RÉSUMÉ
Patients with chronic hypoxia show a higher tumor incidence; however, no primary common cause has been recognized. Given the similarities between cellular reprogramming and oncogenic transformation, we directly compared these processes in human cells subjected to hypoxia. Mouse embryonic fibroblasts were employed as controls to compare transfection and reprogramming efficiency; human adipose-derived mesenchymal stem cells were employed as controls in human cells. Easily obtainable human peripheral blood mononuclear cells (PBMCs) were chosen to establish a standard protocol to compare cell reprogramming (into induced pluripotent stem cells (iPSCs)) and oncogenic focus formation efficiency. Cell reprogramming was achieved for all three cell types, generating actual pluripotent cells capable for differentiating into the three germ layers. The efficiencies of the cell reprogramming and oncogenic transformation were similar. Hypoxia slightly increased the reprogramming efficiency in all the cell types but with no statistical significance for PBMCs. Various PBMC types can respond to hypoxia differently; lymphocytes and monocytes were, therefore, reprogrammed separately, finding a significant difference between normoxia and hypoxia in monocytes in vitro. These differences were then searched for in vivo. The iPSCs and oncogenic foci were generated from healthy volunteers and patients with chronic obstructive pulmonary disease (COPD). Although higher iPSC generation efficiency in the patients with COPD was found for lymphocytes, this increase was not statistically significant for oncogenic foci. Remarkably, a higher statistically significant efficiency in COPD monocytes was demonstrated for both processes, suggesting that physiological hypoxia exerts an effect on cell reprogramming and oncogenic transformation in vivo in at least some cell types.
Sujet(s)
Transformation cellulaire néoplasique , Reprogrammation cellulaire , Cellules souches pluripotentes induites , Humains , Reprogrammation cellulaire/génétique , Cellules souches pluripotentes induites/métabolisme , Transformation cellulaire néoplasique/génétique , Transformation cellulaire néoplasique/anatomopathologie , Animaux , Souris , Hypoxie cellulaire , Agranulocytes/métabolisme , Agranulocytes/cytologie , Mâle , Femelle , Adulte d'âge moyen , Fibroblastes/métabolisme , Fibroblastes/anatomopathologie , Différenciation cellulaire/génétique , Sujet âgéRÉSUMÉ
PURPOSE: This study investigates immune cell (ICs) infiltration in advanced keratoconus patients undergoing autologous adipose-derived adult stem cell (ADASC) therapy with recellularized human donor corneal laminas (CL). METHODS: A prospective clinical trial included fourteen patients divided into three groups: G-1, ADASCs; G-2, decellularized CL (dCL); and G-3, dCL recellularized with ADASCs (ADASCs-rCL). Infiltrated ICs were assessed using in vivo confocal microscopy (IVCM) at 1,3,6, and12 months post-transplant. RESULTS: Infiltrated ICs, encompassing granulocytes and agranulocytes, were observed across all groups, categorized by luminosity, structure, and area. Stromal ICs infiltration ranged from 1.19% to 6.62%, with a consistent increase in group-related cell density (F = 10.68, P < .0001), independent of post-op time (F = 0.77, P = 0.511); the most substantial variations were observed in G-3 at 6 and 12 months (2.0 and 1.87-fold, respectively). Similarly, significant size increases were more group-dependent (F = 5.76, P < .005) rather than time-dependent (F = 2.84, P < .05); G-3 exhibited significant increases at 6 and 12 months (3.70-fold and 2.52-fold, respectively). A lamina-induced shift in IC size occurred (F = 110.23, P < .0001), primarily with 50-100 µm2 sizes and up to larger cells > 300µm2, presumably macrophages, notably in G-3, indicating a potential role in tissue repair and remodeling, explaining reductions in cells remnants < 50µm2. CONCLUSIONS: ADASCs-rCL therapy may lead to increased IC infiltration compared to ADASCs alone, impacting cell distribution and size due to the presence of the lamina. The findings reveal intricate immune patterns shaped by the corneal microenvironment and highlight the importance of understanding immune responses for the development of future therapeutic strategies.
