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Background: Corneal transplantation is the most effective clinical treatment for irreversible corneal endothelial decompensation. However, while visual rehabilitation can be achieved by corneal transplantation, transplant rejection, poor postoperative visual acuity, and lack of suitable donor tissue are currently the greatest obstacles to corneal transplantation. As a result, endothelial cell-based therapy has emerged as an alternative to corneal transplantation treatment. Human induced pluripotent stem cells (hiPSCs) were induced to differentiate into human corneal endothelial cell (hCEC)-like cells in our study, which aimed to provide an experimental basis for studying the clinical translation and application of induced PSC (iPSC) to corneal endothelial cell (CEC) differentiation. Methods: A two-step method to convert hiPSCs into hCEC-like cells was applied in the study. First, the transforming growth factor beta (TGF-ß) and Wnt signaling pathways were regulated by adding SB4315542 and CHIR99021, and hiPSCs were induced to differentiate into neural crest cells (NCCs) by a chemically defined and serum-free in vitro induction method. Subsequently, NCCs were induced to differentiate into hCEC-like cells by adding B27, platelet-derived growth factor (PDGF)-BB, and XAV939 (Wnt pathway inhibitor) to CEC culture medium. Results: IPSCs were directionally differentiated into NCCs. During the process of differentiation, iPSCs gradually lost the monoclonal morphology of PSCs. Moreover, ß-catenin and SRY-related HMG-box gene 10 (SOX10) proteins were immunohistochemically expressed on the 7th day of differentiation. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) results demonstrated that the cells expressed SOX9, SOX10, nerve growth factor receptor (NGFR), human natural killer-1 (HNK-1), and ß-catenin, indicating that they were successfully directionally differentiated from iPSCs to NCCs. After 5-7 days of differentiation, the cells demonstrated a hexagonal morphology of monolayer tight junctions. Immunofluorescence results demonstrated that the cells expressed CEC indicator zonula occludens-1 (ZO-1) protein. QRT-PCR results demonstrated that the cells expressed collagen type IV alpha 1 (COL4A1), COL8A2, COL8A1, and ZO-1, which indicated that they were successfully directionally differentiated from NCC to CEC. Conclusions: Our study successfully provided a simple and efficient method with clear chemical composition and serum-free media to directionally differentiate hiPSCs into hCEC-like cells, thereby advancing the results of previous studies on directional transformation into epithelial cells.
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AIM: To compare if there is an improvement in visual functions with age-related cataracts between patients receiving a aspherical intraocular lens (IOL) based on corneal wavefront aberration and patients randomly assigned lenses. METHODS: A total of 124 eyes of 124 patients with age-related cataracts were placed in experimental group and a group receiving randomly assigned (RA) lenses. The experimental group was undergone Pentacam corneal spherical aberration measurement before surgery; the targeted range for residual total spherical aberration after surgery was set to 0-0.3 µm. Patients with a corneal spherical aberration <0.3 µm were implanted with a zero-spherical aberration advanced optics (AO) aspherical IOL and patients with an aberration ≥0.3 µm received a Tecnis Z9003 aspherical lens in experimental group. RA patients were randomly implanted with an AO lens or a Tecnis Z9003 lens. Three months after surgery total spherical aberration, photopic/mesopic contrast sensitivities, photopic/mesopic with glare contrast sensitivities, and logMAR vision were measured. RESULTS: Statistical analysis on logMAR vision showed no significant difference between two groups (P=0.413). The post-surgical total spherical aberration was 0.126±0.097 µm and 0.152±0.151 µm in the experimental and RA groups, respectively (P=0.12). The mesopic contrast sensitivities at spatial frequencies of 6, 12 and 18 c/d in the experimental group were significantly higher than of the RA group (P=0.00; P=0.04; P=0.02). The mesopic with glare contrast sensitivity in the experimental group at a spatial frequency of 18 c/d was also significantly higher vs the RA group (P=0.01). CONCLUSION: Pre-surgical corneal spherical aberration measurement in cataract patients followed by customized selection of aspherical IOL implants improved mesopic contrast sensitivities at high spatial frequencies, and thus is a superior strategy compared to the random selection of aspherical IOL implants.
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PURPOSE: To analyze the consistency between preoperatively estimated and postoperatively measured total spherical aberration and to evaluate the feasibility of personalized selection of an aspherical intraocular lens (IOL) based on the corneal spherical aberration measured by the Scheimpflug photography system (Pentacam). METHODS: A total of 47 patients (82 eyes) with age-related cataract received a comprehensive ophthalmologic examination. Corneal spherical aberration was measured by using the Scheimpflug photography system. Patients with corneal spherical aberration < or = 0.3 microm were implanted with a zero-spherical aberration advanced optics (AO) aspherical intraocular lens and those with corneal spherical aberration > 0.3 microm received a Tecnis ZA9003 aspherical lens (-0.27 microm spherical aberration). Preoperative total remnant spherical aberration was estimated and actual total spherical aberration was measured 3 months postoperatively. The consistency between preoperative and postoperative spherical aberration was analyzed by t-test, correlation analysis, and Blant-Altman plots. RESULTS: The estimated and measured values of total spherical aberration were (0.189 +/- 0.151) microm and (0.141 +/- 0.131) microm, with a statistical difference (t = 5.347, P < 0.01). For 45 eyes implanted with AO lenses, preoperatively estimated and postoperatively measured total spherical aberration were (0.268 +/- 0.137) microm and (0.214 +/- 0.103) microm. For 37 eyes implanted with Tecnis ZA9003, preoperative estimate of total spherical aberration was (0.092 +/- 0.103) microm and postoperative measured value was (0.054 +/- 0.106) microm. Statistical significance was noted, as was a positive linear correlation between preoperative and postoperative values (gamma = 0.846, P < 0.01). Bland-Altman analysis showed high consistency between the estimated and measured spherical aberration. CONCLUSION: The estimated total spherical aberration measured preoperatively differed from the value measured postoperatively, but the two values showed good agreement. It is clinically feasible to conduct personalized selection of aspherical IOL based on Scheimpflug photography system (Pentacam) to measure corneal spherical aberration.
