Settling characteristics of scleral lenses in Chinese adults with refractive error.

PURPOSE: To investigate the settling characteristics of a scleral lens in Chinese adults with refractive error and to provide guidance for its clinical application. METHODS: A total of 21 healthy Chinese adults (27.2 ± 4.1 years) with refractive error were enrolled in this study. The average spherical equivalent was -5.50 ± 2.92 D. Subjects were fitted with 15.6 mm diameter scleral lenses. The central post-lens tear thickness (PoLTT) was measured immediately after lens placement, 30, 60, 120, and 240 min after lens insertion at the dispensing visit and immediately after lens placement and 240 min after three months through optical coherence tomography. Statistical analyses were conducted using repeated measures analysis of variance and paired-t test. RESULTS: At the dispensing visit, the amount of settling after 240 min of lens wear was 126 ± 33 µm. After three months, the amount of settling was 98 ± 55 µm after 240 min. No significant difference was detected in the PoLTT immediately after lens placement between the dispensing visit and after three months (t = -0.246, p = 0.807), while a significant difference was noted at 240 min after lens insertion (t = -6.575, p < 0.001). The amount of settling was higher at the dispensing visit than that after three months (average difference = 28 ± 63 µm, t = 2.733, p = 0.01). The prediction model of PoLTT over time was y = 26.263-0.690 × t + 0.001 × t2 + 0.926 × y30 (R2 = 0.939), where y denotes the predicted PoLTT at t min after lens insertion, y30 denotes the PoLTT at 30 min after lens insertion. CONCLUSION: For the investigated small-diameter scleral lens (material: Boston XO, diameter: 15.6 mm, four-zone and periphery toric design), the PoLTT decreased over time after lens insertion in Chinese adults with refractive error, and the amount of settling varied among individuals (range: 71-204 µm). The amount of settling did not increase further after three months, indicating the long-term fitting stability of the scleral lens. Practitioners could estimate the PoLTT using the prediction model based on the PoLTT at 30 min after wearing lenses.

Metrics of Anterior Sclera in Normal Chinese Adults: Anterior Segment Imaging Using the Swept-Source Optical Coherence Tomography.

PURPOSE: To measure the corneoscleral limbus and anterior sclera parameters of normal Chinese adults by swept-source optical coherence tomography (OCT). MATERIALS AND METHODS: In this cross-sectional study, a total of 56 Chinese subjects with ametropia were evaluated in the Eye Hospital of Wenzhou Medical University from September 2020 to December 2020, including 26 (46.4%) men, with an average age of 24.7±1.8 years old. The OCT SS-1000 (CASIA, Tomey, Tokyo, Japan) was used to measure the sagittal height, corneoscleral junction (CSJ) angle, and scleral angle. RESULTS: The chord was across the corneal center and the line connecting the center of the cornea and the center of the chord was perpendicular to the chord. The mean sagittal height at chord lengths of 10.0, 12.3, and 15.0 mm were 1,756±72, 2,658±110, and 3,676±155 µm, respectively. The absolute values of the differences between horizontal and vertical meridians at three chord lengths were 54±40, 70±67, and 117±95 µm, respectively. One-way analysis of variance showed that the differences of CSJ angles at 12.3-mm chord and scleral angles at 15.0-mm chord in the four segments were statistically significant ( F values were 32.01 and 13.37, respectively, both P <0.001). The CSJ angles from low to high were 176.53±2.14° (nasal), 178.66±1.84° (inferior), 179.13±1.20° (temporal), and 179.31±1.68° (superior), and 87.5% of the nasal angles were less than 179°. The scleral angles from high to low were 38.35±2.47° (temporal), 38.26±3.37° (superior), 35.37±3.10° (nasal), and 35.30±4.71° (inferior). CONCLUSIONS: The morphology of corneoscleral limbus and anterior sclera is asymmetrical in normal Chinese adults. The nasal side of the corneoscleral limbus has the largest angle, and the superior and temporal sides of the scleral angle are larger.

Low vision aids and age are associated with Müller-Lyer illusion in congenital visually impaired children.