RÉSUMÉ
Background: Iodine is required for the synthesis of thyroid hormone (TH), but its natural availability is limited. Dehalogenase1 (Dehal1) recycles iodine from mono- and diiodotyrosines (MIT, DIT) to sustain TH synthesis when iodine supplies are scarce, but its role in the dynamics of storage and conservation of iodine is unknown. Methods: Dehal1-knockout (Dehal1KO) mice were generated by gene trapping. The timing of expression and distribution was investigated by X-Gal staining and immunofluorescence using recombinant Dehal1-beta-galactosidase protein produced in fetuses and adult mice. Adult Dehal1KO and wild-type (Wt) animals were fed normal and iodine-deficient diets for 1 month, and plasma, urine, and tissues were isolated for analyses. TH status was monitored, including thyroxine, triiodothyronine, MIT, DIT, and urinary iodine concentration (UIC) using a novel liquid chromatography with tandem mass spectrometry method and the Sandell-Kolthoff (S-K) technique throughout the experimental period. Results: Dehal1 is highly expressed in the thyroid and is also present in the kidneys, liver, and, unexpectedly, the choroid plexus. In vivo transcription of Dehal1 was induced by iodine deficiency only in the thyroid tissue. Under normal iodine intake, Dehal1KO mice were euthyroid, but they showed negative iodine balance due to a continuous loss of iodotyrosines in the urine. Counterintuitively, the UIC of Dehal1KO mice is twofold higher than that of Wt mice, indicating that S-K measures both inorganic and organic iodine. Under iodine restriction, Dehal1KO mice rapidly develop profound hypothyroidism, while Wt mice remain euthyroid, suggesting reduced retention of iodine in the thyroids of Dehal1KO mice. Urinary and plasma iodotyrosines were continually elevated throughout the life cycles of Dehal1KO mice, including the neonatal period, when pups were still euthyroid. Conclusions: Plasma and urine iodotyrosine elevation occurs in Dehal1-deficient mice throughout life. Therefore, measurement of iodotyrosines predicts an eventual iodine shortage and development of hypothyroidism in the preclinical phase. The prompt establishment of hypothyroidism upon the start of iodine restriction suggests that Dehal1KO mice have low iodine reserves in their thyroid glands, pointing to defective capacity for iodine storage.
Sujet(s)
Hypothyroïdie , Iode , Souris , Animaux , Mono-iodotyrosine/métabolisme , Souris knockout , Iodide peroxidase/génétique , Hypothyroïdie/génétique , Marqueurs biologiques , Thyroxine , Iode/métabolismeRÉSUMÉ
Adipose-derived stem cells are a subtype of mesenchymal stem cell that offers the important advantage of being easily obtained (in an autologous manner) from low invasive procedures, rendering a high number of multipotent stem cells with the potential to differentiate into several cellular lineages, to show immunomodulatory properties, and to promote tissue regeneration by a paracrine action through the secretion of extracellular vesicles containing trophic factors. This secretome is currently being investigated as a potential source for a cell-free based regenerative therapy for human tissues, which would significantly reduce the involved costs, risks and law regulations, allowing for a broader application in real clinical practice. In the current article, we will review the existing preclinical and human clinical evidence regarding the use of such adipose-derived mesenchymal stem cells for the regeneration of the three main layers of the human cornea: the epithelium (derived from the surface ectoderm), the stroma (derived from the neural crest mesenchyme), and the endothelium (derived from the neural crest cells).
Sujet(s)
Cellules souches mésenchymateuses , Tissu adipeux , Cornée , Humains , Cellules souches multipotentes , Cellules souchesRÉSUMÉ
Corneal disease affects 12.5 million individuals worldwide, with 2 million new cases each year. The standard treatment consists of a corneal transplantation from a human donor; however, the worldwide demand significantly exceeds the available supply. Lamellar endothelial keratoplasty, the replacement of only the endothelial layer of the cornea, can partially solve the problem. Progressive efforts have succeeded in expanding hCECs; however, the ability to expand hCECs is still limited, and new sources of CECs are being sought. Crucial advances have been achieved by the directed differentiation of embryonic or induced pluripotent stem cells, but these cells have disadvantages, such as the use of oncogenes, and are still difficult to establish. We aimed to transfer such knowledge to obtain hCECs from adipose tissue-derived adult mesenchymal stem cells (ADSC) by modifying four previously published procedures. We present several protocols capable of the directed differentiation of human ADSCs to hCECs. In our hands, the protocol by Ali et al. was the best adapted to such differentiation in terms of efficiency, time, and financial cost; however, the protocol by Wagoner et al. was the best for CEC marker expression. Our results broaden the type of cells of autologous extraocular origin that could be employed in the clinical setting for corneal endothelial deficiency.
