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1.
Mol Vis ; 28: 178-191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36274818

RESUMO

Purpose: In our earlier study, we identified hsa-miR-150-5p as a highly expressed miRNA in enriched corneal epithelial stem cells (CESCs). In this study, we aimed to understand the molecular regulatory function of hsa-miR-150-5p in association with the maintenance of stemness in CESCs. Methods: The target mRNAs of hsa-miR-150-5p were predicted and subjected to pathway analysis to identify targets for functional studies. Primary cultured limbal epithelial cells were transfected with hsa-miR-150-5p mimic, inhibitor, or scrambled sequence using Lipofectamine 3000. The transfected cells were analyzed to determine (i) their colony-forming potential; (ii) the expression levels of stem cell (SC) markers/transcription factors (ABCG2, NANOG, OCT4, KLF4, and ΔNp63), the differentiation marker (Cx43), and the hsa-miR-150-5p predicted targets (JARID2, INHBA, AKT3, and CTNNB1) by qPCR; and (iii) the expression levels of ABCG2, p63α, Cx43, JARID2, AKT3, p-AKT3, ß-catenin, and active ß-catenin by immunofluorescence staining and/or western blotting. Results: The ectopic expression level of hsa-miR-150-5p increased the colony-forming potential (8.29% ± 0.47%, p < 0.001) with the ability to form holoclone-like colonies compared with the control (1.8% ± 0.47%). The mimic-treated cells had higher expression levels of the SC markers but reduced expression levels of Cx43 and the targets of hsa-miR-150-5p that are involved in the Wnt-ß-catenin signaling pathway. The expression levels of ß-catenin and active ß-catenin in the inhibitor-transfected cells were higher than those in the control cells, and the localized nuclear expression indicated the activation of Wnt signaling. Conclusions: Our results indicate a regulatory role for hsa-miR-150-5p in the maintenance of CESCs by inhibiting the Wnt signaling pathway.


Assuntos
MicroRNAs , Via de Sinalização Wnt , Humanos , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo , Conexina 43/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Células Epiteliais/metabolismo , Células-Tronco/metabolismo
2.
Exp Eye Res ; 209: 108690, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34216616

RESUMO

The integrity of innermost layer of the cornea, the corneal endothelium, is key to sustaining corneal transparency. Therefore, disease or injury causing loss or damage to the corneal endothelial cell population may threaten vision. Transplantation of corneal tissue is the standard treatment used to replace malfunctioning corneal endothelial cells. However, this surgery is dependent upon donor tissue, which is limited in supply. Hence, tissue engineers have attempted to construct alternative transplantable tissues or cell therapies to alleviate this problem. Nevertheless, the intrinsic non-dividing nature of corneal endothelial cells continues to foil scientists in their attempts to yield large numbers of cells in the laboratory for use in such novel therapies. Interestingly, the contribution of the biomechanical properties of the underlying extracellular matrix (ECM) on cell division, tissue development and maintenance has been extensively investigated in other many cell types. However, the impact of biomechanics on corneal endothelial cell behaviour is relatively unexplored. Here, we describe contemporary tissue engineering solutions aimed at circumventing donor tissue scarcity. We review the ECM structure and biomechanical features of corneal endothelial cells. We discuss the alterations of ECM in endothelial disease development and progression and point out the role of ECM in developing a tissue-engineered corneal endothelium. We highlight the main biomechanical cues, including topographical and mechanical features, that impact cellular behaviors. Finally, we discuss the influence of biomechanical cues on cell and tissue development, and how corneal endothelial cells response to individual biomechanical stimuli in tissue engineering, which have implications for designing an engineered endothelium and maintaining cell function.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Transplante de Córnea/métodos , Lâmina Limitante Posterior/citologia , Endotélio Corneano/fisiopatologia , Engenharia Tecidual/métodos , Células Cultivadas , Endotélio Corneano/patologia , Humanos
3.
Exp Eye Res ; 197: 108063, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32417262

