The Gly103Arg variant in hereditary transthyretin amyloidosis.

Background: Hereditary transthyretin amyloidosis (ATTRv) is an autosomal dominant inherited systematic disease primarily affecting the peripheral and autonomic nervous system, heart, eyes and kidney. Over 140 variants have been identified worldwide, with the Gly103Arg variant reported exclusively in China. This variant is characterized by early onset eye manifestations, making accurate and timely diagnosis difficult. Therefore, we conducted a case study and literature review to investigate the clinical characteristics of the Gly103Arg variant in hereditary transthyretin amyloidosis. Methods: We identified three patients and an asymptomatic carrier in a four-generation family by sequencing the TTR gene. The proband underwent a lumbar puncture, electromyography, abdominal fat biopsy, among other tests. Case reports of Gly103Arg variant were retrieved through a literature search for an analysis of clinical characteristics. Results: The study included clinical data of 44 patients. Our literature review collected data on 41 patients and the present report supplied 3 patients with the Gly103Arg variant. The mean age at onset was 39.1 ± 4.27 years (range 30-47 years) with a female ratio of 52.3%. All cases were reported in China, predominantly in southern regions, especially Yunan and Guizhou Provinces. The initial manifestation was blurred vision, except for one case presenting with numbness in the upper extremities. All of them had vitreous opacity; 17 cases had peripheral neuropathy,6 cases had autonomic neuropathy, and 3 cases had cardiopathy. No disease-related deaths have been reported to date. Conclusion: The Gly103Arg variant is unique to the Chinese population, frequently occurring in southern China. The main clinical manifestations are blurred vision, vitreous opacity, and neuropathy, with cardiopathy being rare. ATTRv should be considered if a patient diagnosed with CIDP does not respond to related therapy. Abdominal fat biopsy is a convenient and accurate diagnostic method.

Anterior Chamber Flare as a Non-Invasive Assessment of Intraocular Immune Status and Ocular Complications in Proliferative Diabetic Retinopathy.

Proliferative diabetic retinopathy (PDR) is a vision-threatening complication of diabetes mellitus (DM). Anterior chamber (AC) flare and intraocular cytokines are potent biomarkers reflecting the intraocular immune status in PDR. This study aimed to elucidate the complex interrelationship between AC flare and intraocular cytokines in PDR eyes. A retrospective observational study was conducted on 19 PDR eyes of 19 patients with type 2 DM, and on 19 eyes of 19 patients with idiopathic macular hole or epiretinal membrane as controls. AC flare was measured before pars plana vitrectomy (PPV). Aqueous humor (AH) and vitreous fluid (VF) samples were collected at the time of PPV, and the quantities of 27 cytokines in both intraocular fluids were analyzed. In the PDR and control groups, Spearman's rank correlation analysis revealed a positive correlation between AC flare and IL-8 level in both AH and VF. Additionally, IL-8 levels in AH correlated positively with IL-8 levels in VF. In the PDR group, receiver operating characteristic curve analysis identified IL-8 level in AH as a significant predictor for both diabetic macular edema (DME) and vitreous hemorrhage (VH) complications. The cut-off values of IL-8 were established at ≥26.6 pg/mL for DME and ≥7.96 pg/mL for VH. Given the positive correlation between AC flare and AH IL-8 level, the present findings suggest that AC flare value may potentially be a non-invasive biomarker for predicting DME.

Case report: Characterizing of free-floating pigmented vitreous cyst using swept-source optical coherence tomography.

