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1.
BMC Ophthalmol ; 24(1): 409, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300402

RESUMEN

BACKGROUND: Human amniotic membrane (AM) transplantation has been applied to treat ocular surface diseases, including corneal trauma. The focus of much deliberation is to balance the mechanical strength of the amniotic membrane, its resistance to biodegradation, and its therapeutic efficacy. It is commonly observed that the crosslinked human decellularized amniotic membranes lose the functional human amniotic epithelial cells (hAECs), which play a key role in curing the injured tissues. METHODS AND RESULTS: In this study, we crosslinked human decellularized amniotic membranes (dAM) with genipin and re-planted the hAECs onto the genipin crosslinked AM. The properties of the AM were evaluated based on optical clarity, biodegradation, cytotoxicity, and ultrastructure. The crosslinked AM maintained its transparency. The color of crosslinked AM deepened with increasing concentrations of genipin. And the extracts from low concentrations of genipin crosslinked AM had no toxic effect on human corneal epithelial cells (HCECs), while high concentrations of genipin exhibited cytotoxicity. The microscopic observation and H&E staining revealed that 2 mg/mL genipin-crosslinked dAM (2 mg/mL cl-dAM) was more favorable for the attachment, migration, and proliferation of hAECs. Moreover, the results of the CCK-8 assay and the transwell assay further indicated that the living hAECs' tissue-engineered amniotic membranes could facilitate the proliferation and migration of human corneal stromal cells (HCSCs) in vitro. CONCLUSIONS: In conclusion, the cl-dAM with living hAECs demonstrates superior biostability and holds significant promise as a material for ocular surface tissue repair in clinical applications.


Asunto(s)
Amnios , Proliferación Celular , Epitelio Corneal , Ingeniería de Tejidos , Humanos , Ingeniería de Tejidos/métodos , Epitelio Corneal/citología , Células Cultivadas , Enfermedades de la Córnea/cirugía , Iridoides/farmacología , Células Epiteliales
2.
Arch Med Sci ; 20(3): 813-821, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39050175

RESUMEN

Introduction: Oral epithelial cells were recently shown to be able to differentiate into corneal epithelium, and the efficacy of cultured autologous oral mucosal epithelial cells (CAOMEC) has been suggested by the presence of epithelium replacement. Therefore, the aim of this study was to evaluate the treatment outcome in limbal stem cell deficiency (LSCD) by adding CAOMEC to regular amniotic membrane (AM) treatment. Material and methods: Eyes with LSCD were randomized to two groups to undergo either autologous oral mucosal epithelial cell sheet (CAOMECS) combined with AM transplantation (A group) or AM transplantation alone (B group). Clinical outcome measures were corneal epithelium healing, best corrected visual acuity, symblepharon, corneal transparency, corneal neovascularization and ocular surface inflammation. Results: The normal corneal epithelialization rate in group A (73.33%) was higher than that in group B (35.48%), and the average healing time was shorter (3.45 ±2.12 weeks vs. 4.64 ±1.63 weeks). The symblepharon in the above two groups was improved in the first 3 months after surgery, but after 6 months, part of the B group had recurrence. In improving corneal transparency, group A has obvious advantages. Corneal neovascularization (CNV) was improved to some extent in the first 3 months after surgery, but group A (1.47 ±0.64) was better than group B (1.94 ±0.85) after 6 months. Both groups can improve the inflammatory state to some extent. Conclusions: The transplantation of CAOMECS offers a viable and safe alternative in the reconstruction of a stable ocular surface. The effect is better than that of traditional AM transplantation, mainly in promoting corneal epithelialization, improving ocular surface structure, and reducing fiber and vascular infiltration.