Sujet(s)
Techniques de culture cellulaire/méthodes , Maladies de la cornée/thérapie , Transplantation de cornée/méthodes , Endothélium de la cornée/cytologie , Cellules souches mésenchymateuses/cytologie , Adulte , Différenciation cellulaire/physiologie , Cellules cultivées , Maladies de la cornée/anatomopathologie , Endothélium de la cornée/métabolisme , Femelle , Humains , Cellules souches mésenchymateuses/métabolisme , Adulte d'âge moyen , Donneurs de tissus , Ingénierie tissulaire/méthodesRÉSUMÉ
Limbal stem cells (LSC) maintain the transparency of the corneal epithelium. Chemical burns lead the loss of LSC inducing an up-regulation of pro-inflammatory and pro-angiogenic factors, triggering corneal neovascularization and blindness. Adipose tissue-derived mesenchymal stem cells (AT-MSC) have shown promise in animal models to treat LSC deficiency (LSCD), but there are not studies showing their efficacy when primed with different media before transplantation. We cultured AT-MSC with standard medium and media used to culture LSC for clinical application. We demonstrated that different media changed the AT-MSC paracrine secretion showing different paracrine effector functions in an in vivo model of chemical burn and in response to a novel in vitro model of corneal inflammation by alkali induction. Treatment of LSCD with AT-MSC changed the angiogenic and inflammatory cytokine profile of mice corneas. AT-MSC cultured with the medium that improved their cytokine secretion, enhanced the anti-angiogenic and anti-inflammatory profile of the treated corneas. Those corneas also presented better outcome in terms of corneal transparency, neovascularization and histologic reconstruction. Priming human AT-MSC with LSC specific medium can potentiate their ability to improve corneal wound healing, decrease neovascularization and inflammation modulating paracrine effector functions in an in vivo optimized rat model of LSCD.
Sujet(s)
Cornée/cytologie , Maladies de la cornée/prévention et contrôle , Néovascularisation cornéenne/prévention et contrôle , Inflammation/prévention et contrôle , Cellules souches mésenchymateuses/cytologie , Régénération , Cicatrisation de plaie , Animaux , Différenciation cellulaire , Cellules cultivées , Cornée/métabolisme , Maladies de la cornée/anatomopathologie , Néovascularisation cornéenne/anatomopathologie , Humains , Inflammation/anatomopathologie , Cellules souches mésenchymateuses/métabolisme , Souris , RatsRÉSUMÉ
Historically, primordial germ cells (PGCs) have been a good model to study pluripotency. Despite their low numbers and limited accessibility in the mouse embryo, they can be easily and rapidly reprogrammed at high efficiency with external physicochemical factors and do not require transcription factor transfection. Employing this model to deepen our understanding of cell reprogramming, we specifically aimed to determine the relevance of Ca2+ signal transduction pathway components in the reprogramming process. Our results showed that PGC reprogramming requires a normal extracellular [Ca2+] range, in contrast to neoplastic or transformed cells, which can continue to proliferate in Ca2+-deficient media, differentiating normal reprogramming from neoplastic transformation. Our results also showed that a spike in extracellular [Ca2+] of 1-3 mM can directly reprogram PGC. Intracellular manipulation of Ca2+ signal transduction pathway components revealed that inhibition of classical Ca2+ and diacylglycerol (DAG)-dependent PKCs, or intriguingly, of only the novel DAG-dependent PKC, PKCε, were able to induce reprogramming. PKCε inhibition changed the metabolism of PGCs toward glycolysis, increasing the proportion of inactive mitochondria. This metabolic switch from oxidative phosphorylation to glycolysis is mediated by hypoxia-inducible factors (HIFs), given we found upregulation of both HIF1α and HIF2α in the first 48 hours of culturing. PKCε inhibition did not change the classical pluripotency gene expression of PGCs, Oct4, or Nanog. PKCε inhibition changed the histone acetylation of PGCs, with histones H2B, H3, and H4 becoming acetylated in PKCε-inhibited cultures (markers were H2BacK20, H3acK9, and H4acK5K8, K12, K16), suggesting that reprogramming by PKCε inhibition is mediated by histone acetylation.
RÉSUMÉ
The use of advanced therapies with stem cells to reconstruct the complex tissue of corneal stroma has gained interest in recent years. Besides, collagen-based scaffolds bioengineering has been offered as another alternative over the last decade. The outcomes of the first clinical experience with stem cells therapy on corneal stroma regeneration in patients with advanced keratoconus were recently reported. Patients were distributed into three experimental groups: Group 1 (G-1) patients underwent implantation of autologous adipose-derived adult stem cells (ADASCs) alone, Group 2 (G-2) received a 120 µm decellularized donor corneal stromal laminas, and Group 3 (G-3) received a 120 µm recellularized donor laminas with ADASCs. A follow up of 36 months of clinical data, and 12 months of confocal microscopy study was performed, the authors found significant clinical improvement in almost all studied mean values of primary and secondary outcomes. Corneal confocal microscopy demonstrated an increase in cell density in the host stroma, as well as in the implanted tissue. Using different approaches, allogenic small incision lenticule extraction (SMILE) implantation was applied in cases with advanced keratoconus. Some authors reported the implantation of SMILE intrastromal lenticules combined with accelerated collagen cross-linking. Others performed intrastromal implantation of negative meniscus-shaped corneal stroma lenticules. Others have compared the outcomes of penetrating keratoplasty (PKP) vs. small-incision Intralase femtosecond (IFS) intracorneal concave lenticule implantation (SFII). Femtosecond laser-assisted small incision sutureless intrasotromal lamellar keratoplasty (SILK) has been also investigated. The published evidence shows that the implantation of autologous ADASCs, decellularized or recellularized human corneal stroma, allogenic SMILE lenticules corneal inlay, and recombinant cross-linked collagen have shown initially to be potentially effective for the treatment of advanced keratoconus. In light of the present evidence available, it can be said that the era of corneal stromal regeneration therapy has been already started.