Aim: A free-floating vitreous cyst is a rare eye disease. This study aimed to find diagnostic imaging methods and imaging features for vitreous cysts. Methods: This article presents a case report along with a literature review of published cases of vitreous cysts. The case report describes a highly myopic 60-year-old woman with a pigmented, free-floating vitreous cyst in her right eye. A search of the PubMed database using the keywords "vitreous cyst" was performed to identify other cases reported in the literature and to summarize the imaging methods used to diagnose and visualize vitreous cysts and the imaging features of vitreous cysts. Results: A thorough ophthalmic examination was performed in the present case, including slit-lamp photography, B-scan ultrasound, broad line fundus imaging, spectral-domain optical coherence tomography (SD-OCT), and ultra-wide field SS-OCT. The literature review revealed the imaging methods used in previously reported cases of vitreous cysts in which ultra-wide field SS-OCT has the advantages of wide scanning depth and high imaging clarity. Conclusion: SS-OCT has an advantage over SD-OCT in providing intuitive morphological characteristic images for the diagnosis of posterior vitreous cysts. The comprehensive assessment of multimodal imaging examinations, including SS-OCT, is of significant value for the diagnosis and differential diagnosis of vitreous cysts.

Synthetic vitreous fibers (SVFs): adverse outcome pathways (AOPs) and considerations for next generation new approach methods (NAMs).

Fiber dimension, durability/dissolution, and biopersistence are critical factors for the risk of fibrogenesis and carcinogenesis. In the modern era, to reduce, refine, and replace animals in toxicology research, the application of in vitro test methods is paramount for hazard evaluation and designing synthetic vitreous fibers (SVFs) for safe use. The objectives of this review are to: (1) summarize the international frameworks and acceptability criteria for implementation of new approach methods (NAMs), (2) evaluate the adverse outcome pathways (AOPs), key events (KEs), and key event relationships (KERs) for fiber-induced fibrogenesis and carcinogenesis in accordance with Organization for Economic Co-operation and Development (OECD) guidelines, (3) consider existing and emerging technologies for in silico and in vitro toxicity testing for the respiratory system and the ability to predict effects in vivo, (4) outline a recommended testing strategy for evaluating the hazard and safety of novel SVFs, and (5) reflect on methods needs for in vitro in vivo correlation (IVIVC) and predictive approaches for safety assessment of new SVFs. AOP frameworks following the conceptual model of the OECD were developed through an evaluation of available molecular and cellular initiating events, which lead to KEs and KERs in the development of fiber-induced fibrogenesis and carcinogenesis. AOP framework development included consideration of fiber physicochemical properties, respiratory deposition and clearance patterns, biosolubility, and biopersistence, as well as cellular, organ, and organism responses. Available data support that fiber AOPs begin with fiber physicochemical characteristics which influence fiber exposure and biosolubility and subsequent key initiating events are dependent on fiber biopersistence and reactivity. Key cellular events of pathogenic fibers include oxidative stress, chronic inflammation, and epithelial/fibroblast proliferation and differentiation, which ultimately lead to hyperplasia, metaplasia, and fibrosis/tumor formation. Available in vitro models (e.g. single-, multi-cellular, organ system) provide promising NAMs tools to evaluate these intermediate KEs. However, data on SVFs demonstrate that in vitro biosolubility is a reasonable predictor for downstream events of in vivo biopersistence and biological effects. In vitro SVF fiber dissolution rates >100 ng/cm2/hr (glass fibers in pH 7 and stone fibers in pH 4.5) and in vivo SVF fiber clearance half-life less than 40 or 50 days were not associated with fibrosis or tumors in animals. Long (fiber lengths >20 µm) biodurable and biopersistent fibers exceeding these fiber dissolution and clearance thresholds may pose a risk of fibrosis and cancer. In vitro fiber dissolution assays provide a promising avenue and potentially powerful tool to predict in vivo SVF fiber biopersistence, hazard, and health risk. NAMs for fibers (including SVFs) may involve a multi-factor in vitro approach leveraging in vitro dissolution data in complement with cellular- and tissue- based in vitro assays to predict health risk.

Multimodal imaging and histopathological evaluation in silicone oil keratopathy.

