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2.
Ocul Surf ; 32: 71-80, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38224776

RESUMO

This study compared the long-term outcome of different epithelial transplantation techniques to treat limbal stem cell deficiency (LSCD). We conducted a retrospective 15-year comparative systematic cohort study of patients with LSCD who underwent either cultivated limbal epithelial transplantation (CLET), simple limbal epithelial transplantation (SLET), or cultivated oral mucosal epithelial transplantation (COMET). We reviewed the demographic data, etiology, LSCD severity, best-corrected visual acuity, surgical outcomes, and complications. A total of 103 eyes of 94 patients (mean age, 45.0 ± 16.4 years) with LSCD were enrolled. The most common cause of LSCD was chemical injury (42.7 %). The median follow-up time was 75 months. The success rates of CLET, SLET, and COMET were 45.5 %, 77.8 %, and 57.8 %, respectively. The 7-year survival rates after CLET, SLET, and COMET were 50.0 %, 72.2 %, and 53.2 %, respectively. Steven-Johnson syndrome (SJS) had a significantly lower survival rate than other causes (p < 0.001), but SLET had a significantly higher survival rate than CLET (p = 0.018) and COMET (p = 0.047). Visual improvement of more than four Snellen lines was achieved in 53.1 % of successful cases and 28.2 % of failed cases. SJS, Schirmer I test <5 mm, and the presence of postoperative recurrent epithelial defects were significant risk factors for a failed surgery. All epithelial transplantation techniques had favorable long-term surgical outcomes. More than half of the patients achieved a stable ocular surface and visual acuity improvement up to 7 years postoperatively. SLET tends to have a better surgical outcome than CLET and COMET, especially in patients with SJS.


Assuntos
Doenças da Córnea , Epitélio Corneano , Limbo da Córnea , Transplante de Células-Tronco , Acuidade Visual , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Limbo da Córnea/citologia , Limbo da Córnea/cirurgia , Masculino , Feminino , Doenças da Córnea/cirurgia , Adulto , Transplante de Células-Tronco/métodos , Epitélio Corneano/transplante , Epitélio Corneano/patologia , Seguimentos , Células-Tronco , Resultado do Tratamento , Idoso , Adulto Jovem , Fatores de Tempo , Células Epiteliais/transplante , Adolescente , Deficiência Límbica de Células-Tronco
3.
Sci Rep ; 13(1): 4290, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922551

RESUMO

This non-comparative cohort study investigated long-term donor cell survival after allogenic simple/cultivated limbal epithelial transplantations (allo-SLET/allo-CLET, respectively) by genetic analysis. Transplanted corneal epithelial cells, which underwent impression cytology and/or corneal-button biopsy, were examined for personal identities of autosomal short-tandem repeats; the percentages of donor cells were calculated based on matching recipient or donor buccal-DNA references. Twelve patients were included; 4 underwent allo-CLET, 8 underwent allo-SLET. Eight patients (67%) had total limbal stem cell deficiency (LSCD). Genetic analysis was performed postoperatively (mean, 55.3 months). Donor cells were detected in 4 of 12 patients (25%), all of whom underwent allo-SLET; 1 patient had a donor genotype and 3 patients had a mixed donor/recipient genotype. The longest time of donor cell detection was 30 months. Seven patients (58%) used systemic immunosuppressives at the time of genetic analysis (mean use, 22.5 months). Allogenic donor cells survived in both procedures for the long term postoperatively, which encourages the long-term use of systemic immunosuppressives. Donor cells may not be the only factor in graft survival, in that most successful cases had a recipient profile. Their presence for a specific time may promote niches for the patients' own cells to repopulate, especially for partial LSCD.


Assuntos
Doenças da Córnea , Epitélio Corneano , Deficiência Límbica de Células-Tronco , Limbo da Córnea , Humanos , Transplante de Células-Tronco/métodos , Estudos de Coortes , Transplante Autólogo , Células Epiteliais/transplante , Doadores de Tecidos , Limbo da Córnea/patologia , Epitélio Corneano/transplante , Doenças da Córnea/patologia
4.
Cornea ; 42(9): 1116-1123, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730781