Background: The correlation between visual impairment and Müller-Lyer illusion is not yet elucidated. This study aimed to explore the connection between visual status, age, and the intensity of Müller-Lyer illusion in congenitally visually impaired and visually healthy children aged 4-17 years. Additionally, the developmental trends were compared. Methods: This cross-sectional study included 125 visually impaired children (age: 10.59 ± 4.05 years), among them, 53 had utilized low vision aids (LVAs) and 133 healthy controls (age: 11.33 ± 3.39 years). The participants were presented with Müller-Lyer illusion stimuli via binocular and engaged in a two-alternative forced choice task to quantify the illusion intensity. Pertinent factors including age, gender, residence, binocular distant best-corrected visual acuity and LVAs usage history, were assessed. Results: The visually impaired group exhibited significantly elevated illusion intensity compared to the healthy group (9.74 ± 2.89% vs. 5.42 ± 3.81%, p < 0.001), and visually impaired participants who had used LVAs exhibited significantly lower intensity compared to those had not (9.13 ± 3.00% vs. 10.19 ± 2.74%, p = 0.043). Multivariate generalized estimation equations revealed that visual impairment [odds ratio (OR) = 2.75, p < 0.001] and age (OR = 0.60, p < 0.001) were associated with illusion intensity in all participants, while history of LVAs usage (OR = 0.49, p = 0.045) and age (OR = 0.61, p < 0.001) were negatively correlated in visually impaired group. A significantly negative correlation was found between illusion intensity and age 4-17 years in the subgroups of visually impaired who had used LVAs (Y = -0.54X + 15.06, R2 = 0.56), who had not used (Y = -0.49X + 15.24, R2 = 0.51), and healthy controls (Y = -0.50X + 11.18, R2 = 0.21); all p-values were < 0.001. Conclusion: Children aged 4-17 years afflicted with congenital visual impairment exhibited a heightened intensity of Müller-Lyer illusion compared to visually normal counterparts, LVAs usage experience could reduce this higher intensity. The developmental trajectory of illusion intensity declined consistently with age across all three groups. The abnormal visual experiences during early-life may adversely affect integration in congenitally visually impaired children, and LVAs could facilitate this functional development.

Repeatability and agreement of AOCT-1000 M, RTVue XR and IOL master 500 in measuring corneal thickness mapping and axial length applying principle of optical coherence tomography.

PURPOSE: To evaluate the repeatability and agreement of Fourier-domain optical coherence tomography (AOCT-1000 M and RTVue XR) and partial coherence interferometry biometer (IOL Master 500) in measuring corneal thickness mapping and axial length respectively. METHODS: Corneal thickness was measured by AOCT-1000 M and RTVue XR. Axial lengths were measured by AOCT-1000 M and IOL Master 500. The repeatability and agreement of corneal thickness and axial length were calculated in two groups of devices. The intraclass correlation coefficient (ICC) was used to verify the repeatability of the device. The 95% confidence interval of the difference compared to the set cut-off value was used to verify the agreement between the two devices. RESULTS: A total of 60 subjects with 58 eyes were included. The central corneal thickness measured by AOCT-1000 M and RTVue XR were 504.46 ± 42.53 µm and 504.43 ± 42.89 µm respectively. The average difference between groups was 0.03 ± 4.58 µm, and the 95% confidence interval was (-1.17, 1.24), which was far less than the set threshold value of 15 µm (P < 0.001). Both RTVue XR and AOCT-1000 M had very good ICC values of central corneal thickness (0.998 and 0.994, respectively). The average axial lengths measured by AOCT-1000 M and IOL Master 500 were 24.28 ± 1.25 mm and 24.29 ± 1.26 mm respectively and the 95% confidence interval was (-0.02, 0.01), which was less than the set threshold value of 0.15 mm (P < 0.001). The ICC for both devices were 1.000. CONCLUSION: Good repeatability and agreement were seen in measurements of central corneal thickness and axial length by AOCT-1000 M.

Development of a new 17-item Asthenopia Survey Questionnaire using Rasch analysis.