RESUMO

Limbal epithelial stem cells are required for the maintenance and repair of the corneal epithelial surface. The difficulty in obtaining human corneal tissue for research purposes means that animal models for studying the corneal and limbal epithelium are extremely useful. Porcine corneal tissue represents an attractive experimental model, however, functional analysis of the limbal epithelial cell population is needed to validate the use of this tissue. Single cell clonal analysis revealed that holoclone-generating cells were enriched in the limbus as compared with the central cornea (38.3% vs 8.3%) and that label-retaining cells were also enriched in the limbus and compared with the central cornea (44.7 ± 6.4 vs 4.7 ± 1.5). Furthermore, it was demonstrated that in a 3D-printed organ culture system, porcine tissue was capable of maintaining and healing the corneal epithelium. Ki67 staining of corneal sections revealed that in response to central epithelial wounding, a greater proportion of progenitors in the basal limbal epithelium enter an actively dividing state. The authors present a comprehensively validated model system for studying the interactions between limbal niche factors and limbal epithelial stem cell fate.


Assuntos
Lesões da Córnea/patologia , Epitélio Corneano/patologia , Limbo da Córnea/patologia , Células-Tronco/patologia , Cicatrização , Animais , Células Cultivadas , Modelos Animais de Doenças , Epitélio Corneano/lesões , Humanos , Limbo da Córnea/lesões , Técnicas de Cultura de Órgãos , Reprodutibilidade dos Testes , Suínos
4.
Exp Eye Res ; 197: 108074, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32502532

RESUMO

Limbal function is a key determinant of corneal epithelial integrity. Lineage tracing studies in mice have highlighted that the centripetal movement of epithelial progenitors from the limbus drives both the steady-state maintenance of the corneal epithelium and its regeneration following injury. It is well established that this is facilitated by a population of limbal epithelial stem cells within the limbus. It is becoming increasingly apparent that the behaviour of these stem cells and their ability to respond to the needs of the tissue are closely linked to their immediate microenvironment - the stem cell niche. Increasing understanding of the structural features of this niche and the signalling networks that they coordinate is required to enhance the therapeutic application of these cells in the treatment of limbal stem cell deficiency. Importantly, an improved characterisation of the hierarchy of limbal epithelial progenitors using both new and old putative markers will enable a greater appreciation for the effects of many of these limbal niche factors on stem cell fate.


Assuntos
Doenças da Córnea/patologia , Epitélio Corneano/patologia , Limbo da Córnea/patologia , Animais , Diferenciação Celular , Proliferação de Células , Doenças da Córnea/metabolismo , Humanos , Células-Tronco/citologia
5.
Am J Hum Genet ; 98(1): 75-89, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26749309

RESUMO

Congenital hereditary endothelial dystrophy 1 (CHED1) and posterior polymorphous corneal dystrophy 1 (PPCD1) are autosomal-dominant corneal endothelial dystrophies that have been genetically mapped to overlapping loci on the short arm of chromosome 20. We combined genetic and genomic approaches to identify the cause of disease in extensive pedigrees comprising over 100 affected individuals. After exclusion of pathogenic coding, splice-site, and copy-number variations, a parallel approach using targeted and whole-genome sequencing facilitated the identification of pathogenic variants in a conserved region of the OVOL2 proximal promoter sequence in the index families (c.-339_361dup for CHED1 and c.-370T>C for PPCD1). Direct sequencing of the OVOL2 promoter in other unrelated affected individuals identified two additional mutations within the conserved proximal promoter sequence (c.-274T>G and c.-307T>C). OVOL2 encodes ovo-like zinc finger 2, a C2H2 zinc-finger transcription factor that regulates mesenchymal-to-epithelial transition and acts as a direct transcriptional repressor of the established PPCD-associated gene ZEB1. Interestingly, we did not detect OVOL2 expression in the normal corneal endothelium. Our in vitro data demonstrate that all four mutated OVOL2 promoters exhibited more transcriptional activity than the corresponding wild-type promoter, and we postulate that the mutations identified create cryptic cis-acting regulatory sequence binding sites that drive aberrant OVOL2 expression during endothelial cell development. Our data establish CHED1 and PPCD1 as allelic conditions and show that CHED1 represents the extreme of what can be considered a disease spectrum. They also implicate transcriptional dysregulation of OVOL2 as a common cause of dominantly inherited corneal endothelial dystrophies.