RESUMO

PURPOSE: The purpose of this study was to introduce a new method of limbal stem cell transplantation using autologous platelet-rich plasma (E-PRP) eye drops for unilateral total limbal stem cell deficiency. METHODS: Patients with total unilateral limbal stem cell deficiency due to chemical burn underwent mini-conjunctival limbal autograft using autologous E-PRP drops. One small limbal block, measuring 2 × 2 mm, was harvested from the patients' contralateral healthy eye and transplanted to the diseased eye. All patients received E-PRP drops until achieving complete corneal epithelialization. Subsequent corneal transplantation was performed in eyes with significant stromal opacification. Corneal buttons obtained during corneal transplantation underwent immunohistochemistry for the evaluation of limbal stem cell markers (ABCG2 and P63). Visual acuity, epithelial healing, corneal clarity, and regression of corneal conjunctivalization/vascularization were evaluated after surgery. RESULTS: Ten patients with acid (n = 7) or alkali (n = 3) burn were included. The mean follow-up period was 21.7 ± 5.8 months (range, 12-32 months). Corneas were completely reepithelialized within 14.9 ± 3.5 days (range, 11-21 days). Corneal conjunctivalization/vascularization dramatically regressed 1 to 2 months after surgery in all cases, and corneal clarity considerably improved in 7 patients. In the 3 eyes with significant stromal opacification, subsequent optical penetrating keratoplasty was performed. The ocular surface was stable throughout the follow-up period in all eyes. BSCVA improved to 0.60 ± 0.0.32 and 0.46 ± 0.0.25 logMAR in eyes with and without corneal transplantation, respectively, at the final follow-up visit. ABCG2 and P63 markers were detected on corneal buttons after keratoplasty. CONCLUSIONS: Based on our clinical and laboratory findings, mini-conjunctival limbal autograft using E-PRP can be considered as a promising alternative to ocular surface reconstruction.


Assuntos
Queimaduras Químicas , Doenças da Córnea , Neovascularização da Córnea , Epitélio Corneano , Queimaduras Oculares , Deficiência Límbica de Células-Tronco , Limbo da Córnea , Humanos , Doenças da Córnea/cirurgia , Autoenxertos , Queimaduras Oculares/induzido quimicamente , Queimaduras Oculares/cirurgia , Transplante de Células-Tronco/métodos , Transplante Autólogo , Queimaduras Químicas/cirurgia , Epitélio Corneano/transplante
5.
Int Ophthalmol ; 42(12): 3749-3762, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35984558

RESUMO

PURPOSE: Limbal stem cell deficiency (LSCD) is a rare but extremely relevant disease of the eye. LSCD patients often require a variety of surgical procedures, including keratoplasty in some cases. However, the outcome of these surgeries, including opacification and revascularization, is often frustrating due to LSCD relapse. METHODS: We developed a new surgical technique for the treatment of LSCD in which partial allogenic limbal transplantation (ALT) is carried out as part of penetrating keratoplasty (PK). After the PK, 1-8 slices from the limbal tissue of the donor graft are prepared and placed under the double running sutures attaching the corneal graft. This procedure was performed on 14 patients with LSCD, caused by severe ocular burn in 5 cases and by infection in 9. Between one and eight limbal transplants were used depending on the extension of the LSCD. RESULTS: All 14 patients showed stable or increased visual acuity after the ALT surgery compared to their preoperative visual acuity. All of the grafts were integrated into the superficial corneal layers without progression of corneal vascularization beyond the limbal grafts. The median follow-up period was 12 months on average. CONCLUSION: The ALT method seems to be a promising surgical procedure for the treatment of patients with LSCD. It can be properly carried out in the context of keratoplasty and does not require a separate donor tissue. The ALT grafts may offer the possibility of constructing a new limbal region, resulting in stable or even increased visual acuity and the absence of corneal vascularization.


Assuntos
Doenças da Córnea , Epitélio Corneano , Transplante de Células-Tronco Hematopoéticas , Limbo da Córnea , Doenças da Esclera , Humanos , Limbo da Córnea/cirurgia , Sobrevivência de Enxerto , Seguimentos , Doenças da Córnea/cirurgia , Transplante Autólogo , Epitélio Corneano/transplante
6.
Am J Ophthalmol ; 239: 244-268, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35314191