PURPOSE: To describe features in silicone oil keratopathy using multimodal imaging and histopathological examination. METHODS: Case report. RESULT: A 21-year-old male developed right corneal decompensation in the heavy SO (HSO)-filled eye. The patient underwent an initial lensectomy, pars plana vitrectomy (PPV) and HSO tamponade due open-globe injury with corneal wound, lens damage and in two retained intravitreal glass foreign bodies, followed by a revisional PPV with HSO tamponade due to tractional detachment associated with proliferative vitreoretinopathy and epiretinal membrane. One month after the removal of HSO, ophthalmic examination of the right eye showed corneal decompensation. The AS-OCT showed corneal thickening, intrastromal scattered hyperreflective dots and large rounded/oval hyporeflective space; the latter were suggestive of emulsified HSO microbubbles and larger bubbles, respectively. In vivo confocal microscopy showed multiple presumed SO-related corneal changes, including hyper-reflective fibrotic changes in the basal epithelium, reduced density ans altered morphology of keratocytes cell population, increased pleomorphism and polymegathism of the endothelium with reduced endothelial cell, and presence of inflammatory cells. The patient underwent a penetrating keratoplasty, pupilloplasty and retropupillary iris-claw IOL implantation. The histopathological examination of the host corneal button showed Descemet's membrane irregularity and thickened corneal stroma with focal intrastromal silicone oil vacuoles, surrounded by macrophages. CONCLUSION: We described for the first time intrastromal hyperreflective dots as a sign associated with SO-related keratopathy. Moreover, this case report supports the ability of emulsified SO to penetrate the cornea inducing a local low-grade chronic inflammation.

Impact of microorganism virulence on endophthalmitis outcomes.

AIMS: To determine the impact of microorganism virulence on visual outcomes in endophthalmitis. METHODS: Retrospective, multicentre cohort study of patients presenting with endophthalmitis between 2006 and 2021. A literature review was conducted to divide cultured microorganisms into low and high virulence subcategories. RESULTS: 610 eyes with endophthalmitis were recruited from New Zealand, the UK and Israel. The median age was 69.4 years. The median visual acuity was hand movements at presentation and 20/120 at the final follow-up. Severe visual loss (≤20/200) occurred in 237 eyes (38.9%) at the final follow-up. The culture-positive rate was 48.5% (296 eyes). Highly virulent microorganisms were associated with a 4.48 OR of severe visual loss at the final follow-up (p<0.001) and a 1.90 OR of developing retinal detachment or requiring enucleation or evisceration during the follow-up period (p=0.028). Oral flora were observed in 76 eyes (25.7%), and highly virulent microorganisms were observed in 68 eyes (22.9%). Highly virulent microorganisms were more likely to be found after glaucoma surgery (15 eyes, 34.9%) and vitrectomy (five eyes, 35.7%) compared with intravitreal injections (two eyes, 2.9%) and cataract surgery (22 eyes, 24.2%). On multivariate analysis, the following were associated with poorer visual outcomes: poor presenting vision (p<0.001), glaucoma surgery (p=0.050), trauma (p<0.001), oral microorganism (p=0.001) and highly virulent microorganism (p<0.001). CONCLUSION: This is the first classification of microorganisms into high and low virulence subcategories that demonstrate highly virulent microorganisms were associated with poor visual outcomes and increased likelihood of retinal detachment and enucleation.

Silencing the long noncoding RNA MALAT1 inhibits vitreous-induced epithelial-mesenchymal transition in RPE cells by regulating the PDGFRs/AKT axis.