3.
Diagnostics (Basel) ; 13(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36673009

RESUMEN

BACKGROUND: Limbal stem cell deficiency (LCSD) presents several challenges. Currently, there is no clearly defined systematic approach to LSCD diagnosis that may guide surgical tactics. METHODS: The medical records of 34 patients with LSCD were analyzed. Diagnostic modalities included standard (visometry, tonometry, visual field testing, slit-lamp biomicroscopy with corneal fluorescein staining, Schirmer test 1, ultrasonography) and advanced ophthalmic examination methods such as anterior segment optical coherence tomography, in vivo confocal microscopy, impression cytology, and enzyme-linked immunoassay. RESULTS: Standard ophthalmological examination was sufficient to establish the diagnosis of LSCD in 20 (58.8%) cases, whereas advanced evaluation was needed in 14 (41.2%) cases. Depending on the results, patients with unilateral LSCD were scheduled to undergo glueless simple limbal epithelial transplantation (G-SLET) or simultaneous G-SLET and lamellar keratoplasty. Patients with bilateral LSCD with normal or increased corneal thickness were enrolled in the paralimbal oral mucosa epithelium transplantation (pLOMET) clinical trial. CONCLUSIONS: Based on the diagnostic and surgical data analyzed, the key points in LSCD diagnosis were identified, helping to guide the surgeon in selecting the appropriate surgical procedure. Finally, we proposed a novel step-by-step diagnostic algorithm and original surgical guidelines for the treatment of patients with LSCD.

4.
Exp Eye Res ; 227: 109356, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36563893

RESUMEN

The most commonly used tissue substitute for ocular surface reconstruction is human amniotic membrane (AM). Because of its low biomechanical strength and intransparency there is a need to search for alternatives of consistent quality. This study, further explored the biocompatibility of Keratin Film (KF) and its ability to sustain corneal epithelial wound healing. In three equal groups of 5 New Zeeland white rabbits a 4 mm superficial keratectomy was created in the right eye. Five eyes received a KF, five a human AM graft and the remaining five no implant. All eyes were treated with ofloxacin and dexamethasone eye drops and followed up for 10 days. Corneal fluorescein staining, vascularization, and transparency were assessed using slit lamp biomicroscopy according to a standardized grading score during and at the end of follow-up. The corneal-scleral-button was excised and processed for histology. After 10 days all eyes which had received a KF showed complete epithelial healing and no signs of neovascularization. In the AM group 1 eye showed a persistent epithelial defect at day 10 and 2 eyes showed neovascularization at day 7 resolving at day 10. Transparency improved progressively both in the KF group as well as in the AM group towards the end of the follow. Histology showed a multilayer epithelium firmly adherent to the KF with no evidence of keratocyte migration or inflammatory reaction in the corneal stroma. In this study on rabbit eyes KF better supported corneal epithelial wound healing than amniotic membrane.


Asunto(s)
Córnea , Epitelio Corneal , Queratinas , Cicatrización de Heridas , Animales , Humanos , Conejos , Córnea/cirugía , Sustancia Propia , Epitelio , Epitelio Corneal/fisiopatología , Queratinas/administración & dosificación , Cicatrización de Heridas/fisiología
5.
Acta Biomater ; 153: 273-286, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36162761

RESUMEN

The conjunctiva covers the largest area of ocular surface and is responsible for tear balance and clear vision. After trauma or surgery, the conjunctiva is prone to scarring and contracture. Transplantation with suture often implies numerous complications, such as inflammation, suture erosion, granuloma. And the suture needs to be removed, which means a secondary trauma. In this study, a bioadhesive hydrogel (GMO) for sutureless conjunctival transplantation was developed based on a semi-interpenetrating polymer network (sIPN) consisting of gelatin methacrylate (GelMA) and oxidized hyaluronic acid (OHA). The maximum adhesion strength was 157 ± 17 kPa, and the burst pressure was 357 ± 29 kPa, which was 15 times higher than the human intraocular pressure (IOP). GMO bioadhesive hydrogel significantly improved surgical efficiency and secured the collagen scaffold firmly to a rabbit conjunctival defect. The sutureless transplantation approach revealed the promoted tissue repair without scar. In conclusion, GMO bioadhesive may be an attractive alternative to suture for ocular surface reconstruction by avoiding suture-related complications and improving clinical outcome. STATEMENT OF SIGNIFICANCE: Conjunctival tissue is prone to scarring and contracture after trauma, and surgery with sutures often implies numerous complications. In this study, the ocular surface reconstruction was achieved by sutureless transplantation of conjunctival scaffold using bioadhesive hydrogel. The prepared GMO bioadhesive based on the semi-interpenetrating network of gelatin methacrylate (GelMA) and oxidized hyaluronic acid (OHA) had favorable adhesion and mechanical properties. The sutureless transplantation approach significantly improved the operation efficiency, avoided suture-related complications, and promoted the regeneration of conjunctiva. This study highlights the great potential of the sutureless repair strategy for clinical application in ocular surface reconstruction.