RÉSUMÉ
PURPOSE: To report the 3-year clinical outcomes of corneal stromal cell therapy consisting of the intrastromal implantation with autologous adipose-derived adult stem cells (ADASCs), and decellularized or ADASC-recellularized human donor corneal laminas in advanced keratoconus. METHODS: Fourteen patients were enrolled in 3 experimental groups. Group 1 (G-1) patients underwent implantation of ADASCs alone (3 × 106 cells/1 mL) (n = 5). Group 2 (G-2) patients received a 120-µm decellularized corneal stroma lamina (n = 5). Group 3 (G-3) patients received a 120-µm lamina recellularized with ADASCs (1 × 106 cells/1 mL) (n = 4). ADASCs were obtained by elective liposuction. Implantation was performed into a femtosecond pocket under topical anesthesia. RESULTS: At 3 years, a significant improvement of 1 to 2 logMAR lines in uncorrected distance visual acuity was observed in all groups. A statistically significant decrease in corrected distance visual acuity was obtained in G-2 and G-3 (P < 0.001) when compared with that of G-1. Rigid contact lens distance visual acuity showed a statistically significant worsening in G-2 (P < 0.001) compared with that of G-1. A statistically significant increase in central corneal thickness was observed in G-2 (P = 0.012) and G-3 (P < 0.001); in the Scheimpflug corneal topography, the thinnest point was observed in G-2 (P = 0.007) and G-3 (P = 0.001) when compared with that of G-1. CONCLUSIONS: Intrastromal implantation of ADASCs and decellularized or ADASC-recellularized human corneal stroma laminas did not have complications at 3 years. The technique showed a moderate improvement in (uncorrected distance visual acuity) and (corrected distance visual acuity) in advanced keratoconus.
Sujet(s)
Tissu adipeux/cytologie , Thérapie cellulaire et tissulaire , Stroma de la cornée/physiologie , Kératocône/thérapie , Transplantation de cellules souches mésenchymateuses , Régénération/physiologie , Adulte , Pachymétrie cornéenne , Topographie cornéenne , Femelle , Études de suivi , Humains , Kératocône/physiopathologie , Mâle , Études prospectives , Réfraction oculaire/physiologie , Médecine régénérative , Biomicroscopie , Transplantation autologue , Résultat thérapeutique , Acuité visuelle/physiologieRÉSUMÉ
Corneal grafting is one of the most common and successful forms of human tissue transplantation in the world, but the need for corneal grafting is growing and availability of human corneal donor tissue to fulfill this increasing demand is not assured worldwide. The stroma is responsible for many features of the cornea, including its strength, refractive power and transparency, so enormous efforts have been put into replicating the corneal stroma in the laboratory to find an alternative to classical corneal transplantation. Unfortunately this has not been yet accomplished due to the extreme difficulty in mimicking the highly complex ultrastructure of the corneal stroma, and none of the obtained substitutes that have been assayed has been able to replicate this complexity yet. In general, they can neither match the mechanical properties nor recreate the local nanoscale organization and thus the transparency and optical properties of a normal cornea. In this context, there is an increasing interest in cellular therapy of the corneal stroma using Induced Pluripotent Stem Cells (iPSCs) or mesenchymal stem cells (MSCs) from either ocular or extraocular sources, as they have proven to be capable of producing new collagen within the host stroma, modulate preexisting scars and enhance transparency by corneal stroma remodeling. Despite some early clinical data is already available, in the current article we will summary the available preclinical evidence about the topic corneal stroma regeneration. Both, in vitro and in vivo experiments in the animal model will be shown.