RESUMO

PURPOSE: Taking into consideration prior human experience with treating limbal stem cell deficiency (LSCD) with cultivated limbal epithelial cells (CLEC) from other countries, we have set a goal to optimize and standardize the techniques of CLEC preparation (called CALEC by our group) for the clinical trial in the United States. METHODS: We performed an extensive literature review of all human trials, case series, and reports involving autologous cultivated limbal epithelial cell transplantation. Allogeneic cultivated limbal epithelial cell transplantations were reported only when combined with autologous studies. We also searched prior animal data aiding in detailing regulatory toxicology requirements. RESULTS: Between 1997 and 2020, the analysis of human trials revealed 21 studies on autologous grafts, and 13 studies analyzing both autologous grafts and allogeneic grafts. Of a total of 34 studies, 6 studies used good manufacturing process (GMP) facilities, and 11 studies had no animal-derived products or murine feeder layers, whereas only 1 study had both. Overall, the treatment with autologous CLEC grafts was 68.9% successful. In total there were 6 preclinical studies using rabbits, serving as surrogate studies to assess the safety and toxicity of cultivated limbal epithelial cells for human trials. Based on prior human experience, we further optimized the manufacturing conditions with GMP-grade and serum and animal-free reagents, and developed cell characterization assays for the CALEC product release. CONCLUSIONS: These data were used to develop a novel and consistent manufacturing process using only qualified and validated reagents for performing the first clinical trial on CALEC transplantation to treat LSCD in the United States.


Assuntos
Doenças da Córnea , Epitélio Corneano , Limbo da Córnea , Doenças da Esclera , Animais , Transplante de Células , Células Cultivadas , Doenças da Córnea/cirurgia , Células Epiteliais/transplante , Epitélio Corneano/transplante , Humanos , Camundongos , Coelhos , Transplante de Células-Tronco/métodos , Transplante Autólogo
7.
Br J Ophthalmol ; 106(4): 461-466, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33328186

RESUMO

AIM: To compare the immunocytochemistry (ICC) on impression cytology of corneal surface epithelium after simple limbal epithelial transplantation (SLET) and conjunctival-limbal autograft (CLAU). METHODS: A prospective study of 20 patients above 1 year of age with chronic chemical burns, who underwent limbal stem cell transplantation (LSCT). They were divided equally in group A (SLET) and group B (CLAU). ICC was done for cytokeratin 3 (CK3) and cytokeratin 19 (CK19), preoperatively and postoperatively at 6 months. RESULTS: Four cases were excluded due to inadequate cellularity in preoperative or postoperative samples. On ICC analysis, in the remaining 16 patients mean CK3 and CK19 positivity changed from 2.06%±1.73% and 83.56%±8.69% preoperatively to 70.62%±13.2% (p<0.0001) and 5.93%±4.17% (p<0.0001), respectively, at 6 months post LSCT. In group A (8 patients) mean CK3 and CK19 positivity of 2%±1.8% and 84.5%±8.4% preoperatively changed to 70%±13.8% (p<0.0001) and 6.25%±5.1% (p<0.0001) at 6 months respectively. While in group B (8 patients), it was 2.12%±1.7% and 82.62%±9.4% preoperatively and 71.25%±013.5% (p<0.0001) and 5.62%±3.2% (p<0.0001) at 6 months. There was no significant difference in expression of CK3 (p=0.084) and CK19 (p=0.744) post SLET or CLAU.Three patients with complete reversion had clear corneas at 6 months. CONCLUSION: Reversion of the epithelium to corneal phenotype was documented post LSCT with no difference in expression of CK3 between the two procedures (SLET/CLAU).


Assuntos
Queimaduras Químicas , Doenças da Córnea , Epitélio Corneano , Doença Enxerto-Hospedeiro , Limbo da Córnea , Queimaduras Químicas/cirurgia , Doenças da Córnea/cirurgia , Epitélio Corneano/transplante , Humanos , Imuno-Histoquímica , Estudos Prospectivos , Transplante de Células-Tronco/métodos , Transplante Autólogo
8.
Middle East Afr J Ophthalmol ; 29(4): 232-234, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38162568

RESUMO

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.


