TRANSPLANTATION OF SUBRETINAL STEM CELL-DERIVED RETINAL PIGMENT EPITHELIUM FOR STARGARDT DISEASE: A Phase I Clinical Trial.

PURPOSE: To assess the safety of injecting human embryonic stem cell retinal pigment epithelial cell dose to treat Stargardt disease. METHODS: In this prospective, Phase I clinical trial, human embryonic stem cell retinal pigment epithelial cells in suspension were injected into the subretinal space in eyes with the worse best-corrected visual acuity (BCVA). After vitrectomy/posterior hyaloid removal, a partial retinal detachment was created and the human embryonic stem cell retinal pigment epithelial cells were administered. Phacoemulsification with intraocular lens implantation was performed in eyes with lens opacity. All procedures were optical coherence tomography-guided. The 12-month follow-up included retinal imaging, optical coherence tomography, visual field/electrophysiologic testing, and systemic evaluation. The main outcome was the absence of ocular/systemic inflammation or rejection, tumor formation, or toxicity during follow-up. RESULTS: The mean baseline BCVAs in the phacoemulsification and no phacoemulsification groups were similar (1.950 ± 0.446 and 1.575 ± 0.303, respectively). One year postoperatively, treated eyes showed a nonsignificant increase in BCVA. No adverse effects occurred during follow-up. Intraoperative optical coherence tomography was important for guiding all procedures. CONCLUSION: This surgical procedure was feasible and safe without cellular migration, rejection, inflammation, or development of ocular or systemic tumors during follow-up.

Diabetic Foot Wounds Treated With Human Amniotic Membrane and Low-level Laser Therapy: A Pilot Clinical Study.

BACKGROUND: Low-level laser therapy (LLLT) and human amniotic membrane (HAM) application have been shown to be viable options for use in wound healing. PURPOSE: This study sought to compare LLLT and HAM to a control treatment (hydrogel, saline, and gauze) in persons with diabetes mellitus (DM) and foot ulcers. METHODS: Using a prospective pilot clinical study design, patients receiving care at a health center that specializes in the treatment of diabetic foot wounds between November 2016 and August 2017 were recruited. Eligible patients had to be 30 to 59 years of age; diagnosed with type 2 DM (postprandial capillary glucose levels between 140 and 350 mg/dL); and have uninfected, granulating stage 2 or 3 foot ulcers measuring less than 7 cm by 3 cm. Immunosuppressed and malnourished patients or those with neoplasms or in critical condition were not eligible to participate. Patients received the control treatment (2 mg hydrogel, saline, and gauze), HAM (patches of thawed HAM, applied with overlapping edges), or LLLT (phototherapy session, 2 mg hydrogel, saline, and gauze) for 28 days. Variables, wound area measurements, Pressure Ulcer Scale for Healing (PUSH) scores, and Visual Analog Scale (VAS) scores were used to assess wound improvement progress and pain on days 7, 14, 21, and 28. Descriptive statistics were used to analyze the participant anthropometric and clinical profiles. The Kolmogorov-Smirnov test was used to analyze the sample distribution. The Kruskal-Wallis test with Dunn's post-test was used to evaluate differences in PUSH and VAS scores and wound size for intergroup analysis, and the Mann-Whitney U test was used for the same outcomes in intragroup analysis. The level of significance was 5% (P < .05). RESULTS: Twenty-seven (27) patients participated (mean age, 51.4 years; mean body mass index, 26.5 kg/m2), with 9 patients in each treatment group. No statistically significant differences were noted in clinical or anthropometric variables among the groups, but mean baseline wound areas were different (2.6 cm² for the control, 1.9 cm² for the LLLT, and 5.5 cm² for the HAM groups). Intragroup comparisons showed a significant reduction in PUSH score in the LLT group between days 0 and 21 (8.2 vs 4.9; P < .01) and days 21 to 28 (4.9 vs 3.2; P < .001). In all treatment groups the percent reduction was significantly different between days 7 and 28. No outcomes were significantly different between groups. CONCLUSION: Diabetic foot ulcer wound area as well as PUSH and VAS scores showed more improvement for patients with DM receiving LLLT or HAM than for the control group, but the differences were not significant. Larger studies are needed to compare these treatment modalities.

The effects of riboflavin and ultraviolet light on keratocytes cultured in vitro / Avaliação do efeito da riboflavina e luz ultravioleta sobre os ceratócitos in vitro

ABSTRACT Purpose: To culture quiescent human keratocytes and evaluate the effects of ultraviolet light and riboflavin on human corneal keratocytes in vitro. Methods: Keratocytes were obtained from remaining corneoscleral ring donor corneas previously used in corneal transplant surgeries and cultured in DMEM/F12 with 2% FBS until confluence. Characterization of cultured cells was performed by immunofluorescence analysis for anti-cytokeratin-3, anti-Thy-1, anti-α-smooth muscle actin, and anti-lumican. Immunofluorescence was performed before and after treatment of cultured cells with either ultraviolet light or riboflavin. Corneal stromal cells were covered with collagen (200 µL or 500 µL) and 0.1% riboflavin, and then exposed to ultraviolet light at 370 nm for 30 minutes. After 24 hours, cytotoxicity was determined using MTT colorimetric assays, whereas cell viability was assessed using Hoechst 33342 and propidium iodide. Results: Cell cultures achieved confluence in approximately 20 days. Expression of the lumican was high, whereas no expression of CK3, Thy-1, and α-SMA was observed. After crosslinking, MTT colorimetric assays demonstrated a low toxicity rate, whereas Hoechst 33342/propidium iodide staining demonstrated a low rate of apoptosis and necrosis, respectively, in all collagen-treatment groups. Conclusion: Keratocytes can be successfully cultured in vitro and characterized by immunofluorescence using lumican. MTT colorimetric assays, and Hoechst 33342, and propidium iodide staining demonstrated a higher rate of cell death in cells cultured without collagen, indicating collagen protects keratocytes from the cytotoxic effects of ultraviolet light.