Sujet(s)
Maladies de la cornée/thérapie , Stroma de la cornée/physiologie , Régénération/physiologie , Transplantation de cellules souches , Animaux , Humains , Cellules souches pluripotentes induites/transplantation , Cellules souches mésenchymateuses/cytologieRÉSUMÉ
Corneal grafting is one of the most common forms of human tissue transplantation. The corneal stroma is responsible for many characteristics of the cornea. For these reasons, an important volume of research has been made to replicate the corneal stroma in the laboratory to find an alternative to classical corneal transplantation techniques.There is an increasing interest today in cell therapy of the corneal stroma using induced pluripotent stem cells or mesenchymal stem cells since these cells have shown to be capable of producing new collagen within the host stroma and even to improve its transparency.The first clinical experiment on corneal stroma regeneration in advanced keratoconus cases has been reported and included. Fourteen patients were randomized and enrolled into 3 experimental groups: (1) patients underwent implantation of autologous adipose-derived adult stem cells alone, (2) patients received decellularized donor corneal stroma laminas, and (3) patients received implantation of recellularized donor laminas with adipose-derived adult stem cells. Clinical improvement was detected with all cases in their visual, pachymetric, and topographic parameters of the operated corneas.Other recent studies have used allogenic SMILE implantation lenticule corneal inlays, showing also an improvement in different visual, topographic, and keratometric parameters.In the present report, we try to summarize the available preclinical and clinical evidence about the emerging topic of corneal stroma regeneration.
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Stroma de la cornée/anatomopathologie , Transplantation de cornée/méthodes , Kératocône/chirurgie , Acuité visuelle , Stroma de la cornée/chirurgie , Topographie cornéenne , Humains , Kératocône/diagnostic , Tomographie par cohérence optiqueRÉSUMÉ
Barraquer-Simons syndrome (BSS), a form of acquired partial lipodystrophy, is a rare condition characterized by gradual loss of adipose tissue from the upper body, keeping intact the white adipose tissue of the lower extremities. The etiology of BSS is not well understood, and clinical follow-up studies have not been assessed in these patients. Moreover, no histological studies have been conducted during the active phase of the disease, and complement system activation products have not been sought in the affected areas. The objective of this work was to analyze the clinical, immunological and histological events in an 11-year-old girl with BSS over a 5-year follow-up period. Clinical data were collected during six regular visits for a time period of 5 years. The circulating levels of C3, C3adesArg (a product released upon C3 activation), C4 and immunoglobulins (Ig) were quantified in serum while fat tissue from lipoatrophic areas was examined by immunohistochemical and immunofluorescence approaches. In her regular visits, no clinical or laboratory abnormalities had been observed in the patient, except for the progression of lipoatrophy linked to the C3 hypocomplementemia and the occurrence of C3 nephritic factor. Adipose tissue from the patient showed atrophied and dead adipocytes, an abnormal production of extracellular matrix, and a remarkable accumulation of infiltrating CD68 macrophages and adipocyte precursors (marked by c-Kit positiveness). Simultaneous detection of IgG, C3, C5a and C5b-9 proved the ongoing complement activity and complement-directed injury within the adipose tissue. Our results showed the first evidence that the complement system hyperactivation occurs within the adipose tissue and is linked with fat loss in patients with BSS.
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Lipodystrophie , Tissu adipeux , Enfant , Activation du complément , Facteur néphritique C3 , Femelle , HumainsRÉSUMÉ
Purpose: To report the corneal stroma cell density evolution identified by in vivo corneal confocal microscopy in humans using injected autologous adipose-derived adult stem cells (ADASCs) and corneal decellularized laminas in corneas with advanced keratoconus. Methods: Interventional prospective, consecutive, randomized, comparative series of cases. A total of 14 keratoconic patients were randomly distributed into three groups for three types of surgical interventions: group 1 (G-1), autologous ADASC implantation (n = 5); group 2 (G-2), decellularized human corneal stroma (n = 5); and group 3 (G-3), autologous ADASCs + decellularized human corneal stroma (n = 4). Results: A gradual and significant increase (P < 0.001) was observed in the cellularity in the anterior and posterior stroma of patients in G-1, G-2, and G-3 a year after the surgery in comparison with the preoperative density level. The same result was observed at the mid-corneal stroma in G-1 and at the anterior and posterior surfaces and within the laminas in G-2 and G-3. The cell density of patients receiving ADASC recellularized laminas (G-3) was statistically significantly higher (P = 0.011) at the anterior surface and within the lamina (P = 0.029) and at the posterior surface than in those implanted only with decellularized laminas (G-2). Conclusions: A significant increase in cell density occurred up to 1 postoperative year at the corneal stroma following the implantation of ADASCs alone, as well as in those cases implanted with decellularized and recellularized laminas at the different levels of the analysis. However, this increase was significantly higher in the ADASC recellularized laminas.
