST subjects (P = .43). Median logMAR BCVA was 0.10 (0.00-0.20, 20/25) in group CB and 0.10 (0.10-0.30, 20/25) in group SST. Median preoperative corneal thickness was 614.0 µm (577.5-662.0 µm) and 658.0 µm (606.0-689.0 µm) in CB and SST subjects, respectively (P = .37). Six months after surgery, median corneal thickness was lower in the CB group (571.0 µm [478.0-592.0 µm]), than in the SST group (576.0 µm [531.0-607.0 µm], P = .02). At 6 months, median ECC was 1500.0 cell/mm (1321.5-2049.0 cell/mm, 41% decrease) in group CB and 1403.0 cell/mm (972.5-2010.7 cell/mm, 46% decrease) in group SST (P = .70). Rebubbling was required in 5 CB (45.5%) and 15 SST (68.2%) subjects (P = .39).Fuchs' dystrophy patients have good anatomic and functional DMEK results. Similar outcomes and complication rates occurred with eye bank and surgeon prepared donor tissue.


Assuntos
Lâmina Limitante Posterior , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Bancos de Olhos , Distrofia Endotelial de Fuchs/cirurgia , Idoso , Idoso de 80 Anos ou mais , Lâmina Limitante Posterior/patologia , Lâmina Limitante Posterior/cirurgia , Endotélio Corneano/patologia , Endotélio Corneano/cirurgia , Feminino , Distrofia Endotelial de Fuchs/patologia , Rejeição de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Complicações Pós-Operatórias , Estudos Retrospectivos , Cirurgiões , Resultado do Tratamento , Acuidade Visual
18.
Stem Cells Int ; 2017: 9289213, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28321259

RESUMO

Adipose-derived stem/stromal cells (ASCs) reside in the stromal vascular fraction (SVF) of adipose tissue (AT) and can be easily isolated. However, extraction of the SVF from lipoaspirate is a critical step in generating ASC, and semiautomated devices have been developed to enhance the efficacy and reproducibility of the outcomes and to decrease manipulation and contamination. In this study, we compared the reference method used in our lab for SVF isolation from lipoaspirate, with three medical devices: GID SVF-1™, Puregraft™, and Stem.pras®. Cell yield and their viability were evaluated as well as their phenotype with flow cytometry. Further on, we determined their proliferative potential using population doublings (PD), PD time (PDT), and clonogenicity assay (CFU-F). Finally, we checked their genetic stability using RT-qPCR for TERT mRNA assay and karyotyping as well as their multilineage potential including adipogenic, chondrogenic, and osteogenic differentiation. Our results demonstrate that all the devices allow the production of SVF cells with consistent yield and viability, in less time than the reference method. Expanded cells from the four methods showed no significant differences in terms of phenotype, proliferation capabilities, differentiation abilities, and genetic stability.

19.
Cell Tissue Bank ; 17(2): 225-32, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26934895

RESUMO

Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK "no touch" dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by "no touch" technique, allowing time saving, quality and security for surgeons.


Assuntos
Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Dissecação/métodos , Células Endoteliais/citologia , Bancos de Tecidos , Técnicas de Cultura de Tecidos/métodos , Adulto , Contagem de Células , Endotélio Corneano/citologia , Humanos , Reprodutibilidade dos Testes
20.
J Plast Reconstr Aesthet Surg ; 68(11): 1491-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282247

RESUMO

Soft tissue reconstruction is a challenge in plastic surgery, when replacing lost materials and correcting contour defects. Many permanent and temporary fillers have been used to restore the volume of these lesions, but often with poor results and even complications. Adipose-derived stem/stromal cells (ASCs) and adipose tissue engineering have been suggested as valuable alternatives. In order to inject these cultured cells, it was essential to find a suitable vehicle. The purpose of this study was to evaluate Cytocare(®), an injectable medical device, composed of hyaluronic acid plus amino acids, vitamins and mineral salts. First, ASC viability and bioavailability in the 3 different available Cytocare(®) formulations using the MTT test were assessed; then an animal experiment, testing the tolerance after intradermal injections of both Cytocare(®) alone and with ASCs was carried out. Our in vitro results demonstrate a high biocompatibility of Cytocare(®) resulting in a better viability of ASCs when cultured in Cytocare(®) compared to culture medium (p < 0.05, Mann and Whitney). Cytocare(®) also permits their bioavailability and proliferation, making it a potential transfer vehicle that can retain the cells before their integration around the recipient site. Finally, our animal experiment shows that the ASC + Cytocare(®) combination is well tolerated. In conclusion, Cytocare(®) can be used as a biocompatible scaffold for cultured ASCs in therapeutic treatments, ensuring ASC bioavailability, as well as evidence of excellent tolerance in nude mice.


Assuntos
Adipócitos/transplante , Tolerância Imunológica , Procedimentos de Cirurgia Plástica/métodos , Transplante de Células-Tronco/métodos , Células Estromais/transplante , Engenharia Tecidual/métodos , Adipócitos/imunologia , Tecido Adiposo/citologia , Tecido Adiposo/imunologia , Animais , Disponibilidade Biológica , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Teste de Materiais , Camundongos , Camundongos Nus , Células Estromais/imunologia
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