Assuntos
Doenças da Córnea , Epitélio Corneano , Limbo da Córnea , Humanos , Doenças da Córnea/cirurgia , Autoenxertos , Seguimentos , Limbo da Córnea/cirurgia , Acuidade Visual , Âmnio/transplante , Transplante de Células-Tronco/métodos , Epitélio Corneano/transplante
9.
Yakugaku Zasshi ; 141(1): 55-60, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33390448

RESUMO

The eye is a complex organ with highly specialized constituent tissues derived from different primordial cell lineages. The retina develops from neuroectoderm via the optic vesicle, the corneal epithelium is descended from surface ectoderm, while the iris and corneal stroma have a neural crest origin. Recent work with pluripotent stem cells (PSCs) in culture has revealed a previously under-appreciated level of intrinsic cellular self-organization, with a focus on the retina and retinal cells. We recently demonstrated the generation from human induced pluripotent stem cells (iPSCs) of a self-formed ectodermal autonomous multi-zone (SEAM) of ocular cells. The concentric SEAM mimics whole-eye development because cell location within different zones is indicative of ocular cell lineage, spanning the ocular surface ectoderm, lens, neuro-retina, and retinal pigment epithelium. Therefore, SEAM represents a promising resource for new research of ocular morphogenesis and development. Moreover, we successfully isolated corneal epithelial progenitor cells and fabricated corneal epithelial tissue from PSCs. This approach has translational potential for treating severe corneal epithelial disease by transplantation of PSC-derived corneal epithelial tissue. To evaluate the efficacy and safety of the corneal epithelial tissue, we have started a first-in-human clinical study for patients with corneal epithelial stem cell deficiency, which began last year.


Assuntos
Diferenciação Celular/fisiologia , Epitélio Corneano , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Medicina Regenerativa/métodos , Linhagem da Célula , Células Cultivadas , Doenças da Córnea/terapia , Epitélio Corneano/citologia , Epitélio Corneano/transplante , Humanos , Organoides , Epitélio Pigmentado da Retina/citologia
10.
Cornea ; 40(1): 43-47, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32304432

RESUMO

PURPOSE: To report on the outcomes of recurrent pterygium treated by ipsilateral simple limbal epithelial transplantation (SLET), mitomycin, tenonectomy, and amniotic membrane transplantation. METHODS: A retrospective, interventional study was conducted including all patients with recurrent pterygium who underwent SLET surgery under a single surgeon using ipsilateral donor tissue with a minimum 6-month follow-up at Toronto Western Hospital, Canada. Outcome measures included the following: recurrence rates, best spectacle-corrected visual acuity, and postoperative complications. RESULTS: Ten eyes of 10 patients, aged 60.7 ± 18.5 years (range 23-79) with a mean follow-up time of 15.2 ± 10.0 months of which 50% (n = 5) were men, were included. Eight eyes (80%) had a history of 2 or less pterygium operations. Two patients had 3 and 5 previous pterygium operations, respectively. Concurrent limbal stem cell disease was noted in 6 eyes (60%). Average number of pterygium recurrences per eye was 1.9 ± 1.3 (range 1-5). Mean pre-op best-corrected visual acuity was 0.5 LogMAR (Snellen equivalent 20/60, range 20/20 to counting fingers). Best-corrected visual acuity remained the same or improved in 6 eyes (60%). Recurrence was noted in 1 eye (10%) with a history of 5 previous pterygium excisions and remained stable at the last follow-up. No patients required a second operation. CONCLUSIONS: Ipsilateral SLET with mitomycin, tenonectomy, and amniotic membrane transplantation is a novel technique to address recurrent pterygium. Concurrent limbal stem cell diseases are often present. Initial results demonstrate low recurrence. Visual improvement is modest. Stabilization of the ocular surface to improve vision is possible.


Assuntos
Alquilantes/administração & dosagem , Âmnio/transplante , Epitélio Corneano/transplante , Limbo da Córnea/citologia , Mitomicina/administração & dosagem , Pterígio/cirurgia , Cápsula de Tenon/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pterígio/fisiopatologia , Recidiva , Estudos Retrospectivos , Transplante de Células-Tronco , Transplante Autólogo , Resultado do Tratamento , Acuidade Visual/fisiologia , Adulto Jovem
11.
Br J Ophthalmol ; 105(2): 180-185, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32327416