AIM: To develop the 17-item Asthenopia Survey Questionnaire (ASQ)-17 by Rasch analysis, and to generate a predictiveness score. METHODS: Totally 739 participants were recruited and 680 were involved in the result analysis in this prospective, cross-sectional study. Three rounds of Rasch analysis were used to analyze the psychometric characteristics of items and options. RESULTS: Phase 1 assessed the original ASQ-19, adjusted the item scoring mode to a four-point Likert response rating scale and combined the 18th and 19th items into a new item. Phase 2 deleted the 11th item. Phases 3 and 4 assessed the new ASQ-17. All the evaluation indexes of ASQ-17 were acceptable. The Infit and Outfit MnSq values of items were 0.67-1.48, the variance explained by the principal component and the unexplained variance explained by the first contrast were 53.90%-59.40% and 1.50-1.80 in three dimensions. The curve peaks of scores in each dimension were separated and in the same order. The PSR and PSI values were 2.80 and 0.89, respectively. The mean scores of dimensions A (9.5±4.1 vs 3.5±3.2), B (7.3±3.3 vs 2.5±2.7), C (4.3±2.2 vs 1.4±2.0) and total (21.1±8.1 vs 7.4±7.0) in asthenopia participants were significantly higher than those without asthenopia (all P<0.001). The area under the curve in two groups was 0.899 (P<0.001). Youden's index was up to the maximum value of 0.784 when the cut-off value was 12.5. CONCLUSION: ASQ-17 has stronger option sorting and suitability than ASQ-19. It is an effective assessment tool for asthenopia with an optimal cut-off threshold value of 12.5, which is suitable for diagnosis and curative effect evaluation.

Best-corrected visual acuity results facilitate molecular diagnosis of infantile nystagmus patients harboring FRMD7 mutations.

The visual function of patients with infantile nystagmus (IN) can be significantly decreased owing to constant eye movement. While, reaching a definitive diagnosis becomes a challenge due to genetic heterozygous of this disease. To address it, we investigated whether best-corrected visual acuity (BCVA) results can facilitate the molecular diagnosis of IN patients harboring FRMD7 mutations. 200 patients with IN from 55 families and 133 sporadic cases were enrolled. Mutations were comprehensively screened by direct sequencing using gene-specific primers for FRMD7. We also retrieved related literature to verify the results based on our data. We found that the BCVA of patients with IN harboring FRMD7 mutations was between 0.5 and 0.7, which was confirmed by data retrieved from the literature. Our results showed that BCVA results facilitate the molecular diagnosis of patients with IN harboring FRMD7 mutations. In addition, we identified 31 FRMD7 mutations from the patients, including six novel mutations, namely, frameshift mutation c.1492_1493insT (p.Y498LfsTer14), splice-site mutation c.353C > G, three missense mutations [c.208C > G (p.P70A), c.234G > A (p.M78I), and c.1109G > A (p.H370R)], and nonsense mutation c.1195G > T (p.E399Ter). This study demonstrates that BCVA results may facilitate the molecular diagnosis of IN patients harboring FRMD7 mutations.

Prevalence and determinants of asthenopia among ophthalmologists in China: a national cross-sectional survey.

Introduction: The role of ophthalmologists is defined by tasks requiring visual effort, emphasizing the importance of examining their condition within the realm of occupational visual health. Our goal was to explore the occurrence of asthenopia among Chinese ophthalmologists and identify contributing factors through the use of a reliable and validated survey instrument. Methods: A national cross-sectional online survey was carried out in June 2017, involving 6,220 practicing ophthalmologists in China. Utilizing an 11-item Asthenopia Survey Questionnaire with established reliability and validity. Prevalence rates of asthenopia among subgroups categorized by age, gender, hospital classification, physician level, daily near vision activity duration, sleep duration, sleep quality, presbyopia status, and history of eye surgery were determined using the independent t-test, chi-square test and bonferroni test. Multiple logistic regression analysis was employed to pinpoint independent factors linked to asthenopia. Results: Out of the 5,009 ophthalmologists who completed the survey, a 40.7% prevalence of asthenopia was identified. Multivariate analysis revealed that good sleep quality (OR: 0.24, 95%CI: 0.20-0.30), moderate sleep quality (OR: 0.47, 95%CI: 0.38-0.59), engaging in daily near vision activities for less than 7 h (OR: 0.76, 95%CI: 0.68-0.86), having daily sleep duration exceeding 7 h (OR: 0.87, 95%CI: 0.77-0.98), and working in tertiary hospitals (OR: 0.88, 95%CI: 0.78-0.99) were protective factors against asthenopia. Conversely, presbyopia was identified as a risk factor (OR: 1.33, 95%CI: 1.04-1.70). All calculated p values were below 0.05. Age, gender, physician level, and eye surgery history were not related factors. Conclusion: Asthenopia is prevalent among Chinese ophthalmologists, with employment in tertiary hospitals providing a protective effect and presbyopia is a risk factor. Preventive strategies include improving sleep quality, restricting daily near vision activity to under 7 h, and extending daily sleep duration to over 7 h. Further investigation is needed to explore the protective implications of working in tertiary hospitals.