Asunto(s)
Contractura , Gelatina , Animales , Humanos , Conejos , Ácido Hialurónico/farmacología , Polímeros , Cicatriz , Conjuntiva/cirugía , Hidrogeles/farmacología , Metacrilatos
6.
Cell Tissue Bank ; 23(4): 851-861, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35338396

RESUMEN

PURPOSE: To compare the effects on adhesive and structural properties of newer preservation conditions to those obtained with an established, standardized protocol (dimethyl sulfoxide at -180 °C). In attempt to simplify and enhance the safety of the procedure, we tested dextran-based freezing medium and a dry condition (no medium) at temperatures of -80 °C. METHODS: Five patches of human amniotic membrane were obtained from three different donors. For each donor, five preservation condition were tested: dimethyl sulfoxide at -180 °C, dimethyl sulfoxide at -80 °C, dextran-based medium at -180 °C, dextran-based medium at -80 °C and dry freezing at -80 °C (no medium). At the end of four months storage period, adhesive properties and structure were analyzed. RESULTS: None of the newer preservation protocols showed differences in adhesive and structural properties of the tissues. The stromal layer always kept its adhesiveness, while both structure and basement membrane were not altered by any the preservation protocol. CONCLUSIONS: Switching from liquid nitrogen cryopreservation to -80 °C would reduce manipulation, simplify the procedure, making it also cheaper. The use of dextran-based freezing medium or no medium at all (dry condition) would avoid the potential toxicity of the dimethyl sulfoxide-based freezing media.


Asunto(s)
Crioprotectores , Dimetilsulfóxido , Humanos , Crioprotectores/farmacología , Amnios , Dextranos , Criopreservación/métodos
7.
Exp Eye Res ; 216: 108931, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35063476

RESUMEN

The purpose of the study was to establish a simple ex vivo corneal re-epithelization model and study the labial mucosal epithelium grafting as a potential approach for ocular surface reconstruction. Four human donor corneal buttons were overstored in a corneal cold storage solution at 4 °C for 32-52 days. Four labial oral mucosa strips were dissected from four patients during fornix reconstruction after they signed informed consent. The substantia propria was trimmed off, and the resulting graft was sutured near the corneal limbus with running sutures (thus forming the tissue construct). Constructs were cultured under the standard conditions with the anterior corneal side outwards. After 3 weeks of culture, constructs were removed, washed, and fixed. Sections were stained with hematoxylin and eosin (HE), anti-keratins 4, 13, 19, and p63. Nuclei were counterstained with Hoechst. After the cultivation, all constructs were integral with the attached graft and non-loosened sutures. The native cells were absent in all donor corneas. Histological evaluation demonstrated that the labial mucosal grafts were attached to the Bowman's membrane (BM), and its cellular outgrowths were found to be transit from the graft to the BM over the anterior surface in all constructs. Cells expressed mucosal epithelial keratins 4, 13, and 19, and several were p63-positive in nuclei. In the study, a simple ex vivo corneal re-epithelization model was successfully established. The model was potent in studying the labial mucosal epithelium grafting as an option for autologous ocular surface reconstruction in patients with bilateral limbal stem cell deficiency.


Asunto(s)
Células Epiteliales/trasplante , Epitelio Corneal/fisiología , Limbo de la Córnea/cirugía , Mucosa Bucal/citología , Repitelización/fisiología , Adulto , Anciano , Células Cultivadas , Enfermedades de la Córnea/fisiopatología , Enfermedades de la Córnea/cirugía , Humanos , Queratinas/metabolismo , Persona de Mediana Edad , Modelos Biológicos , Trasplante de Células Madre , Células Madre/patología , Técnicas de Sutura
8.
Middle East Afr J Ophthalmol ; 29(4): 232-234, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38162568

RESUMEN

Limbal stem cell deficiency (LSCD) is a very challenging situation and difficult to manage. A great works and ideas were conducted over the past 50 years. Numerous surgical techniques were proposed. We are reporting more than a 20-year follow-up of a case of limbal autograft stem cell transplantation due to LSCD secondary to chemical injury.