RESUMO Objetivo: Avaliar o efeito da aplicação da luz ultravioleta e riboflavina sobre ceratócitos da córnea humana in vitro. Métodos: Os ceratócitos foram obtidos a partir das rimas corneoesclerais remanescentes da trepanação de córneas previamente utilizadas em cirurgias de transplante de córnea e cultivadas em meio DMEM/F12 com 2% de FBS até atingir confluência. As culturas de células foram caracterizadas por imunofluorescência com os anticorpos K3 (marcador de células epiteliais), Thy-1 (marcador de fibroblasto) SMA (marcador de miofibroblasto) e Lumican (marcador de ceratócitos). Imunofluorescência também foi feita após o tratamento. As células do estroma da córnea foram cobertas com colágeno (200 µL e 500 µL) e 0,1% de riboflavina e exposta a luz UVA a 370 nm por 30 minutos. Após 24 horas, citotoxicidade foi determinada por ensaio de MTT e a viabilidade celular foi feita por Hoechst 33342/Iodeto de propideo. Resultados: As culturas de células atingiram confluência em aproximadamente 20 dias. Imunofluorescência apontou alta expressão para o marcador de ceratócitos (Lumican) e expressão negativa par os marcadores de células epiteliais (K3), fibroblasto (Thy-1) e miofibroblasto (α-SMA). Após o cross linking a análise de MTT mostrou baixa taxa de toxicidade e com a coloração de Hoechst 33342/Iodeto de propideo baixa taxa de apoptose e necrose respectivamente em todos os grupos que continham colágeno. Conclusão: As culturas de ceratócitos foram obtidas e caracterizadas por imunofluorescência através do marcador Lumican com sucesso. O ensaio de MTT e a coloração por Hoechst 33342 e iodeto de propídio, apresentaram maior índice de morte celular nos grupos que não continham colágeno, provando que protege as células contra os efeitos da luz UVA.

Conjunctival epithelial cells cultivated ex vivo from patients with total limbal stem cell deficiency.

PURPOSE: Reconstruction of the ocular surface is challenging. As an alternative to mucosal and limbal epithelial, we study the feasibility of cultivated human conjunctival epithelial (HCjE) cells of patients with total limbal stem cell deficiency (LSCD). METHODS: We studied superior forniceal conjunctival biopsies harvested from 9 living donors with total LSCD of several etiologies who underwent surgery for ocular surface reconstruction. The conjunctival explants were cultivated on serum and growth factor supplemented DMEM/F12 under submerged conditions on denuded human amniotic membrane and tissue culture dishes. The area of cell growth was assessed. Cell morphology was analyzed by light microscopy, impression cytology, and transmission electron microscopy. Cultures were evaluated for epithelial cytokeratins (CK3, CK19), proliferation marker (Ki-67), and putative stem cells markers (ABCG2 and p63). Confocal immunofluorescence was also performed to assess CK3, CK19, Ki-67, ABCG2, and p63. RESULTS: The HCjE cells cultivated ex vivo were successfully expanded on denuded amniotic membrane but with a slower growth than in the tissue culture dish. Transmission electron microscopy showed stratified epithelium with microvilli, desmosomes, and hemidesmosomes. Impression cytology showed PAS+ cells that resembled goblet cells. Immunocytochemical analysis showed positivity for CK3, CK19, Ki-67, ABCG2, and p63. Confocal immunofluorescence was positive for CK3, CK19, Ki-67, ABCG2, and p63. CONCLUSIONS: Our results showed that it is possible to cultivate HCjE cells ex vivo of patients with ocular surface diseases. This method is important for ocular surface reconstruction in patients with bilateral total LSCD.

Transplantation of conjunctival epithelial cells cultivated ex vivo in patients with total limbal stem cell deficiency.

PURPOSE: To report the outcomes of transplantation of autologous conjunctival epithelial cells cultivated ex vivo (EVCAU) in patients with total limbal stem cell deficiency (LSCD). METHODS: EVCAU were cultivated on denuded human amniotic membrane and transplanted in 12 eyes of 10 patients with total LSCD. We evaluated the improvement in the defined clinical parameters of LSCD (loss of corneal epithelial transparency, superficial corneal neovascularization and epithelial irregularity/recurrent epithelial breakdown), vision acuity, impression cytology, immunocytochemical analysis (CK3/CK19), and the appearance of a regular hexagonal basal layer of cells on corneal confocal microscopy. Histologic and immunohistochemical features were studied in 3 corneal buttons of patients submitted to penetrating keratoplasty after EVCAU. RESULTS: Cultivated conjunctival epithelium formed 4 to 5 layers with the formation of basement membrane-like structures. Immunocytochemical analysis showed positivity for CK3, CK19, MUC5AC, Ki-67, P63, and ABCG2. The improvement of the clinical parameters for this treatment in our cohort was 10 of 12 (83.3%) in a mean follow-up time of 18.5 months (range, 15-26 months), and these eyes showed an improvement in impression cytology, immunocytochemistry, and in vivo confocal analysis. Corneal buttons showed a well-formed epithelium with 5 to 6 layers, with rare cells periodic acid-Schiff+, and positivity for CK3, CK19, P63, connexin 43, and MUC5AC. CONCLUSION: We demonstrated the preliminary results of transplantation of EVCAU for corneal surface reconstruction in cases with total LSCD. Future studies are needed to further assess the long-term efficacy of this procedure.