PURPOSE: Epithelial-mesenchymal transition (EMT) is a crucial pathological process that contributes to proliferative vitreoretinopathy (PVR), and research indicates that factors present in the vitreous that target cells play pivotal roles in regulating EMT. Experimental studies have confirmed that rabbit vitreous (RV) promotes EMT in human retinal pigment epithelial (RPE) cells. The long noncoding RNA (lncRNA) MALAT1 has been implicated in EMT in various diseases. Thus, this study aimed to investigate the involvement of lncRNA MALAT1 in vitreous-induced EMT in RPE cells. METHODS: MALAT1 was knocked down in ARPE-19 cells by short hairpin RNA (shRNA) transfection. Reverse transcription PCR (RT‒PCR) was used to evaluate MALAT1 expression, and Western blotting analysis was used to measure the expression of EMT-related proteins. Wound-healing, Transwell, and cell contraction assays were conducted to assess cell migration, invasion, and contraction, respectively. Additionally, cell proliferation was assessed using the CCK-8 assay, and cytoskeletal changes were examined by immunofluorescence. RESULTS: MALAT1 expression was significantly increased in ARPE-19 cells cultured with RV. Silencing MALAT1 effectively suppressed EMT and downregulated the associated factors snail1 and E-cadherin. Furthermore, silencing MALAT1 inhibited the RV-induced migration, invasion, proliferation, and contraction of ARPE-19 cells. Silencing MALAT1 also decreased RV-induced AKT and P53 phosphorylation. CONCLUSIONS: In conclusion, lncRNA MALAT1 participates in regulating vitreous-induced EMT in human RPE cells; these results provide new insight into the pathogenesis of PVR and offer a potential direction for the development of antiproliferative drugs.

Vitreoschisis-induced vitreous cortex remnants in proliferative vitreoretinopathy: A comprehensive review from basic research to clinical practice.

Proliferative vitreoretinopathy (PVR) significantly impacts the prognosis of rhegmatogenous retinal detachment (RRD), one of the most critical and increasing causes of vision loss in the Western world. Despite advancements in surgical instruments and techniques, the failure rate due to PVR remains substantial, necessitating additional surgeries and often leading to unsatisfactory visual outcomes. This comprehensive review explores the role of vitreoschisis-induced vitreous cortex remnants (VCR) as a critical, previously under-recognised factor contributing to PVR. Vitreoschisis, a phenomenon where the inner lamellae of the posterior vitreous cortex detach while the outermost layers remain attached to the retina, creates VCR that may contain hyalocytes and serve as scaffolds for fibrocellular proliferation. These remnants are difficult to visualise without triamcinolone acetonide (TA) staining, leading to their frequent lack of recognition in clinical practice. Moreover, removing VCR can be challenging and time-consuming, often requiring meticulous surgical techniques to avoid retinal damage and ensure complete elimination. This review consolidates insights from basic research and clinical practice, emphasising the importance of complete vitreous removal and effective VCR detection and removal to mitigate PVR risks. It highlights the histopathological and clinical evidence supporting the hypothesis that VCR, containing hyalocytes, play a pivotal role in preretinal membrane formation. The review also discusses epidemiological data, surgical management strategies and potential future directions, including improved visualisation techniques and the development of new surgical tools and methods. This review aims to improve surgical outcomes and reduce the frequency and burden of RRD-related complications by addressing VCR as a critical factor in PVR.

Computer Modelling Study of Volume Kinetics in Intraocular Segments Following Airbag Impact Using Finite Element Analysis.

Background: We have previously studied the physiological and mechanical responses of the eye to blunt trauma in various situations using finite element analysis (FEA). In this study, we evaluated the volume kinetics of an airbag impact on the eye using FEA to sequentially determine the volume change rates of intraocular segments at various airbag deployment velocities. Methods: The human eye model we created was used in simulations with the FEA program PAM-GENERISTM (Nihon ESI, Tokyo, Japan). Different airbag deployment velocities, 30, 40, 50, 60 and 70 m/s, were applied in the forward direction. The volume of the deformed eye impacted by the airbag was calculated as the integrated value of all meshes in each segment, and the decrease rate was calculated as the ratio of the decreased volume of each segment at particular timepoints to the value before the airbag impact. Results: The minimum volume of the anterior chamber was 63%, 69% and 50% at 50, 60 and 70 m/s airbag impact velocity, respectively, showing a curve with a sharp decline followed by gradual recovery. In contrast to the anterior chamber, the volume of the lens recovered promptly, reaching 80-90% at the end of observation, except for the case of 60 m/s. Following the decrease, the volume increased to more than that of baseline at 60 m/s. The rate of volume change of the vitreous was distributed in a narrow range, 99.2-100.4%. Conclusion: In this study, we found a large, prolonged decrease of volume in the anterior chamber, a similar large decrease followed by prompt recovery of volume in the lens, and a time-lag in the volume decrease between these tissues. These novel findings may provide an important insight into the pathophysiological mechanism of airbag ocular injuries through this further evaluation, employing a refined FEA model representing cuboidal deformation, to develop a more safe airbag system.