Assuntos
Alelos , Distrofias Hereditárias da Córnea/genética , Mutação , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Sequência de Bases , DNA , Feminino , Humanos , Masculino , Linhagem , Homologia de Sequência do Ácido Nucleico
7.
Exp Eye Res ; 146: 83-94, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26704459

RESUMO

The transplantation of limbal epithelial stem cells (LESCs) cultured in vitro is a great advance in the treatment of patients suffering from LESC deficiency. However, the optimal technique for LESC isolation from a healthy limbal niche has not yet been established. Our aim was to determine which isolation method renders the highest recovery of functional LESCs from the human limbus. To achieve this purpose, we compared limbal primary cultures (LPCs) obtained from explants and cell suspensions on plastic culture plates. Cell morphology was observed by phase contrast and transmission electron microscopy. LESC, corneal epithelial cell, fibroblast, endothelial cell, melanocyte, and dendritic cell markers were analyzed by real time by reverse transcription polymerase chain reaction and/or immunofluorescence. In addition, colony forming efficiency (CFE) and the presence of holoclones, meroclones, and paraclones were studied. We observed that LPC cells obtained from both methods had cuboidal morphology, desmosomes, and prominent intermediate filaments. The expression of LESC markers (K14, K15, ABCG2, p63α) was similar or higher in LPCs established through cell suspensions, except the expression of p63α mRNA, and there were no significant differences in the expression of corneal epithelial markers (K3, K12). Endothelial cell (PECAM), melanocyte (MART-1), and dendritic cell (CD11c) proteins were not detected, while fibroblast-protein (S100A4) was detected in all LPCs. The CFE was significantly higher in LPCs from cell suspensions. Cells from confluent LPCs produced by explants generated only paraclones (100%), while the percentage of paraclones from LPCs established through cell suspensions was 90% and the remaining 10% were meroclones. In conclusion, LPCs established from cell suspensions have a cell population richer in functional LESCs than LPCs obtained from explants. These results suggest that in a clinical situation in which it is possible to choose between either of the isolation techniques from the donor limbal tissue, then the cell suspension is probably the best option as long as the cells are expanded following our culture conditions.


Assuntos
Técnicas de Cultura de Células/métodos , Epitélio Corneano/ultraestrutura , Limbo da Córnea/ultraestrutura , Células-Tronco/ultraestrutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Separação Celular , Células Cultivadas , Epitélio Corneano/metabolismo , Feminino , Humanos , Limbo da Córnea/metabolismo , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Células-Tronco/metabolismo , Doadores de Tecidos
8.
Exp Eye Res ; 138: 70-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26142953

RESUMO

Human limbal epithelial stem cells (LESCs) are essential for the maintenance of the corneal epithelium of the ocular surface. LESCs are located within limbal crypts between the palisades of Vogt in the limbus; the interface between the peripheral cornea and conjunctiva. The limbal crypts have been proposed as a LESC niche owing to their support of epithelial cells, which can form holoclone colonies in vitro. Closely associated with the limbal crypts is a concentrated population of melanocytes. The anatomical location and close proximity to putative LESC suggests that melanocytes might play a role in maintenance of these stem cells in the niche. The aim of this study was to assess the ability of human limbal melanocytes (hLM) to support the expansion of human limbal epithelial cells (LECs) in vitro as an indicator of functional cell-cell interaction. After observing that hLM co-localize with clusters of compact epithelial cells in the native limbal crypts, hLM were isolated from crypt-rich cadaveric limbal biopsies and used as feeders for the culture of LECs. Interestingly, LECs grown on mitotically active hLM were able to generate large epithelial colonies that contained small and compact cells with morphological stem cell characteristics. Immunocytochemistry revealed that LECs expanded on hLM were positive for the expression of the putative stem cell markers CK15, Bmi-1 and p63α and negative for the marker of terminal cell differentiation CK3. LECs and hLM were finally co-cultured on RAFT (real architecture for 3D tissue) collagen tissue equivalents. In 3D co-cultures, hLM promoted multi-layering of the epithelial sheet in which basal cells were maintained in an undifferentiated state. Taken together, these observations suggest melanocytes could play an important role in the maintenance of LESCs in the native human limbal stem cell niche.