Performance of the AIDRScreening system in detecting diabetic retinopathy in the fundus photographs of Chinese patients: a prospective, multicenter, clinical study.

Background: Diabetic retinopathy (DR) is the leading cause of blindness in the working-age population worldwide, and there is a large unmet need for DR screening in China. This observational, prospective, multicenter, gold standard-controlled study sought to evaluate the effectiveness and safety of the AIDRScreening system (v. 1.0), which is an artificial intelligence (AI)-enabled system that detects DR in the Chinese population based on fundus photographs. Methods: Participants with diabetes mellitus (DM) were recruited. Fundus photographs (field 1 and field 2) of 1 eye in each participant were graded by the AIDRScreening system (v. 1.0) to detect referable DR (RDR). The results were compared to those of the masked manual grading (gold standard) system by the Zhongshan Image Reading Center. The primary outcomes were the sensitivity and specificity of the AIDRScreening system in detecting RDR. The other outcomes evaluated included the system's diagnostic accuracy, positive predictive value, negative predictive value, diagnostic accuracy gain rate, and average diagnostic time gain rate. Results: Among the 1,001 enrolled participants with DM, 962 (96.1%) were included in the final analyses. The participants had a median age of 60.61 years (range: 20.18-85.78 years), and 48.2% were men. The manual grading system detected RDR in 399 (41.48%) participants. The AIDRScreening system had a sensitivity of 86.72% (95% CI: 83.39-90.05%) and a specificity of 96.09% (95% CI: 94.14-97.54%) in the detection of RDR, and a false-positive rate of 3.91%. The diagnostic accuracy gain rate of the AIDRScreening system was 16.57% higher than that of the investigator, while the average diagnostic time gain rate was -37.32% lower. Conclusions: The automated AIDRScreening system can detect RDR with high accuracy, but cannot detect maculopathy. The implementation of the AIDRScreening system may increase the efficiency of DR screening.

A new antioxidant made from a pterostilbene functionalized graphene nanocomposite as an efficient treatment for dry eye disease.

Dry eye disease is a common condition that affects the eyes. It is caused by problems with the tear film and the tear dynamics. Dry eye can be caused by an increase in the amount of reactive oxygen species (ROS) in the corneal epithelium. The treatment for dry eye typically focuses on relieving the uncomfortable symptoms by using eye drops such as artificial tears, antibiotics, and by using anti-inflammatory/immunosuppressive agents such as cyclosporine, and lifitegrast. However, the recovery of patients with dry eye can take several years particularly if the symptoms are severe. This is because the present treatment approaches for dry eye are not based on its cause, e.g., the oxidative stress arising from the rapid increase in ROS. This work describes a new type of antioxidant made from pterostilbene (PS) and carboxyl-chitosan modified graphene (CG). The use of a hydrophilic two-dimensional CG nanosheet to improve the properties of PS is reported. Superior enhanced properties including better cellular permeability, long sustained release period (over 30 h), and antioxidant properties, were realized by using PS-CG. A hyperosmotic (HS) damaged human corneal epithelial cell (HCEC) model was used for antioxidant tests. This model has an intracellular ROS level 4 times more than that of a control group. The ROS content was declined efficiently to the same amount as normal cells in the PS-CG treated HS group. There was a significant decline in the content of lactate dehydrogenase (LDH) and the apoptosis rate of HCEC in the PS-CG treated HS group when compared to that seen in the HS model. Real-time polymerase chain reaction (PCR) and western blots (WB) were used to understand the antioxidant mechanism of PS-CG. The results showed that the antioxidant was working by activating the Keap1-Nrf2-ARE signalling pathway. In vivo testing testing using a dry eye mouse model suggested that the PS-CG acted as an efficient antioxidant. More tear production and healthier corneal and conjunctival epithelial cells were achieved when PC-CG was applied to this model. The use of PS-CG could be a new strategy for treating dry eye and other ocular diseases caused by ROS.