Asunto(s)
Enfermedades de la Córnea , Epitelio Corneal , Limbo de la Córnea , Humanos , Enfermedades de la Córnea/cirugía , Autoinjertos , Estudios de Seguimiento , Limbo de la Córnea/cirugía , Agudeza Visual , Amnios/trasplante , Trasplante de Células Madre/métodos , Epitelio Corneal/trasplante
9.
J Biomed Mater Res B Appl Biomater ; 109(10): 1488-1504, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33538123

RESUMEN

The in vitro reconstruction of stromal tissue by long-term cultivation of corneal fibroblasts is a smart approach for regenerative therapies of ocular surface diseases. However, systematic investigations evaluating optimized cultivation protocols for the realization of a biomaterial are lacking. This study investigated the influence of supplements to the culture media of human corneal fibroblasts on the formation of a cell sheet consisting of cells and extracellular matrix. Among the supplements studied are vitamin C, fetal bovine serum, L-glutamine, components of collagen such as L-proline, L-4-hydroxyproline and glycine, and TGF-ß1, bFGF, IGF-2, PDGF-BB and insulin. After long-term cultivation, the proliferation, collagen and glycosaminoglycan content and light transmission of the cell sheets were examined. Biomechanical properties were investigated by tensile tests and the ultrastructure was characterized by electron microscopy, small-angle X-ray scattering, antibody staining and ELISA. The synthesis of extracellular matrix was significantly increased by cultivation with insulin or TGF-ß1, each with vitamin C. The sheets exhibited a high transparency and suitable material properties. The production of a transparent, scaffold-free, potentially autologous, in vitro-generated construct by culturing fibroblasts with extracellular matrix synthesis-stimulating supplements represents a promising approach for a biomaterial that can be used for ocular surface reconstruction in slowly progressing diseases.


Asunto(s)
Materiales Biocompatibles/química , Sustancia Propia/metabolismo , Matriz Extracelular/metabolismo , Andamios del Tejido/química , Ácido Ascórbico/metabolismo , Técnicas de Cultivo de Célula , Proliferación Celular , Medios de Cultivo/metabolismo , Fibroblastos/citología , Glutamina/metabolismo , Glicina/metabolismo , Humanos , Hidroxiprolina/metabolismo , Prolina/metabolismo , Regeneración , Albúmina Sérica Bovina/metabolismo , Propiedades de Superficie , Resistencia a la Tracción , Ingeniería de Tejidos , Factor de Crecimiento Transformador beta1/metabolismo
10.
Am J Ophthalmol Case Rep ; 20: 100982, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33195879

RESUMEN

PURPOSE: To report the surgical management of extensive epibulbar dermoids with autologous oral mucous membrane transplantation. OBSERVATIONS: While rare, extensive dermoids that encroach upon the visual axis carry a poor prognosis. We report the case of a 7-week old premature male infant who presented with large bilateral epibulbar dermoids obscuring the visual axis. He was treated first with sequential bilateral optical iridectomies under the clearest corneal areas, followed several months later by sequential dermoid excision and amniotic membrane transplantation in each eye. He subsequently underwent autologous "simple" oral mucosal epithelial transplantation (SOMET) as well as strabismus surgery. Conclusions and Importance: Here we present the first case, to the best of our knowledge, of the use of SOMET in managing post-operative pseudopterygium following dermoid excision. To our knowledge it is the also the first application of this technique in a young pediatric patient. A good clinical outcome may be achieved with SOMET, which may offer a minimally invasive alternative to other traditional modalities.