Assuntos
Epitélio Corneano/citologia , Limbo da Córnea/citologia , Melanócitos/fisiologia , Nicho de Células-Tronco/fisiologia , Células-Tronco/citologia , Biomarcadores , Comunicação Celular/fisiologia , Contagem de Células , Técnicas de Cocultura , Epitélio Corneano/metabolismo , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Limbo da Córnea/metabolismo , Microscopia Eletrônica de Transmissão , Células-Tronco/metabolismo , Doadores de Tecidos , Engenharia Tecidual
9.
Exp Eye Res ; 127: 196-205, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25108221

RESUMO

Limbal epithelial stem cell deficiency can cause blindness but may be treated by human limbal epithelial cell (hLE) transplantation, normally on human amniotic membrane. Clinical outcomes using amnion can be unreliable and so we have developed an alternative tissue equivalent (TE), RAFT (Real Architecture for 3D Tissue), which supports hLE expansion, and stratification when airlifted. Human limbal fibroblasts (hLF) may be incorporated into RAFT TEs, where they support overlying hLE and improve phenotype. However, the impact of neither airlifting nor hLF on hLE function has been investigated. hLE on RAFT TEs (±hLF and airlifting) were wounded using heptanol and re-epithelialisation (fluorescein diacetate staining), and percentage putative stem cell marker p63α and proliferative marker Ki67 expression (wholemount immunohistochemistry), measured. Airlifted, hLF- RAFT TEs were unable to close the wound and p63α expression was 7 ± 0.2% after wounding. Conversely, non-airlifted, hLF- RAFT TEs closed the wound within 9 days and p63α expression was higher at 22 ± 5% (p < 0.01). hLE on both hLF- and hLF+ RAFT TEs (non-airlifted) closed the wound and p63α expression was 26 ± 8% and 36 ± 3% respectively (ns). Ki67 expression by hLE increased from 1.3 ± 0.5% before wounding to 7.89 ± 2.53% post-wounding for hLF- RAFT TEs (p < 0.01), and 0.8 ± 0.08% to 17.68 ± 10.88% for hLF+ RAFT TEs (p < 0.05), suggesting that re-epithelialisation was a result of proliferation. These data suggest that neither airlifting nor hLF are necessarily required to maintain a functional epithelium on RAFT TEs, thus simplifying and shortening the production process. This is important when working towards clinical application of regenerative medicine products.


Assuntos
Células Epiteliais/citologia , Epitélio Corneano/citologia , Fibroblastos/citologia , Limbo da Córnea/citologia , Cicatrização/fisiologia , Animais , Biomarcadores/metabolismo , Contagem de Células , Técnicas de Cultura de Células , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Células Epiteliais/metabolismo , Epitélio Corneano/metabolismo , Heptanol/toxicidade , Humanos , Limbo da Córnea/metabolismo , Microscopia Confocal , Técnicas de Cultura de Órgãos , Reepitelização , Suínos , Doadores de Tecidos , Engenharia Tecidual , Alicerces Teciduais , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
10.
Expert Rev Mol Med ; 15: e4, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23795910

RESUMO

Engineered tissue derived from ocular surface stem cells (SCs) are a cutting edge biotechnology for repair and restoration of severely damaged eyes as a result of ocular surface dysfunction because of SC failure. Ex-vivo SC expansion techniques have advanced significantly since the first patients were treated in the late 1990s. The techniques and clinical reports reviewed here highlight the evolution and successes of these techniques, while also revealing gaps in our understanding of ocular surface and SC biology that drives further research and development in this field. Although hurdles still remain before stem-cell-based therapies are more widely available for patients with devastating ocular surface disease, recent discoveries in the field of mesenchymal SCs and the potential of induced pluripotent SCs heralds a promising future for clinicians and our patients.