Sujet(s)
Kératocytes cornéens/cytologie , Stroma de la cornée/cytologie , Kératocône/thérapie , Transplantation de cellules souches mésenchymateuses , Cellules souches mésenchymateuses/cytologie , Adulte , Numération cellulaire , Survie cellulaire/physiologie , Pachymétrie cornéenne , Stroma de la cornée/transplantation , Topographie cornéenne , Femelle , Humains , Kératocône/imagerie diagnostique , Kératocône/anatomopathologie , Mâle , Microscopie confocale , Adulte d'âge moyen , Études prospectives , Tomographie par cohérence optique , Jeune adulteRÉSUMÉ
OBJECTIVE: We aimed to investigate the functionality of human decellularized stromal laminas seeded with cultured human corneal endothelial cells as a tissue engineered endothelial graft (TEEK) construct to perform endothelial keratoplasty in an animal model of corneal endothelial damage. METHODS: Engineered corneal endothelial grafts were constructed by seeding cultured human corneal endothelial cell (hCEC) suspensions onto decellularized human corneal stromal laminas with various coatings. The functionality and survival of these grafts with cultured hCECs was examined in a rabbit model of corneal endothelial damage after central descemetorhexis. Rabbits received laminas with and without hCECs (TEEK and control group, respectively). RESULTS: hCEC seeding over fibronectin-coated laminas provided an optimal and consistent endothelial cell count density and polygonal shape on the decellularized laminas, showing active pump fuction. Surgery was performed uneventfully as standard Descemet stripping automated endothelial keratoplasty (DSAEK). Corneal transparency gradually recovered in the TEEK group, whereas haze and edema persisted for up to 4 weeks in the controls. Histologic examination showed endothelial cells of human origin covering the posterior surface of the graft in the TEEK group. CONCLUSIONS: Grafting of decellularized stroma carriers re-surfaced with human corneal endothelial cells ex vivo can be a readily translatable method to improve visual quality in corneal endothelial diseases.
Sujet(s)
Lésions de la cornée/thérapie , Stroma de la cornée/cytologie , Transplantation de cornée/méthodes , Kératoplastie endothéliale automatisée par le stripping de Descemet/méthodes , Endothélium de la cornée/cytologie , Ingénierie tissulaire/méthodes , Adolescent , Adulte , Animaux , Études cas-témoins , Cellules cultivées , Stroma de la cornée/transplantation , Modèles animaux de maladie humaine , Cellules endothéliales/cytologie , Endothélium de la cornée/transplantation , Femelle , Survie du greffon , Humains , Mâle , Lapins , Résultat thérapeutique , Jeune adulteRÉSUMÉ
The liver centralizes the systemic metabolism and thus controls and modulates the functions of the central and peripheral nervous systems, the immune system, and the endocrine system. In addition, the liver intervenes between the splanchnic and systemic venous circulation, determining an abdominal portal circulatory system. The liver displays a powerful regenerative potential that rebuilds the parenchyma after an injury. This regenerative mission is mainly carried out by resident liver cells. However, in many cases this regenerative capacity is insufficient and organ failure occurs. In normal livers, if the size of the liver is at least 30% of the original volume, hepatectomy can be performed safely. In cirrhotic livers, the threshold is 50% based on current practice and available data. Typically, portal vein embolization of the part of the liver that is going to be resected is employed to allow liver regeneration in two-stage liver resection after portal vein occlusion (PVO). However, hepatic resection often cannot be performed due to advanced disease progression or because it is not indicated in patients with cirrhosis. In such cases, liver transplantation is the only treatment possibility, and the need for transplantation is the common outcome of progressive liver disease. It is the only effective treatment and has high survival rates of 83% after the first year. However, donated organs are becoming less available, and mortality and the waiting lists have increased, leading to the initiation of living donor liver transplantations. This type of transplant has overall complications of 38%. In order to improve the treatment of hepatic injury, much research has been devoted to stem cells, in particular mesenchymal stem cells (MSCs), to promote liver regeneration. In this review, we will focus on the advances made using MSCs in animal models, human patients, ongoing clinical trials, and new strategies using 3D organoids.
RÉSUMÉ
PURPOSE: This study evaluated 1-year safety and efficacy outcomes of corneal stroma cell therapy. Therapy consisted of implanting autologous adipose-derived adult stem cells (ADASc) with or without sheets of decellularized donor human corneal stroma within the stroma of patients with advanced keratoconus. DESIGN: This was a prospective interventional non-randomized series of cases. METHODS: Fourteen consecutive patients were selected and divided into 3 experimental groups. Group A patients underwent implantation of autologous ADASc alone (3 × 106 cells/1 mL) (n = 5). Group B patients received decellularized donor 120-µm-thick corneal stroma lamina alone (n = 5). Group C patients had implantation of recellularized donor lamina with 1 × 106 autologous ADASc plus another 1 × 106 cells/1 mL at the time of the surgery (n = 4). Autologous ADASc were obtained by elective liposuction. Implantation was performed in the corneal stroma through a femtosecond-assisted 9.5-mm diameter lamellar dissection with the patient under topical anesthesia. Twelve months of follow-up data are presented. RESULTS: No complications were observed during the 1-year follow-up, and full corneal transparency was recovered within 3 months in all patients. No patient lost lines of visual acuity. Corrected distance visual acuity improved 0.231, 0.264, and 0.094 Snellen lines in groups 1, 2, and 3, respectively. In group 1, refractive parameters showed an overall stability, whereas in groups 2 and 3, sphere improved 2.35 diopter (D) and 0.625 D, respectively. Anterior keratometry remained stable (group 1) and improved in groups 2 and 3 (mean improvement of 2D). Corneal aberrometry improved significantly. In optical coherence tomography scans, corneal thickness showed a mean improvement of 14.5 µm (group 1) and 116.4 µm (groups 2 and 3) in the central thickness, and new collagen production was observed at the surgical plane (group 1). Confocal biomicroscopy confirmed the host recellularization of the implanted laminas. CONCLUSIONS: Intrastromal implantation of autologous ADASc and decellularized human corneal stroma did not show complications at 1 year of follow-up and were moderately effective for the treatment of advanced keratoconus. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.