Two cases of avulsed retinal vessel syndrome with different course.

Purpose: To report two cases of vitreous hemorrhage caused by avulsed retinal vessel syndrome (ARVS), one of which was successfully treated without vascular occlusion. Observations: A 62-year-old female presented with vitreous hemorrhage of unknown origin. We performed vitrectomy and found a detached and ruptured retinal vein below the optic nerve head. After coagulating the peripheral side of the blood vessel, we were able to prevent the recurrence of vitreous hemorrhage. However, she developed branch retinal vein occlusion and subsequently macular edema. In the other case, a 71-year-old woman also had vitreous hemorrhage, but the fundus was partially visible. The retinal vein in the superior nasal quadrant was detached from the retinal surface and bled into the vitreous cavity. We performed vitrectomy to relieve the vitreous traction. Although we did not coagulate the vein, there was no recurrence of vitreous hemorrhage after surgery. Conclusions and Importance: By releasing the vitreous traction with vitrectomy, we were able to treat the patient with ARVS without vascular occlusion.

Liquid Biopsy for Proliferative Diabetic Retinopathy: Single-Cell Transcriptomics of Human Vitreous Reveals Inflammatory T-Cell Signature.

Purpose: Current therapies for proliferative diabetic retinopathy (PDR) do not specifically target VEGF-independent, cell-type-specific processes that lead to vision loss, such as inflammatory pathways. This study aimed to identify targetable cell types and corresponding signaling pathways by elucidating the single-cell landscape of the vitreous of patients with PDR. Design: Case series. Subjects: Vitreous and peripheral blood obtained from 5 adult patients (6 eyes) undergoing pars plana vitrectomy for vision-threatening PDR. Methods: Single-cell RNA sequencing (scRNA-seq) was performed on vitreous cells obtained from diluted cassette washings during vitrectomy from 6 eyes and peripheral blood mononuclear cells (PBMCs, n = 5). Droplet-based scRNA-seq was performed using the Chromium 10x platform to obtain single-cell transcriptomes. Differences in tissue compartments were analyzed with gene ontology enrichment of differentially expressed genes and an unbiased ligand-receptor interaction analysis. Main Outcome Measures: Single-cell transcriptomic profiles of vitreous and peripheral blood. Results: Transcriptomes from 13 675 surgically harvested vitreous cells and 22 636 PBMCs were included. Clustering revealed 4 cell states consistently across all eyes with representative transcripts for T cells (CD2, CD3D, CD3E, and GZMA), B cells (CD79A, IGHM, MS4A1 (CD20), and HLA-DRA), myeloid cells (LYZ, CST3, AIF1, and IFI30), and neutrophils (BASP1, CXCR2, S100A8, and S100A9). Most vitreous cells were T cells (91.6%), unlike the peripheral blood (46.2%), whereas neutrophils in the vitreous were essentially absent. The full repertoire of adaptive T cells including CD4+, CD8+ and T regulatory cells (Treg) and innate immune system effectors (i.e., natural killer T cells) was present in the vitreous. Pathway analysis also demonstrated activation of CD4+ and CD8+ memory T cells and ligand-receptor interactions unique to the vitreous. Conclusions: In the first single-cell transcriptomic characterization of human vitreous in a disease state, we show PDR vitreous is primarily composed of T cells, a critical component of adaptive immunity, with activity and proportions distinct from T cells within the peripheral blood, and neutrophils are essentially absent. These results demonstrate the feasibility of liquid vitreous biopsies via collection of otherwise discarded, diluted cassette washings during vitrectomy to gain mechanistic and therapeutic insights into human vitreoretinal disease. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Vitreopapillary Findings in Non-Arteritic Ischemic Optic Neuropathy versus Healthy Eyes: A Clinical and OCT Comparison.