Assuntos
Doenças da Córnea/patologia , Doenças da Córnea/terapia , Epitélio Corneano/transplante , Transplante de Células-Tronco , Animais , Epitélio Corneano/patologia , Humanos , Células-Tronco/citologia , Engenharia Tecidual
11.
Surv Ophthalmol ; 68(5): 940-956, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37146692

RESUMO

Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.


Assuntos
Aniridia , Doenças da Córnea , Humanos , Doenças da Córnea/etiologia , Doenças da Córnea/terapia , Aniridia/complicações , Aniridia/terapia , Aniridia/genética , Córnea/patologia , Transtornos da Visão , Previsões
12.
Am J Pathol ; 178(1): 187-97, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21224056

RESUMO

Ocular mucous membrane pemphigoid is an immunobullous disease in which excessive conjunctival fibrosis causes blindness, and the pathogenesis of scarring is incompletely understood. To establish whether profibrotic fibroblasts with an altered phenotype exist in ocular mucous membrane pemphigoid, we compared the functional characteristics of pemphigoid conjunctival fibroblasts to normal conjunctival fibroblasts with respect to cell division; migration; collagen contraction; matrix metalloproteinase, secretion of collagen and chemokines; and myofibroblast differentiation. We found that pemphigoid fibroblasts showed increased cell division (P = 0.01), increased migration in serum-free medium (72 ± 18 migrated cells versus 33 ± 11, P = 0.04), increased collagen contraction in the presence of 10 ng/ml tumor necrosis factor-α, increased collagen type I secretion (P = 0.03), increased secretion of matrix metalloproteinase-3 (P = 0.03), and increased secretion of eotaxin in response to interleukin-13 (P = 0.04). Differences between pemphigoid and normal conjunctival fibroblasts with respect to collagen contraction and MMP secretion in the presence of interleukin-13 were also observed. Together, these findings indicate that pemphigoid conjunctival fibroblasts have a profibrotic phenotype that is maintained in vitro. No differences between pemphigoid fibroblasts obtained from acutely inflamed versus clinically uninflamed conjunctiva were observed. Developing effective antifibrotic therapies will require understanding of the mechanisms that both induce and maintain the profibrotic phenotype.


Assuntos
Túnica Conjuntiva/patologia , Fibroblastos/patologia , Penfigoide Mucomembranoso Benigno/patologia , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Divisão Celular , Movimento Celular , Células Cultivadas , Quimiocina CCL11/metabolismo , Colágeno Tipo I/metabolismo , Túnica Conjuntiva/efeitos dos fármacos , Túnica Conjuntiva/metabolismo , Meios de Cultura Livres de Soro , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose , Humanos , Interleucina-13/farmacologia , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Pessoa de Meia-Idade , Mucosa/patologia , Miofibroblastos/patologia , Fenótipo , Fator de Necrose Tumoral alfa/farmacologia
13.
Stem Cells ; 29(12): 1923-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21997829

RESUMO

Limbal epithelial stem cells (LESCs) are a population of stem cells responsible for maintenance and repair of the corneal surface. Injury and disease can result in a deficiency of these stem cells, the vision affecting condition called limbal stem cell deficiency (LSCD) in which the cornea becomes opaque, vascularized, and inflamed. Cultured LESC therapy was first described in 1997;29:19231932-19231932.and LESCs cultured from either patients or donors have been used to successfully treat LSCD. In this review, some of the challenges and controversies associated with cultured LESC therapy will be discussed including alternative stem cell sources.