Myopia progression and stabilization in school-aged children with single-vision lenses.

PURPOSE: To investigate the longitudinal changes in myopia from onset to stabilization in school-aged children with single-vison lenses (SVLs). METHODS: The medical records of patients wearing SVLs with long-term follow-up data between 2006 and 2016 were retrospectively reviewed. The patients who were 6-10 years old at the initial visit and 16 years old at the last assessment were included and analysed. The periods of progression and stabilization of myopia were evaluated by plotting fitted curves of the changes in spherical equivalent (SE). RESULTS: Seven hundred and seventy-three patients (median initial age 9 years) were accessed over an average of 7 years (IQR, 6-7 years). The initial mean SE was -1.92 ± 1.57 D and increased to -6.05 ± 2.14 D at 16 years old. The average age at myopia stabilization was 14.6 years, and girls slightly stabilized earlier than boys. 73.7% of the 6-year-olds and 85.7% of the 7-year-olds had high myopia at 16 years old, and the risk decreased each year from 7 to 10 years old. Children who had SE greater than -4 D up to 10 years had 89.0% risk of high myopia at 16 years old. Children with SE between -0.5 D and -2 D still had 34% risk of developing high myopia at 16 years old. CONCLUSION: This study provides a comprehensive picture of myopia progression from onset to stabilization in school-aged children with SVLs in China. All children who have myopia onset below 10 years of age were at risk for high myopia, and children who have myopia onset below 8 years of age require more attention.

Lb2Cas12a and its engineered variants mediate genome editing in human cells.

Cas12a-mediated targeted genome engineering strategies have enabled a broad range of research and clinical applications. However, the limited target-selection spectrum and low activity/fidelity remain a bottleneck for its widespread application in precision site-specific human genome editing. Therefore, there exists an acute need to identify novel Cas12a nucleases with improved features for genome editing. By screening a range of candidate Cas12a nucleases, here we demonstrate that Lb2Cas12a possesses genome editing activity in human cells and it has greater flexibility in PAM (5'-BYYV-3') selection. Furthermore, we engineered Lb2Cas12a to generate variants (Lb2Cas12a-RVR and Lb2Cas12a-RR), which greatly expands the target-selection spectrum. Our study illustrated that Lb2Cas12a could be harnessed as additional genome editing tool for the manipulation of human genome.

Development of a Simple and Quick Method to Assess Base Editing in Human Cells.

Base editing is a form of genome editing that can directly convert a single base (C or A) to another base (T or G), which is of great potential in biomedical applications. The broad application of base editing is limited by its low activity and specificity, which still needs to be resolved. To address this, a simple and quick method for the determination of its activity/specificity is highly desired. Here, we developed a novel system, which could be harnessed for quick detection of editing activity and specificity of base editors (BEs) in human cells. Specifically, multiple cloning sites (MCS) were inserted into the human genome via lentivirus, and base editing targeting the MCS was performed with BEs. The base editing activities were assessed by specific restriction enzymes. The whole process only includes nucleotide-based targeting the MCS, editing, PCR, and digestion, thus, we named it NOTEPAD. This straightforward approach could be easily accessed by molecular biology laboratories. With this method, we could easily determine the BEs editing efficiency and pattern. The results revealed that BEs triggered more off-target effects in the genome than on plasmids including genomic indels (insertions and deletions). We found that ABEs (adenine base editors) had better fidelity than CBEs (cytosine base editors). Our system could be harnessed as a base editing assessment platform, which would pave the way for the development of next-generation BEs.