11.
Ocul Surf ; 18(4): 901-911, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32860970

RESUMEN

PURPOSE: The long-term success of visual rehabilitation in patients with severe conjunctival scarring is reliant on the reconstruction of the conjunctiva with a suitable substitute. The purpose of this study is the development and investigation of a re-epithelialized conjunctival substitute based on porcine decellularized conjunctiva (PDC). METHODS: PDC was re-epithelialized either with pre-expanded human conjunctival epithelial cells (PDC + HCEC) or with a human conjunctival explant placed directly on PDC (PDC + HCEx). Histology and immunohistochemistry were performed to evaluate epithelial thickness, proliferation (Ki67), apoptosis (Caspase 3), goblet cells (MUC5AC), and progenitor cells (CK15, ΔNp63, ABCG2). The superior construct (PDC + HCEx) was transplanted into a conjunctival defect of a rabbit (n = 6). Lissamine green staining verified the epithelialization in vivo. Orbital tissue was exenterated on day 10 and processed for histological and immunohistochemical analysis to examine the engrafted PDC + HCEx. A human-specific antibody was used to detect the transplanted cells. RESULTS: From day-14 in vitro onward, a significantly thicker epithelium and greater number of cells expressing Ki67, CK15, ΔNp63, and ABCG2 were noted for PDC + HCEx versus PDC + HCEC. MUC5AC-positive cells were found only in PDC + HCEx. The PDC + HCEx-grafted rabbit conjunctivas were lissamine-negative during the evaluation period, indicating epithelial integrity. Engrafted PDC + HCEx showed preserved progenitor cell properties and an increased number of goblet cells comparable to those of native conjunctiva. CONCLUSION: Placing and culturing a human conjunctival explant directly on PDC (PDC + HCEx) enables the generation of a stable, stratified, goblet cell-rich construct that could provide a promising alternative conjunctival substitute for patients with extensive conjunctival stem and goblet cell loss.


Asunto(s)
Conjuntiva , Animales , Células Epiteliales , Células Caliciformes , Humanos , Mucina 5AC , Conejos , Células Madre , Porcinos
12.
J Tissue Eng Regen Med ; 14(9): 1318-1332, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32652796

RESUMEN

The shortage of donor corneas as well as the limitations of tissue substitutes leads to the necessity to develop alternative materials for ocular surface reconstruction. Corneal surface substitutes must fulfill specific requirements such as high transparency, low immunogenicity, and mechanical stability combined with elasticity. This in vitro study evaluates a decellularized matrix secreted from human corneal fibroblasts (HCF) as an alternative material for ocular surface reconstruction. HCF from human donors were cultivated with the supplementation of vitamin C to form a stable and thick matrix. Furthermore, due to enhanced cultivation time, a three-dimensional like multilayered construct which partly mimics the complex structure of the corneal stroma could be generated. The formed human cell-based matrices (so-called cell sheets [CS]) were subsequently decellularized. The complete cell removal, collagen content, ultrastructure, and cell toxicity of the decellularized CS (DCS) as well as biomechanical properties were analyzed. Surgical feasibility was tested on enucleated porcine eyes. After decellularization and sterilization, a transparent, thick, cell free, and sterile tissue substitute resulted, which allowed expansion of limbal epithelial stem cells with no signs of cytotoxicity, and good surgical feasibility. DCS seem to be a promising new corneal tissue substitute derived from human cells without the limitation of donor material; however, future in vivo studies are necessary to further elucidate its potential for ocular surface reconstruction.


Asunto(s)
Sustancia Propia/fisiología , Procedimientos de Cirugía Plástica , Ingeniería de Tejidos , Animales , Fenómenos Biomecánicos , Muerte Celular , Colágeno/metabolismo , Sustancia Propia/ultraestructura , Células Epiteliales/citología , Humanos , Imagen Óptica , Reproducibilidad de los Resultados , Células Madre/citología , Porcinos , Resistencia a la Tracción
13.
Ophthalmic Res ; 63(4): 423-426, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31838481