Assuntos
Doenças da Córnea/terapia , Epitélio Corneano/citologia , Transplante de Células-Tronco , Células-Tronco/citologia , Técnicas de Cultura de Células , Doenças da Córnea/patologia , Epitélio Corneano/transplante , Humanos , Limbo da Córnea/lesões , Limbo da Córnea/patologia
14.
Curr Eye Res ; 47(8): 1106-1115, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35577415

RESUMO

PURPOSE: To investigate if human oral mucosal fibroblasts (HOMF) from patients with limbal stem cell deficiency (LSCD) can be used as an autologous feeder layer to support the culture of epithelial cells for potential clinical use. METHODS: HOMF were isolated from oral mucosal biopsies obtained from the following groups of patients with LSCD: aniridia, mucous membrane pemphigoid (MMP), Stevens-Johnson syndrome (SJS), and ectodermal dysplasia (ED). The ability of these cells to support the culture of human limbal epithelial cells (HLE) was compared to that of HOMF from non-LSCD donors and 3T3s commonly used to culture epithelial cells for use in the clinic to treat LSCD. RESULTS: HOMF were successfully obtained by explant culture for 3/3 aniridia patients, 3/3 MMP patients, 1/3 SJS patients, and 1/1 ED patients. All HOMF cultured from these LSCD groups supported the expansion of HLE with epithelial culture times and total colony forming efficiency (CFE) comparable to those achieved on HOMF isolated from donors without LSCD. PCR showed that all HLE cultured on LSCD donor HOMF expressed p63α, CK15, PAX6, CK12, and MUC16 as did HLE cultured on the control non-LSCD donor HOMF and 3T3s. Western blotting detected CK15 and MUC16 protein expression in all groups. CONCLUSIONS: HOMF from patients with LSCD can be successfully used to support the expansion of epithelial cells. These cells may therefore be useful as autologous feeder fibroblasts for the expansion of epithelial cells for use in the clinic to treat LSCD.


Assuntos
Aniridia , Doenças da Córnea , Epitélio Corneano , Limbo da Córnea , Aniridia/metabolismo , Células Cultivadas , Doenças da Córnea/metabolismo , Doenças da Córnea/cirurgia , Células Epiteliais/metabolismo , Células Alimentadoras , Fibroblastos , Humanos , Células-Tronco
15.
Sci Rep ; 12(1): 11432, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794158

RESUMO

Our previous study demonstrated hsa-miR-143-3p as one of the highly expressed miRNAs in enriched corneal epithelial stem cells (CESCs). Hence this study aims to elucidate the regulatory role of hsa-miR-143-3p in the maintenance of stemness in CESCs. The target genes of hsa-miR-143-3p were predicted and subjected to pathway analysis to select the targets for functional studies. Primary cultured limbal epithelial cells were transfected with hsa-miR-143-3p mimic, inhibitor or scrambled sequence using Lipofectamine 3000. The transfected cells were analysed for (i) colony forming potential, (ii) expression of stem cell (SC) markers/ transcription factors (ABCG2, NANOG, OCT4, KLF4, ΔNp63), (iii) differentiation marker (Cx43), (iv) predicted five targets of hsa-miR-143-3p (DVL3, MAPK1, MAPK14, KRAS and KAT6A), (v) MAPK signaling regulators and (vi) Wnt-ß-catenin signaling regulators by qPCR, immunofluorescence staining and/or Western blotting. High expression of hsa-miR-143-3p increased the colony forming potential (10.04 ± 1.35%, p < 0.001) with the ability to form holoclone-like colonies in comparison to control (3.33 ± 0.71%). The mimic treated cells had increased expression of SC markers but reduced expression of Cx43 and hsa-miR-143-3p targets involved in Wnt-ß-catenin and MAPK signaling pathways. The expression of ß-catenin, active ß-catenin and ERK2 in hsa-miR-143-3p inhibitor transfected cells were higher than the control cells and the localized nuclear expression indicated the activation of Wnt and MAPK signaling. Thus, the probable association of hsa-miR-143-3p in the maintenance of CESCs through inhibition of Wnt and MAPK signaling pathways was thus indicated.