RESUMO

BACKGROUND/AIM: To describe the clinical outcome of allogenic simple limbal epithelial transplantation (alloSLET) utilising tissue from cadaveric donor eyes after failed re-epithelialisation of the corneal surface. METHODS: Medical records of 14 eyes from 14 patients treated for persistent corneal epithelial defects with alloSLET were reviewed. The primary outcome measure was complete epithelialisation of the corneal surface. Secondary outcome measures were best corrected visual acuity (BCVA) and postoperative side effects due to surgery or medical therapy. RESULTS: Of the 14 eyes, 7 received alloSLET only and 7 alloSLET together with penetrating keratoplasty (PK). Thirteen (92.9%) of 14 eyes had an epithelialised corneal surface 3 and 6 months after surgery and 10 (71.4%) of 14 eyes displayed an epithelialised corneal surface 12 months after surgery. In both subgroups, alloSLET only and alloSLET with PK, respectively, 5 (71.4%) of 7 eyes had a stable corneal epithelium 12 months after surgery, respectively. Postoperatively, BCVA improved markedly in the whole patient collective. However, the increase was not significant when looking at the two individual subgroups. One patient lost his bandage contact lens several times within the first postoperative month and had a partial detachment of the amniotic membrane. The ocular surface of this patient failed to epithelialise. In three patients, limbal donor pieces translocated to the centre of the cornea, which possibly prolonged the improvement of BCVA. CONCLUSION: AlloSLET appears to be an effective treatment option in eyes with non-healing corneal epithelial defects when autologous limbal tissue is not available.


Assuntos
Doenças da Córnea/cirurgia , Epitélio Corneano/transplante , Limbo da Córnea/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aloenxertos , Cadáver , Doenças da Córnea/fisiopatologia , Epitélio Corneano/patologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Prednisolona/uso terapêutico , Reepitelização , Estudos Retrospectivos , Doadores de Tecidos , Resultado do Tratamento , Acuidade Visual/fisiologia
12.
J Tissue Eng Regen Med ; 15(2): 139-149, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33210832

RESUMO

This study aimed to evaluate the efficacy and safety of transplantation with human corneal limbal epithelial (HCLE) cell sheets cultured on carboxymethyl cellulose (CMC)-dopamine (DA)-coated substrates and harvested via enzymatic digestion of CMC with cellulase in a rabbit animal model of limbal stem cell deficiency (LSCD). Synthesized CMC-DA was pretreated onto the surface of culture plates. Then, HCLE cells were cultured on precoated CMC-DA and HCLE cell sheets were harvested using cellulase-containing cell culture medium. HCLE cell sheets were evaluated using a live/dead assay, histological examination, and immunofluorescence staining. For in vivo assessment, HCLE cell sheets were transplanted in a rabbit model of LSCD for 2 weeks to determine the effectiveness of the repair. Primary culture of HCLE cells stained positively for p63, cytokeratin (CK)15, and CK12. HCLE cell sheets were generated with a well-preserved morphology and transparency ranging in size from 15 to 19 mm after cellulase-assisted cell sheet generation. HCLE cell sheets uniformly stained positively for human mitochondria, p63, CK15, CK12, CK3/2p, and zonula occludens (ZO)-1. HCLE cell sheet transplantation in a rabbit model of LSCD improved the corneal opacity and neovascularization scores. Transplanted HCLE cell sheets stained positively for p63 and CK12. Transplantation of HCLE cell sheets harvested on CMC-DA coating combined with cellulase is a safe and efficient procedure for corneal epithelial regeneration in a rabbit model of LSCD. This system could enable a promising strategy to regenerate corneal epithelium by transplantation in ocular surface disorders.


Assuntos
Carboximetilcelulose Sódica/farmacologia , Doenças da Córnea , Dopamina/farmacologia , Células Epiteliais , Epitélio Corneano , Limbo da Córnea/metabolismo , Células-Tronco , Animais , Córnea , Doenças da Córnea/metabolismo , Doenças da Córnea/patologia , Doenças da Córnea/cirurgia , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/transplante , Epitélio Corneano/metabolismo , Epitélio Corneano/patologia , Epitélio Corneano/transplante , Xenoenxertos , Humanos , Limbo da Córnea/patologia , Coelhos
13.
BMJ Case Rep ; 13(12)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33318273

RESUMO

A 24-year-old young man presented to us with total limbal stem cell deficiency (LSCD) in the right eye 1 year post ocular chemical burn. The patient subsequently underwent limbal biopsy in the healthy contralateral eye and autologous simple limbal epithelial transplantation in the right eye. The patient was followed up with sequential imaging of the cornea with high-resolution anterior segment optical coherence tomography (HR-ASOCT) for 3 years. The serial HR-ASOCT imaging in the operated eye showed regeneration of the epithelium from the limbal transplant over the human amniotic membrane (hAM) with integration of the transplant within the cornea with subepithelial retention of the hAM. Over the long-term follow-up, thinning of the hAM and thickening of the epithelium was noted. At 3 years, the cornea maintained an intact epithelium with no signs of recurrence of LSCD.