Refractive status and prevalence of myopia among Chinese primary school students.

BACKGROUND: The aim of this study was to investigate the prevalence of myopia in key (university-oriented) and non-key elementary schools in China using a traditional and a new criterion for myopia diagnosis in an epidemiological study. METHODS: This school-based, cross-sectional study examined students from four key schools and seven non-key schools. Non-cycloplegic autorefraction and visual acuity (VA) were performed on each student. Myopia was defined as a spherical equivalent (SE) refractive error not better than -1.00 D. A questionnaire was also administered. RESULTS: Of the 13,220 students examined, 6,546 (49.5 per cent) had myopia using the criterion of SE not better than -1.00 D. However, 2,246 (34.3 per cent) of these myopes had VA ≥ 0 logMAR in both eyes, indicating they were not functioning as myopes. Thus, a second myopia criterion was adopted: SE refractive error not better than -1.00 D + uncorrected VA ≥ 0 logMAR in at least one eye. By this definition, only 32.5 per cent of the overall sample had myopia. Students in key schools had a higher prevalence of myopia than those in non-key schools (53.8 per cent versus 44.7 per cent) by the initial criterion. By the new criterion, the prevalence of myopia was 41.2 per cent versus 22.7 per cent. Myopia was equal in grade 1 of both school types, but accelerated faster in key schools, where there was a much higher prevalence of myopia by fourth grade, and continued up to 79.2 per cent prevalence by sixth grade based on SE refractive error not better than -1.00 D. CONCLUSION: Students in more competitive university-oriented elementary schools developed myopia much faster than those in regular schools, although they started with the same level of myopia. Since one-third of the 'myopes' had VA ≥ 0 logMAR in both eyes, they would not be prescribed a correction, or be clinically treated as myopes. A new criterion of SE refractive error not better than -1.00 D + uncorrected VA ≥ 0 logMAR in at least one eye was tested. This criterion is more clinically appropriate and could be used in future epidemiological studies.

A Nurse's Perspective on Visual Rehabilitation of Outpatients With Low Vision in China.

PURPOSE: The purposes of the study were to analyze patient use and satisfaction with low vision aids (LVAs) at the Wenzhou Medical University Low Vision and Rehabilitation Center and to assess the promotion of visual rehabilitation services as a new responsibility for nurses in China. METHODS: Records of 178 patients with low vision (LV) from the Low Vision and Rehabilitation Center examined between October 2015 and October 2016 included basic patient information (e.g., age, diagnosis, visual acuity, educational level) and use of LVAs (patients' own aids, daily duration of LVA use, or refusal to use aids). RESULTS: Sixty percent owned LVAs. Of these, 66% were obtained from a hospital, 26% were obtained from commercial stores, and others were obtained from government or gifts. Patients reported that use of LVAs was reduced because of visual fatigue (39%), inconvenience (22%), and lack of benefit (12%). Reasons for the 40% who had never used visual rehabilitation were nonreferral by doctors (76%), refusal because of inconvenience, discomfort and cosmetics (20%), or a preference for other treatments (4%). CONCLUSIONS: Greater awareness of LV rehabilitation by nurses, ophthalmologists, patients, and the public is necessary. Additional government support for LV rehabilitation is also required.

The Needs for Visual Improvement of Patients Presented at Low-Vision Center in Wenzhou, China.