Sujet(s)
Thérapie cellulaire et tissulaire/méthodes , Stroma de la cornée/chirurgie , Kératocône/thérapie , Procédures de chirurgie ophtalmologique/méthodes , Transplantation de cellules souches/méthodes , Acuité visuelle , Adulte , Stroma de la cornée/cytologie , Topographie cornéenne , Femelle , Études de suivi , Humains , Kératocône/diagnostic , Mâle , Adulte d'âge moyen , Études prospectives , Facteurs temps , Tomographie par cohérence optique , Résultat thérapeutique , Jeune adulteRÉSUMÉ
Acquired generalized lipodystrophy (AGL) is a rare condition characterized by an altered distribution of adipose tissue and predisposition to develop hepatic steatosis and fibrosis, diabetes, and hypertriglyceridemia. Diagnosis of AGL is based on the observation of generalized fat loss, autoimmunity and lack of family history of lipodystrophy. The pathogenic mechanism of fat destruction remains unknown but evidences suggest an autoimmune origin. Anti-adipocyte antibodies have been previously reported in patients with AGL, although their involvement in the pathogenesis has been poorly studied and the autoantibody target/s remain/s to be identified. Using a combination of immunochemical and cellular studies, we investigated the presence of anti-adipocyte autoantibodies in patients with AGL, acquired partial lipodystrophy, localized lipoatrophy due to intradermic insulin injections or systemic lupus erythematosus. Moreover, the impact of anti-adipocyte autoantibodies from AGL patients was assessed in cultured mouse preadipocytes. Following this approach, we identified anti-perilipin 1 IgG autoantibodies in the serum of patients with autoimmune variety-AGL, but in no other lipodystrophies tested. These autoantibodies altered the ability of perilipin 1 to regulate lipolysis in cultured preadipocytes causing abnormal, significantly elevated basal lipolysis. Our data provide strong support for the conclusion that perilipin 1 autoantibodies are a cause of generalized lipodystrophy in these patients.
Sujet(s)
Adipocytes/immunologie , Autoanticorps/immunologie , Lipodystrophie généralisée congénitale/immunologie , Périlipine-1/immunologie , Cellules 3T3-L1 , Adipocytes/cytologie , Adolescent , Adulte , Animaux , Autoanticorps/sang , Marqueurs biologiques/sang , Cellules cultivées , Enfant , Femelle , Humains , Gouttelettes lipidiques/immunologie , Gouttelettes lipidiques/métabolisme , Lipodystrophie généralisée congénitale/sang , Lipodystrophie généralisée congénitale/diagnostic , Lipolyse/immunologie , Mâle , Souris , Adulte d'âge moyen , Périlipine-1/métabolismeRÉSUMÉ
PURPOSE: This phase 1 study seeks to preliminarily evaluate the safety and efficacy of decellularized human corneal stromal lamina transplantation with or without autologous adipose-derived adult stem cell recellularization within the corneal stroma of patients with advanced keratoconus. DESIGN: Phase 1 clinical trial. METHODS: Femtosecond-assisted 120-µm thickness and 9-mm diameter laminas were obtained from the anterior stroma of human donor corneas and decellularized with a sodium dodecyl sulfate solution. Autologous adipose-derived adult stem cells were obtained by elective liposuction and cultured onto both sides of the lamina. Five patients received the decellularized lamina alone and 4 patients the recellularized lamina into a femtosecond-assisted 9.5-mm diameter lamellar pocket under topical anesthesia. The total duration of follow-up was 6 months. RESULTS: No case showed clinical haze or scarring by month 3. Six months after surgery, patients showed a general improvement of all visual parameters, with a mean unaided visual acuity from 0.109 to 0.232 (P = .05) and corrected distance visual acuity from 0.22 to 0.356 (P = .068). Refractive sphere improved in all patients (from -4.55 diopters [D] to -2.69 D; P = .017), but refractive cylinder remained stable (from -2.83 to -2.61; P = .34). An improvement tendency of all anterior keratometric values was observed. A mean improvement of 120 µm in all thickness parameters was confirmed (P = .008), as well as an improvement in the spherical aberration (P = .018), coma (P = .23) and total higher order aberrations (P = .31). No significant differences among groups were detected. CONCLUSIONS: Decellularized human corneal stromal laminas transplantation seems safe and moderately effective for advanced keratoconus. Potential benefits of its recellularization with autologous adipose-derived adult stem cells remains unclear.