Assuntos
Epitélio Corneano , Sistema de Sinalização das MAP Quinases , MicroRNAs , Células-Tronco , Via de Sinalização Wnt , beta Catenina , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Epitélio Corneano/citologia , Epitélio Corneano/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
16.
Br Med Bull ; 100: 209-25, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21926089

RESUMO

INTRODUCTION OR BACKGROUND: Corneal opacity is a common cause of blindness. The majority of cases result from ulceration and scarring following infection or trauma, but in a proportion corneal epithelial stem cell (SC) deficiency leads to an inability to maintain a healthy corneal surface. SOURCES OF DATA: This review includes systematic reviews and individual case series of treatments for corneal epithelial SC deficiency. AREAS OF AGREEMENT: Two techniques such as transplantation of large segments of cornea from a healthy eye and ex vivo expansion of corneal SCs in the laboratory were compared. Both have merits and their clinical outcomes are similar. The smaller biopsy in the cell expansion approach has less risk for the donor eye, which is a significant advantage. AREAS OF CONTROVERSY: Treatment algorithms for different aetiologies of SC failure are evolving. The proportion of true corneal epithelial SCs in ex vivo culture is unclear and it is unknown whether these cells survive long term. GROWING POINTS: In this study, the optimum method of cell culture and transplantation is being intensively investigated. AREAS TIMELY FOR DEVELOPING RESEARCH: Development of tissues using multiple cell types, genetic modification to treat hereditary corneal disorders and development of cell therapy for other eye diseases are future possibilities.


Assuntos
Doenças da Córnea/terapia , Transplante de Córnea/métodos , Transplante de Células-Tronco/métodos , Cegueira/etiologia , Doenças da Córnea/complicações , Epitélio Corneano/transplante , Humanos , Limbo da Córnea/citologia , Mucosa Bucal/transplante
17.
Regen Med ; 16(9): 871-891, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34380324

RESUMO

Corneal endothelial cells (CECs) facilitate the function of maintaining the transparency of the cornea. Damage or dysfunction of CECs can lead to blindness, and the primary treatment is corneal transplantation. However, the shortage of cornea donors is a significant problem worldwide. Thus, cultured CEC therapy has been proposed and found to be a promising approach to overcome the lack of tissue supply. Unfortunately, CECs in humans rarely proliferate in vivo and, therefore, can be extremely challenging to culture in vitro. Several promising cell isolation and culture techniques have been proposed. Multiple factors affecting the success of cell expansion including donor characteristics, preservation and isolation methods, plating density, media preparation, transdifferentiation and biomarkers have been evaluated. However, there is no consensus on standard technique for CEC culture. This review aimed to determine the challenges and investigate potential options that would facilitate the standardization of CEC culture for research and therapeutic application.


Assuntos
Transplante de Córnea , Endotélio Corneano , Células Cultivadas , Córnea , Meios de Cultura , Células Endoteliais , Humanos
18.
Am J Pathol ; 175(6): 2406-15, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19910508

RESUMO

Interleukin-13 (IL-13) is the dominant effector cytokine of fibrosis in pulmonary and liver disease. Excessive conjunctival fibrosis in the immunobullous disease ocular mucous membrane pemphigoid (MMP) causes blindness; the pathogenesis of scarring in this disease is incompletely understood. To determine whether IL-13 is involved in conjunctival fibrosis in MMP, we studied the expression of IL-13 in ocular MMP patients before and after systemic immunosuppression and examined the effects of IL-13 on normal human conjunctival fibroblasts. We found high stromal cell expression of IL-13 in active ocular MMP by immunohistochemistry; 80% of these cells were CD3-positive T cells. Following immunosuppression, in clinically uninflamed, treated, ocular MMP patients, the number of IL-13 positive cells was significantly reduced, but this was still fourfold greater than in normal conjunctiva. IL-13 stimulated collagen lattice contraction and migration, and decreased production of mmp-3 and mmp-10 by human conjunctival fibroblasts. The addition of T cell culture supernatant to IL-13 synergistically augmented fibroblast migration. IL-13 also up-regulated surface expression of HLA-DR, CD80, CD40, and CD154 by conjunctival fibroblasts, suggesting a potential mechanism for fibroblast-T cell cross talk, via which fibroblasts may actively engage in perpetuating chronic inflammation and continued fibrosis. Together, these findings suggest that IL-13 is involved in conjunctival fibrosis in MMP, and that IL-13 has both profibrotic and pro-inflammatory effects on human conjunctival fibroblasts.