RESUMEN

PURPOSE: A hyper-dry amniotic membrane (HDAM) has been used clinically for ocular surface reconstruction, but sufficient evidence of the histological dynamics and long-term safety have not been obtained. We examined the histological changes in an HDAM after its subconjunctival implantation in rabbit eyes, and we compared these changes to those in the Ambio2TM Amniotic Membrane Graft (IOP Ophthalmics, Costa Mesa, CA, USA) after the same surgery. DESIGN: A prospective controlled animal study. METHODS: We used 27 rabbits in two groups: the HDAM group (36 eyes of 18 rabbits) and the Ambio2 group (18 eyes of 9 rabbits). The HDAM or Ambio2 was transplanted on the bare sclera and covered with a conjunctival autograft. The histological changes were determined by evaluating the amniotic membrane graft, inflammatory cells, and foreign body granulomas in hematoxylin/eosin-stained sections at 30 days, 93 days, and 184 days postoperatively. RESULTS: In all cases, the amniotic membrane graft was completely absorbed without scarring at 184 days postoperatively. The positive rate of inflammatory cells was significantly higher in the HDAM group compared to the Ambio2 group at 30 days postoperatively. The positive rate of foreign body granulomas decreased with time, with no significant difference between the two groups. CONCLUSIONS: Both the HDAM and Ambio2 were completely absorbed without scarring within 6 months after surgery. The two types of membranes showed histologically equivalent responses. Translational Relevance: Since the HDAM was completely absorbed without scarring within 6 months after surgery, we could confirm its long-term safety.


Asunto(s)
Amnios/trasplante , Conjuntiva/cirugía , Amnios/patología , Animales , Conjuntiva/patología , Eosinófilos/patología , Supervivencia de Injerto , Estudios Prospectivos , Conejos , Trasplante Autólogo
14.
Rom J Ophthalmol ; 63(3): 273-276, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31687631

RESUMEN

Purpose. To report a case of benign fibrous histiocytoma of the conjunctiva involving the cornea, an uncommon ocular surface tumor. Methods. A 57-year-old patient came in our service complaining of a progressively enlarging conjunctival mass temporally to the limbus and invading the adjacent cornea of the left eye. Results. The approach consisted in surgical excision followed by cryotherapy on the edges and on the base of the excision site and amniotic membrane patch reconstruction of the ocular surface defect. Pathologic examination and immunohistochemistry were performed in order to establish the diagnosis. No recurrences appeared in 8 months of follow up. Conclusions. Fibrous histiocytoma might be easily misdiagnosed as it is exceedingly rare. Complete resection with careful inspection of edges is advised. Cryotherapy at the base and borders of the resection site is recommended as both benign and malignant tumors can show recurrence. Amniotic membrane should always be regarded as an efficient option in reconstruction of broad surface defects after tumor resection. Abbreviations: FH = fibrous histiocytoma, CIN = corneal intraepithelial neoplasia, SSCA = squamous cell carcinoma, AM = amniotic membrane, MMC = topical mitomycin-C, 5-FU = 5-fluorouracil, BCVA = best corrected visual acuity.


Asunto(s)
Conjuntiva/patología , Enfermedades de la Conjuntiva/diagnóstico , Crioterapia/métodos , Histiocitoma Fibroso Benigno/diagnóstico , Procedimientos Quirúrgicos Oftalmológicos/métodos , Enfermedades de la Conjuntiva/terapia , Diagnóstico Diferencial , Histiocitoma Fibroso Benigno/terapia , Humanos , Masculino , Persona de Mediana Edad , Lámpara de Hendidura
15.
Stem Cells Transl Med ; 8(7): 620-626, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30868769

RESUMEN

The conjunctiva is a clear tissue covering the white part of the eye and lines the back of the eyelids. Conjunctival diseases, such as symblepharon, cause inflammation, discharges, and photophobia. The treatment often requires excision of large parts of conjunctiva. Tissue engineering of conjunctival cells using human amniotic membrane (HAM) denuded of its epithelium as a basement membrane scaffold has been shown to be effective for covering conjunctival defects. However, most epithelial denudation protocols are time-consuming and expensive or compromise HAM's basement membrane structure and matrix components. We have previously described a method to de-epithelialize HAM using ice-cold urea (uHAM). In this report, we used this method to provide tissue-engineered constructs with cultivated conjunctival epithelial cells on uHAM in two patients, one with a giant conjunctival nevus and the other with a large symblepharon. Autologous conjunctival epithelial cells harvested from incisional biopsies of these two patients were cultured on the uHAM scaffold. The transplantation of tissue-engineered constructs to patients' ocular surface immediately after the removal of lesions showed successful reconstruction of the ocular surface. Postoperatively, there were neither recurrence of lesions nor epithelial defects throughout the follow-up (up to 7 and 19 months, respectively). This report highlights the translational potential of an efficient and inexpensive method to prepare de-epithelialized HAM as a basement membrane scaffold for cell-based tissue-engineered treatments of ocular surface disorders. Stem Cells Translational Medicine 2019;8:620&626.