PURPOSE: To characterize the needs for visual improvement of new-visit patients with low vision. METHODS: This cross-sectional study collected detailed information of patients presented at low-vision center of the Eye Hospital of Wenzhou Medical University between January 2015 and January 2017. A questionnaire interview, including demographic information and needs for visual improvement, was conducted before ophthalmology examinations. RESULTS: The main need for visual improvement was engagement in hobbies (68.9%), followed by reading (20.9%), engaging in occupation (20.1%), and watching TV or movies (17.1%). Less than 10% of patients mentioned the demand of using public transportation (5.8%), doing housework (3.7%), writing (1.9%), walking on irregular surfaces (1.5%), driving (1.1%), and others (2.4%). Women were significantly associated with a concern for performing hobbies (OR 1.45, 95% CI 1.0-2.0) but associated with lower odds of reading (OR 0.46, 95% CI 0.3-0.7). Older subjects were more willing to choose hobbies (OR 1.35 (per 10-year increase), 95% CI 1.3-1.4), reading (OR 1.11 (per 10-year increase), 95% CI 1.0-1.2), watching TV or movies (OR 1.4 (per 10-year increase), 95% CI 1.3-1.6), and housework (OR 1.21 (per 10-year increase), 95% CI 1.0-1.5) than younger individuals. In comparison with younger participants, older individuals were less likely to choose occupation (OR 0.53 (per 10-year increase), 95% CI 0.5-0.6). No significant association was found between visual acuity and needs for visual improvement. CONCLUSION: Hobbies, reading, engaging in occupation, and watching TV were the most common needs for visual rehabilitation in patients with visual impairment. Gender and age showed a modest influence on the choice of different needs.

Short ragweed pollen promotes M2 macrophage polarization via TSLP/TSLPR/OX40L signaling in allergic inflammation.

This study was to explore the role and mechanism of macrophages in pollen-triggered allergic inflammation. A murine model of short ragweed (SRW) pollen-induced experimental allergic conjunctivitis (EAC), and bone marrow (BM)-macrophages cultures were used. Typical allergic manifestations and TSLP-stimulated Th2 hyperresponse were observed in ocular surface of EAC model in wild-type (WT) mice induced by SRW. The M2 phenotype markers, Arg1, Ym1 and FIZZ1, were highly expressed by conjunctiva and draining cervical lymph nodes (CLNs) of WT-EAC mice when compared with controls, as evaluated by RT-qPCR and Immunofluorescent double staining with macrophage marker F4/80. The stimulated expression of TSLPR and OX40L by macrophage was detected in conjunctiva and CLNs by RT-qPCR, double staining, and flow cytometry. M2 macrophages were found to produce TARC and MDC. In contrast, EAC model with TSLPR-/- mice did not show allergic signs and any increase of Th2 cytokines (IL-4, IL-5 and IL-13) and M2 markers. In vitro cultures confirmed that SRW extract stimulates expression of TSLPR, OX40L, TARC, MDC, and three M2 markers by BM-macrophages from WT mice, but not from TSLPR-/- mice. These findings demonstrate that SRW pollen primes macrophage polarization toward to M2 phenotype via TSLP/TSLPR/OX40L signaling to amplify allergic inflammation.

Efficient Human Genome Editing Using SaCas9 Ribonucleoprotein Complexes.

Genome editing using RNA-guided nucleases in their ribonucleoprotein (RNP) form represents a promising strategy for gene modification and therapy because they are free of exogenous DNA integration and have reduced toxicity in vivo and ex vivo. However, genome editing by Cas9 nuclease from Staphylococcus aureus (SaCas9) has not been reported in its RNP form, which recognizes a longer protospacer adjacent motif (PAM), 5'-NNGRRT-3', compared with Streptococcus pyogenes Cas9 (SpCas9) of 5'-NGG-3' PAM. Here, SaCas9-RNP-mediated genome editing is reported in human cells. The SaCas9-RNP displayed efficient genome editing activities of enhanced green fluorescent protein (EGFP) coding gene as well as three endogenous genes (OPA1, RS1, and VEGFA). Further, SaCas9-RNP is successfully implemented to correct a pathogenic RS1 mutation for X-linked juvenile retinoschisis. It is also shown that off-target effects triggered by SaCas9-RNP are undetectable by targeted deep sequencing. Collectively, this study demonstrates the potential of SaCas9-RNP-mediated genome editing in human cells, which could facilitate genome-editing-based therapy.

IL-27 signaling deficiency develops Th17-enhanced Th2-dominant inflammation in murine allergic conjunctivitis model.