Assuntos
Queimaduras Químicas/diagnóstico por imagem , Queimaduras Químicas/cirurgia , Epitélio Corneano/transplante , Queimaduras Oculares/diagnóstico por imagem , Queimaduras Oculares/cirurgia , Limbo da Córnea/diagnóstico por imagem , Limbo da Córnea/cirurgia , Tomografia de Coerência Óptica , Seguimentos , Humanos , Masculino , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
14.
Cornea ; 39 Suppl 1: S19-S27, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181721

RESUMO

Stevens-Johnson syndrome, ocular cicatricial pemphigoid, and severe thermal or chemical injury are considered severe ocular surface disorders (OSDs) because they affect the entire ocular surface, including corneal and conjunctival epithelial stem cells. In patients with severe OSDs, the long-term prognosis for limbal transplantation is poor, and the related corneal opacity and cicatrization lead to devastating visual impairment. To date, there is no standardized treatment to improve vision in cases with severe OSD. Investigating novel treatment methods for severe OSDs, our group began cultivated oral mucosal epithelial transplantation in 2002 and developed a limbal-supported rigid-type contact lens that can be applied as a nonsurgical treatment. When used in combination, these treatment methods make it possible to successfully restore vision in cases with severe OSDs.


Assuntos
Queimaduras Químicas/terapia , Lentes de Contato , Células Epiteliais/transplante , Queimaduras Oculares/induzido quimicamente , Mucosa Bucal/citologia , Penfigoide Mucomembranoso Benigno/terapia , Síndrome de Stevens-Johnson/terapia , Queimaduras Químicas/fisiopatologia , Células Cultivadas , Terapia Combinada , Doenças da Córnea/fisiopatologia , Doenças da Córnea/terapia , Epitélio Corneano/citologia , Epitélio Corneano/transplante , Queimaduras Oculares/fisiopatologia , Humanos , Penfigoide Mucomembranoso Benigno/fisiopatologia , Transplante de Células-Tronco , Síndrome de Stevens-Johnson/fisiopatologia , Transtornos da Visão/reabilitação , Acuidade Visual/fisiologia
15.
Cornea ; 39(12): 1588-1591, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32925431

RESUMO

PURPOSE: To assess the anatomic and visual results of the modified glueless simple limbal epithelial transplantation (G-SLET) in the treatment of unilateral limbal stem cell deficiency (LSCD). METHODS: This is a retrospective analysis of 2 patients who received G-SLET for corneal reepithelization after unilateral eye burn. After the recipient bed preparation on the eye with LSCD, radial symmetrical superficial incisions were applied to the corneal periphery. Next, short (1 mm) slightly oblique or horizontal tunnels were formed in every incision. The precut limbal pieces from the healthy eye were inserted into the tunnels with a scleral portion forward. At the end of surgery, the amniotic membrane was sutured to the sclera outside the corneal limbus with a single running suture. RESULTS: Slit lamp examination in the early postoperative period revealed that transplanted limbal pieces remained in place and were visible through the semitransparent amniotic membrane. The donor's eye had a small scar and light subconjunctival hemorrhage. Early and late postoperative periods were uneventful. Twelve months after surgery, the LSCD-affected cornea was entirely covered with tight and semitransparent epithelium. The donor's eye exhibited a small scar on the site of the biopsy. Visual improvement was achieved in case 2, but the vision did not improve due to the presence of a mature cataract in case 1. CONCLUSIONS: Modified G-SLET technique could be an option for LSCD treatment in patients with unilateral eye disease in cases when fibrin glue is not available for the surgeon.