Asunto(s)
Amnios/química , Conjuntiva/trasplante , Células Epiteliales/trasplante , Repitelización , Ingeniería de Tejidos , Urea/química , Adolescente , Membrana Basal/química , Membrana Basal/trasplante , Conjuntiva/citología , Células Epiteliales/citología , Femenino , Humanos , Masculino , Trasplante Autólogo
16.
Tissue Eng Part A ; 25(15-16): 1084-1095, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30501562

RESUMEN

IMPACT STATEMENT: Conjunctival integrity is crucial for a healthy ocular surface and visual acuity. In severe cases of inflammatory surface disorders or after trauma, thermal or chemical burns as well as after ocular surgery, a surgical reconstruction using conjunctival substitutes is required. Due to limitations of currently used substitutes, such as the amniotic membrane, there is a need for the development of new scaffolds of consistent quality for conjunctival reconstruction. This study explored the biocompatibility and surgical usability of plastic-compressed collagen as an alternative conjunctival substitute in a rabbit model.


Asunto(s)
Colágeno/farmacología , Conjuntiva/patología , Plásticos/química , Cicatrización de Heridas/efectos de los fármacos , Amnios/trasplante , Animales , Modelos Animales de Enfermedad , Epitelio/efectos de los fármacos , Humanos , Miofibroblastos/efectos de los fármacos , Conejos , Ratas
17.
Int Med Case Rep J ; 11: 161-165, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30100765

RESUMEN

PURPOSE: Nevi of the conjunctiva are usually benign pigmented tumorous lesions located in the bulbar conjunctiva. In most conjunctival nevus cases, the patient wants the lesion to be removed for cosmetic reasons, but excisional biopsies are best for lesions suspicious for malignancy. This case report illustrates the intraoperative surgical management, histological findings, and the course of healing in a conjunctival nevus patient. CASE REPORT: A 26-year-old man was referred to our eye hospital with a large bulbar conjunctival nevus of the right eye. Upon examination, there was a large pigmented lesion with numerous small cysts present on the superior bulbar conjunctiva. The conjunctival tumor was resected, and an amniotic membrane transplantation was performed for the bulbar conjunctival reconstruction. The histopathological diagnosis suggested a conjunctival nevus. After the resection, a reduction in the inflammation and healing of the conjunctival lesion could be seen. The epithelialization of the bulbar conjunctiva over the amniotic membrane was complete 4 weeks after the resection. At the 6-month follow-up, there was no sign of recurrence or any postoperative complications. CONCLUSION: A surgical excision combined with reconstruction via amniotic membrane transplantation is effective and economical for the treatment of large conjunctival lesions.