Assuntos
Túnica Conjuntiva/metabolismo , Fibroblastos/metabolismo , Interleucina-13/biossíntese , Penfigoide Mucomembranoso Benigno/metabolismo , Idoso , Idoso de 80 Anos ou mais , Ensaios de Migração Celular , Separação Celular , Células Cultivadas , Colágeno/metabolismo , Túnica Conjuntiva/imunologia , Túnica Conjuntiva/patologia , Feminino , Fibroblastos/imunologia , Fibroblastos/patologia , Citometria de Fluxo , Imunofluorescência , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Interleucina-13/imunologia , Masculino , Metaloproteinases da Matriz/imunologia , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Penfigoide Mucomembranoso Benigno/imunologia , Penfigoide Mucomembranoso Benigno/patologia , Linfócitos T/imunologia
19.
Ocul Surf ; 8(2): 80-90, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20427011

RESUMO

The term ex vivo cultured limbal epithelial transplantation (CLET) refers to the process of culturing a sheet of human limbal epithelium in the laboratory and transplanting this sheet back onto the limbal stem cell-deficient cornea of the same patient or another recipient. This emerging technology represents one of the earliest successes in regenerative medicine. CLET is, at present, best suited to patients who have unilateral total limbal stem cell deficiency arising from chemical injury and who are suitable for autologous cell culture and transplantation. Although the results of allogeneic cell transplantation are encouraging and superior to conventional stem cell transplantation techniques, insufficient follow-up precludes conclusions regarding the long-term outcomes. Other tissues, such as oral mucosal epithelium, are emerging as viable alternative sources of cells, especially for patients with bilateral disease.


Assuntos
Doenças da Córnea/cirurgia , Epitélio Corneano/transplante , Limbo da Córnea/citologia , Transplante de Células/métodos , Células Cultivadas , Células Epiteliais/transplante , Humanos , Células-Tronco , Transplante Autólogo
20.
Stem Cells Dev ; 29(7): 425-439, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31973649

RESUMO

The objective of this study was to determine whether corneal stromal cells (CSCs) from the limbal and central corneal stroma in dogs have multipotent mesenchymal stem/stromal cell (MSC) properties, and whether this cell population can be differentiated into keratocyte-like cells (KDCs). Normal, donated, mesocephalic dog corneas were used to isolate CSC in vitro. Immunohistochemistry demonstrated a distinct population of CD90 expressing cells in the anterior stroma throughout the limbal and central cornea. CSC could be cultured from both the limbal and central cornea and the culture kinetics showed a progenitor cell profile. The CSC expressed stem cell markers CD90, CD73, CD105, N-cadherin, and Pax6, while CD34 was negative. Limbal and central CSC differentiated into osteoblasts, chondrocytes, and adipocytes confirming their multipotency. Coculturing allogeneic peripheral blood mononuclear cells (PBMCs) with limbal CSCs did not affect baseline PBMC proliferation indicating a degree of innate immune privilege. Limbal CSC could be differentiated into KDCs that expressed Keratocan, Lumican, and ALDH1A3 and downregulated Pax6 and N-cadherin. In conclusion, canine CSCs have multipotent MSC properties similarly described in humans and could serve as a source of cells for cell therapy and studying corneal diseases.


Assuntos
Córnea/citologia , Células-Tronco Mesenquimais/citologia , Células Estromais/citologia , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Córnea/metabolismo , Cães , Feminino , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Células Estromais/metabolismo
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