Assuntos
Doenças da Córnea/cirurgia , Epitélio Corneano/transplante , Limbo da Córnea/citologia , Transplante de Células-Tronco/métodos , Âmnio/transplante , Doenças da Córnea/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Reepitelização , Estudos Retrospectivos , Microscopia com Lâmpada de Fenda , Retalhos Cirúrgicos , Técnicas de Sutura , Adesivos Teciduais , Transplante Autólogo , Acuidade Visual/fisiologia
16.
Methods Mol Biol ; 2145: 39-49, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542599

RESUMO

Cultured limbal epithelial stem cell transplantation is a clinical procedure used to regenerate the corneal epithelium in patients with limbal stem cell deficiency. The protocols used to expand limbal epithelial cells in vitro need to be optimized, since the scarcity of human ocular tissue donors is limiting the potential use of this procedure. Here, we describe a method to consecutively expand a single human limbal explant. With this method it is possible to obtain up to three limbal epithelial primary cultures from the same explant, thus increasing the efficiency of the in vitro cell culture.


Assuntos
Técnicas de Cultura de Células/métodos , Doenças da Córnea/terapia , Epitélio Corneano/crescimento & desenvolvimento , Limbo da Córnea/crescimento & desenvolvimento , Doenças da Córnea/patologia , Epitélio Corneano/citologia , Epitélio Corneano/transplante , Humanos , Limbo da Córnea/citologia , Células-Tronco/citologia
17.
Methods Mol Biol ; 2145: 143-157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542605

RESUMO

Amniotic membrane transplantation is an established therapeutic and biological adjunct for several clinical situations, including treatment of diabetic foot ulcers and ocular surface disease. However, poorly standardized and validated clinical preparation and storage procedures can render the final product highly variable and an unpredictable biomaterial. We have therefore developed a novel, standardized method for processing and dry-preserving amniotic membrane, minimizing biochemical, compositional, and structure damage to produce a potentially superior membrane suitable for clinical use. The intellectual property associated with this methodology was patented by the University of Nottingham and licensed to NuVision® Biotherapies which formed the basis of the Tereo® manufacturing process which is used to manufacture Omnigen®.


Assuntos
Âmnio/transplante , Córnea/crescimento & desenvolvimento , Doenças da Córnea/terapia , Regeneração/genética , Córnea/patologia , Epitélio Corneano/transplante , Oftalmopatias/patologia , Oftalmopatias/terapia , Humanos
18.
Am J Ophthalmol ; 217: 297-304, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32437668

RESUMO

PURPOSE: To compare outcomes of management in the early stage of severe chemical injury (grade 4 and worse; Dua classification) with amniotic membrane grafting (AMG) alone vs allogenic simple limbal epithelial transplantation (alloSLET). DESIGN: Retrospective comparative interventional case series. METHODS: Retrospective comparative interventional series. Records of patients with severe ocular chemical injury who underwent AMG alone (between 2009 and 2013) vs alloSLET (between 2013 and 2017) were analyzed for grade of injury, time of and interventions for epithelial healing, ocular surface status post healing (grade of symblepharon, and limbal stem cell deficiency [LSCD]), and type of and need for interventions in the chronic stage. RESULTS: Among patients presenting in early stage of severe chemical injury, 38 eyes (median age 11 years) managed with AMG alone were compared with 39 eyes (median age 8 years) managed with alloSLET. The mean time of presentation post injury was 33.85 ± 27.5 and 40.6 ± 23.5 days in the AMG and alloSLET group, respectively. The rate of epithelial healing was faster in the alloSLET group and the difference was noted to be statistically significant (odds ratio [OR] 0.966, P = .001). Similarly, the lower occurrence of LSCD (OR 0.137, P = .004) and need for keratoplasty (OR 0.093, P = .003) favored alloSLET over AMG. Final best-corrected visual acuity of >20/200 was achieved in 39.4% and 53.8% in the AMG and alloSLET groups, respectively. CONCLUSION: AlloSLET helps in faster epithelialization of the surface, thus reducing the need for subsequent surgeries in the chronic stage and aiding faster visual rehabilitation. The outcomes of alloSLET appear superior to amniotic membrane grafting alone and should be considered in eyes with grade 4 and above (Dua classification) chemical injuries in the early stage.