18.
J Tissue Eng Regen Med ; 11(3): 896-904, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-25676608

RESUMEN

Ocular surface disorders, such as pterygium, cicatricial pemphigoid and external disruptions, can cause severe inflammation, scarring, fornix shortening as well as ankyloblepharon. Current treatments do not resolve these conditions sufficiently. The aim of this study was to evaluate clinical applicability and suitability of plastic compressed collagen to serve as a substrate for the expansion of human conjunctival epithelial cells in order to develop an epithelialized conjunctival substitute for fornix reconstruction. Human conjunctival epithelial cells were expanded on plastic compressed collagen gels. Epithelial cell characteristics were evaluated by haematoxylin and eosin staining, electron microscopy and cytokeratin expression. The expression of putative epithelial progenitor cell markers p63α, ABCG2 and CK15 was assessed by immunostaining. The proliferative capacity and clonal growth of the cells was evaluated before (P0) and after expansion (P1) on the plastic compressed collagen gels by colony forming efficiency assay. The potential clinical applicability of this gel substitutes was evaluated by assessment of their biomechanical properties as well as their surgical handling. Human conjunctival epithelial cells cultured on plastic and plastic compressed collagen gels formed a confluent cell layer and expressed CK19. The cells showed expression of the putative epithelial progenitor cell markers p63α, ABCG2 and CK15 and sustained colony forming ability. The compressed collagen gels showed a high ultimate tensile strength and elasticity and the surgical handling of gels was comparable to amniotic membrane. An epithelialized conjunctival tissue construct on the basis of compressed collagen might therefore be a promising alternative bioartificial tissue substitute for conjunctival reconstruction. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Colágeno/farmacología , Conjuntiva/fisiología , Plásticos/farmacología , Células 3T3 , Animales , Fenómenos Biomecánicos , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/ultraestructura , Humanos , Inmunohistoquímica , Ratones , Conejos , Ratas , Resistencia a la Tracción
19.
Int Ophthalmol ; 37(1): 71-78, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27061904

RESUMEN

The aim of the study is to evaluate the long-term clinical results of amniotic membrane transplantation (AMT) combined with mitomycin C (MMC) for reconstruction of conjunctival defects created during the excision of ocular surface squamous neoplasia (OSSN). Eight consecutive eyes of seven patients (five males and two females; mean age, 64 ± 19 years) treated by one surgeon (KH) were included in this study. AMT was performed after excision of a mass region, along with 0.04 % MMC treatment for the exposed sclera. The tumor size, histopathological retrieval, AM graft size after tumor excision, recurrence, and postoperative complications were recorded. During a mean postoperative follow-up period of 60.9 ± 14.6 months (range 36-78 months), the ocular surfaces completely re-epithelialized in all cases. The median size of the tumor was 44.4 ± 21.2 mm2 (range 13-67 mm2). The histopathological diagnoses were five cases of squamous cell carcinoma in situ (SCC in situ) and three cases of dysplasia. The median size of the AM graft after tumor excision was 100.8 ± 32.7 mm2 (range 49-151 mm2). A case of recurrent SCC in situ with a preoperative history of using MMC eye drops developed further corneal limbal deficiency and was treated with therapeutic soft contact lenses. A case of dysplasia with a history of large pterygial excision developed symblepharon postoperatively was treated with AMT 6 months after tumor excision. The tumors recurred in two eyes with SCC in situ and were successfully treated with continuous AMT and MMC. No severe complications, such as infections, corneal or scleral thinning, or ulceration developed in all cases. The combination of AMT and MMC is effective for safe reconstruction over the long-term after the excision of OSSN with postoperative careful observation and treatment. In recurrent tumor excision cases, AMT is a suitable technique for repeated ocular surface reconstruction.


Asunto(s)
Amnios/trasplante , Antibióticos Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/cirugía , Neoplasias de la Conjuntiva/cirugía , Mitomicina/uso terapéutico , Procedimientos Quirúrgicos Oftalmológicos/métodos , Procedimientos de Cirugía Plástica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Terapia Combinada , Conjuntiva/cirugía , Neoplasias de la Conjuntiva/patología , Femenino , Humanos , Limbo de la Córnea/patología , Masculino , Persona de Mediana Edad
20.
Ocul Surf ; 14(2): 168-88, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-26882981

RESUMEN

Our purpose is to comprehensively review the state of the art with regard to Stevens- Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), with particular attention to improving the management of associated ocular surface complications. SJS and TEN are two ends of a spectrum of immune-mediated disease, characterized in the acute phase by a febrile illness followed by skin and mucous membrane necrosis and detachment. Part I of this review focused on the systemic aspects of SJS/TEN and was published in the January 2016 issue of this journal. The purpose of Part II is to summarize the ocular manifestations and their management through all phases of SJS/TEN, from acute to chronic. We hope this effort will assist ophthalmologists in their management of SJS/TEN, so that patients with this complex and debilitating disease receive the best possible care and experience the most optimal outcomes in their vision and quality of life.


Asunto(s)
Síndrome de Stevens-Johnson , Epidermis , Oftalmopatías , Humanos , Necrosis , Calidad de Vida , Piel
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