Sujet(s)
Stroma de la cornée/anatomopathologie , Topographie cornéenne/méthodes , Transplantation de cornée/méthodes , Kératocône/chirurgie , Transplantation de cellules souches/méthodes , Acuité visuelle , Adulte , Cellules cultivées , Pachymétrie cornéenne , Stroma de la cornée/transplantation , Femelle , Études de suivi , Humains , Kératocône/anatomopathologie , Mâle , Adulte d'âge moyen , Études prospectives , Réfraction oculaire , Indice de gravité de la maladie , Cellules souches/cytologie , Facteurs temps , Tomographie par cohérence optique , Transplantation autologue , Résultat thérapeutique , Jeune adulteRÉSUMÉ
BACKGROUND: Gestational diabetes mellitus (GDM) prevalence is increasing and becoming a major public health concern. Whether a Mediterranean diet can help prevent GDM in unselected pregnant women has yet to be studied. METHODS: We conducted a prospective, randomized controlled trial to evaluate the incidence of GDM with two different dietary models. All consecutive normoglycemic (<92 mg/dL) pregnant women at 8-12 gestational weeks (GW) were assigned to Intervention Group (IG, n = 500): MedDiet supplemented with extra virgin olive oil (EVOO) and pistachios; or Control Group (CG, n = 500): standard diet with limited fat intake. Primary outcome was to assess the effect of the intervention on GDM incidence at 24-28 GW. Gestational weight gain (GWG), pregnancy-induced hypertension, caesarean section (CS), preterm delivery, perineal trauma, small and large for gestational age (SGA and LGA) and admissions to neonatal intensive care unit were also assessed. Analysis was by intention-to-treat. RESULTS: A total of 874 women completed the study (440/434, CG/IG). According to nutritional questionnaires and biomarker analysis, women in the IG had a good adherence to the intervention. 177/874 women were diagnosed with GDM, 103/440 (23.4%) in CG and 74/434(17.1%) in IG, p = 0.012. The crude relative risk (RR) for GDM was 0.73 (95% CI: 0.56-0.95; p = 0.020) IG vs CG and persisted after adjusted multivariable analysis, 0.75(95% CI: 0.57-0.98; p = 0.039). IG had also significantly reduced rates of insulin-treated GDM, prematurity, GWG at 24-28 and 36-38 GW, emergency CS, perineal trauma, and SGA and LGA newborns (all p<0.05). CONCLUSIONS: An early nutritional intervention with a supplemented MedDiet reduces the incidence of GDM and improves several maternal and neonatal outcomes.
Sujet(s)
Diabète gestationnel/diétothérapie , Régime méditerranéen , Huile d'olive/administration et posologie , Pistacia , Adulte , Diabète gestationnel/épidémiologie , Femelle , Humains , Incidence , Nouveau-né , Mode de vie , Grossesse , Issue de la grossesse , Études prospectivesRÉSUMÉ
Obstructive sleep apnoea (OSA) is associated with cancer incidence and mortality. The contribution of the immune system appears to be crucial; however, the potential role of monocytes and natural killer (NK) cells remains unclear.Quantitative reverse transcriptase PCR, flow cytometry and in vitro assays were used to analyse the phenotype and immune response activity in 92 patients with OSA (60 recently diagnosed untreated patients and 32 patients after 6â months of treatment with continuous positive airway pressure (CPAP)) and 29 healthy volunteers (HV).We determined that monocytes in patients with OSA exhibit an immunosuppressive phenotype, including surface expression of glycoprotein-A repetitions predominant protein (GARP) and transforming growth factor-ß (TGF-ß), in contrast to those from the HV and CPAP groups. High levels of TGF-ß were detected in OSA sera. TGF-ß release by GARP+ monocytes impaired NK cytotoxicity and maturation. This altered phenotype correlated with the hypoxic severity clinical score (CT90). Reoxygenation eventually restored the altered phenotypes and cytotoxicity.This study demonstrates that GARP+ monocytes from untreated patients with OSA have an NK-suppressing role through their release of TGF-ß. Our findings show that monocyte plasticity immunomodulates NK activity in this pathology, suggesting a potential role in cancer incidence.