Assuntos
Âmnio/transplante , Queimaduras Químicas/cirurgia , Córnea/patologia , Transplante de Córnea/métodos , Epitélio Corneano/transplante , Queimaduras Oculares/cirurgia , Limbo da Córnea/citologia , Adolescente , Adulto , Idoso , Queimaduras Químicas/diagnóstico , Criança , Pré-Escolar , Córnea/cirurgia , Queimaduras Oculares/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Transplante Homólogo , Índices de Gravidade do Trauma , Resultado do Tratamento , Adulto Jovem
19.
J Ocul Pharmacol Ther ; 36(4): 238-246, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32077779

RESUMO

Purpose: The objective of this study was to describe the short-term results of allogenic transplantation of limbal stem cells expanded on amniotic membrane for the ocular surface reconstruction. Methods: Prospective nonrandomized, nonmasked study in a single ophthalmological center. Ten patients with bilateral total limbal stem cell deficiency (LSCD) were included. Expression and presence of ABCB5 and Δp63α in amniotic membrane-cultured limbal epithelial stem cells were analyzed, in relationship with clinical changes after allogenic transplantation. An objective evaluation was performed to determine corneal transparency and superficial vascularization. Results: In a median follow-up time of 11.6 months, 7 patients (70%) were considered as failure compared with the preoperative status. ABCB5 and Δp63α are expressed in similar amount in the limbal epithelial cells expanded in vitro and transplanted in patients with bilateral LSCD. Conclusions: Transplantation of allogenic epithelial limbal cells expanded in amniotic membrane could be considered in patients with LSCD due to burns or congenital etiologies such as aniridia, but its benefit is limited for patients with immunologic diseases.


Assuntos
Âmnio/transplante , Doenças da Córnea/etiologia , Epitélio Corneano/transplante , Limbo da Córnea/patologia , Células-Tronco/citologia , Transplante Homólogo/métodos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Adolescente , Adulto , Âmnio/citologia , Âmnio/metabolismo , Aniridia/complicações , Estudos de Casos e Controles , Córnea/irrigação sanguínea , Córnea/metabolismo , Doenças da Córnea/diagnóstico , Doenças da Córnea/metabolismo , Doenças da Córnea/cirurgia , Lesões da Córnea/complicações , Epitélio Corneano/anormalidades , Epitélio Corneano/citologia , Epitélio Corneano/metabolismo , Feminino , Seguimentos , Humanos , Limbo da Córnea/citologia , Limbo da Córnea/metabolismo , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Ensaios Clínicos Controlados não Aleatórios como Assunto/métodos , Estudos Prospectivos , Transplante de Células-Tronco/efeitos adversos , Células-Tronco/metabolismo , Células-Tronco/patologia , Fatores de Transcrição/metabolismo , Resultado do Tratamento , Proteínas Supressoras de Tumor/metabolismo , Adulto Jovem
20.
Br J Ophthalmol ; 104(2): 247-253, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31118185

RESUMO

PURPOSE: To conduct a systematic review on outcomes of three different techniques of autologous limbal stem cell transplantation (LSCT): conjunctival-limbal autografting (CLAu), cultivated limbal epithelial transplantation (CLET) and simple limbal epithelial transplantation (SLET), in unilateral limbal stem cell deficiency (LSCD). METHODS: Literature searches were conducted in MEDLINE (Ovid), Embase, Web of Science and Cochrane Central Register. Standard systematic review methodology was followed using Meta-analysis of Observational Studies in Epidemiology guidelines. Studies with a sample size of more than 10 eyes were included. The primary outcome measure of efficacy was restoration of a completely epithelised, stable and avascular corneal surface (anatomical success). The secondary outcome measure of efficacy was improvement in best-corrected visual acuity of two-lines or greater (functional success). RESULTS: The review identified 22 non-comparative case series, which included 1023 eyes. Ocular burns were the major (88%) indication for surgery. Overall, at a median postoperative follow-up of 1.75 years, autologous LSCT for unilateral LSCD showed anatomical and functional success rates of 69% and 60%, respectively, without any serious adverse events in the donor eye. The follow-up duration and indications for surgery were comparable across all groups (p>0.05). The anatomical and functional success rates of SLET (78%; 68.6%) and CLAu (81%; 74.4%) were comparable, and significantly better than those of CLET (61.4%; 53%; p=0.0048). CONCLUSION: Autologous LSCT is a safe and effective treatment for unilateral LSCD. In the absence of randomised controlled trials, existing evidence clearly suggests that clinical outcomes are better with SLET and CLAu as compared with CLET.


Assuntos
Túnica Conjuntiva/transplante , Doenças da Córnea/cirurgia , Transplante de Córnea/métodos , Epitélio Corneano/transplante , Limbo da Córnea/citologia , Transplante de Células-Tronco/métodos , Queimaduras Oculares/cirurgia , Humanos , Transplante Autólogo
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