BACKGROUND: While most studies focus on pro-allergic cytokines, the protective role of immunosuppressive cytokines in allergic inflammation is not well elucidated. This study was to explore a novel anti-inflammatory role and cellular/molecular mechanism of IL-27 in allergic inflammation. METHODS: A murine model of experimental allergic conjunctivitis (EAC) was induced in BALB/c, C57BL/6 or IL-27Rα-deficient (WSX-1-/- ) mice by short ragweed pollen, with untreated or PBS-treated mice as controls. The serum, eyeballs, conjunctiva, cervical lymph nodes (CLNs) were used for study. Gene expression was determined by RT-qPCR, and protein production and activation were evaluated by immunostaining, ELISA and Western blotting. RESULTS: Typical allergic manifestations and stimulated thymic stromal lymphopoietin (TSLP) signaling and Th2 responses were observed in ocular surface of EAC models in BALB/c and C57BL/6 mice. The decrease of IL-27 at mRNA (IL-27/EBI3) and protein levels were detected in serum, conjunctiva and CLN, as evaluated by RT-qPCR, immunofluorescent staining, ELISA and Western blotting. EAC induced in WSX-1-/- mice showed aggravated allergic signs with higher TSLP-driven Th2-dominant inflammation, accompanied by stimulated Th17 responses, including IL-17A, IL-17F, and transcription factor RORγt. In contrast, Th1 cytokine IFNγ and Treg marker IL-10, with their respective transcription factors T-bet and foxp3, were largely suppressed. Interestingly, imbalanced activation between reduced phosphor (P)-STAT1 and stimulated P-STAT6 were revealed in EAC, especially WSX-1-/- -EAC mice. CONCLUSION: These findings demonstrated a natural protective mechanism by IL-27, of which signaling deficiency develops a Th17-type hyperresponse that further aggravates Th2-dominant allergic inflammation.

Short-Term Effects of Overnight Orthokeratology on Corneal Sensitivity in Chinese Children and Adolescents.

PURPOSE: To assess the effects of the 3-month period of orthokeratology (OK) treatment on corneal sensitivity in Chinese children and adolescents. METHODS: Thirty subjects wore overnight OK lenses in both eyes for 3 months and were assessed at baseline, 1 day, 1 week, 1 month, and 3 months after the treatment. Changes in corneal sensitivity were measured by the Cochet-Bonnet (COBO) esthesiometer at the corneal apex and approximately 2 mm from the temporal limbus. Changes in refraction and corneal topography were also measured. RESULTS: Central corneal sensitivity suffered a significant reduction within the first month of the OK treatment period but returned to the baseline level at three months (F = 3.009, P=0.039), while no statistically significant difference occurred in temporal sensitivity (F = 2.462, P=0.074). The baseline of central corneal sensitivity correlated with age (r = -0.369, P=0.045). A marked change in refraction (uncorrected visual acuity, P < 0.001; spherical equivalent, P < 0.001) and corneal topographical condition (mean keratometry reading, P < 0.001; eccentricity value, P < 0.001; Surface Regularity Index, P < 0.001) occurred, but none of these measurements were correlated with corneal sensitivity. CONCLUSIONS: A 3-month period OK treatment causes a reduction in central corneal sensitivity in Chinese children and adolescents but with a final recovery to the baseline level, which might be because neuronal adaptation occurred earlier in children and adolescents than in adults.

Identification for Differential Localization of Putative Corneal Epithelial Stem Cells in Mouse and Human.

Human Corneal epithelial stem cells (CESCs) have been identified to reside in limbus for more than 2 decades. However, the precise location of CESCs in other mammalian remains elusive. This study was to identify differential localization of putative CESCs in mice. Through a series of murine corneal cross-sections from different directions, we identified that anatomically and morphologically the murine limbus is composed of the thinnest epithelium and the thinnest stroma without any palisades of Vogt-like niche structure. The cells expressing five of stem/progenitor cell markers are localized in basal layer of entire murine corneal epithelium. BrdU label-retaining cells, a key characteristic of epithelial stem cells, are detected in both limbal and central cornea of mouse eye. Functionally, corneal epithelium can be regenerated in cultures from central and limbal explants of murine cornea. Such a distribution of mouse CESCs is different from human cornea, where limbal stem cell concept has been well established and accepted. We are aware that some new evidence supports limbal stem cell concept in mouse recently. However, it is important to know that central cornea may provide an alternative source of stem cells when one utilizes mice as animal model for corneal research.