PURPOSE: To study the vitreopapillary interface in non-arteritic ischemic optic neuropathy (NAION) for features that may predispose to optic nerve perfusion defects. DESIGN: Case-control study. PARTICIPANTS AND CONTROLS: Patients with NAION (Study group) were compared with healthy non-NAION patients with crowded discs (Control group I) and non-crowded optic discs (Control group II). METHODS: The vitreopapillary interface was studied in 32 eyes with NAION using high-resolution OCT scans. Results were compared with two control groups consisting of age, sex, and refraction-matched non-NAION individuals with crowded optic discs (Control Group I: 31 eyes) and non-crowded optic discs (Control Group II: 32 eyes). MAIN OUTCOME MEASURES: The incidence of total posterior vitreous detachment (PVD), vitreopapillary and vitreovascular attachments, and epipapillary membranes. RESULTS: The rate of PVD over the macula was similar among groups (NAION: 62.5%, Control I: 61.3%, and Control II: 65.6%, p=0.93) while the posterior hyaloid remained attached to the crowded discs at a significantly higher rate (NAION: 81.2%, Control I: 83.9% and Control II: 43.7%, p=0.0005). A higher rate of focal vitreopapillary attachments on crowded discs than on non-crowded discs was noted (NAION: 72.2%, crowded control I: 58.7%, and non-crowded control II: 19.1%, p=0.007). Vitreovascular attachments (NAION: 69%, crowded control I: 3% vs non-crowded control II: 6%, p=0.00001) and dense epipapillary membranes were observed in NAION eyes. CONCLUSIONS: Crowded discs may have stronger vitreopapillary attachments. A close relationship of these attachments with optic nerve vessels may lead to the transmission of strong tractional forces by a syneretic vitreous gel, especially after macular PVD. This transduced mechanical force may contort the vessel wall and disrupt the blood flow in NAION.

Causal relationships between inflammatory cytokines and myopia: an analysis of genetic and observational studies.

Objective: This study aims to explore the causal relationship between inflammatory markers and myopia through the use of bidirectional Mendelian randomization (MR) and myopia animal models. Methods: The authors utilized data from a comprehensive and publicly accessible genome-wide association study (GWAS) for our analysis, which includes 460 536 European ancestry control subjects and 37 362 myopia patients. Utilizing a two-sample Mendelian randomization analysis framework, 27 inflammatory markers were investigated as exposure variables with myopia serving as the outcome variable. Nine MR analysis techniques were employed, with inverse-variance weighting (IVW) as the principal MR analysis method. Heterogeneity was assessed using Cochrane's Q test. The identification of single-nucleotide polymorphisms (SNPs) and outliers linked to myopia was achieved via MR-PRESSO. The expression of interleukin-2 (IL-2) in the vitreous of guinea pigs subjected to experimentally induced form-deprivation myopia (FDM) was examined. Results: Elevated concentrations of IL-2 and IL-2ra were found to be associated [IVW estimate odds ratio (OR): 1.003, 95% CI: 1.001-1.005, P=0.001] and strongly associated (IVW estimate OR: 1.002, 95% CI: 1.000-1.003, P=0.049) with an increased risk of myopia, respectively. Conversely, lower levels of C-reactive protein (CRP) (IVW estimate OR: 0.996, 95% CI: 0.994-0.999, P=0.002) and tumour necrosis factor alpha (IVW estimate OR: 0.995, 95% CI: 0.994-0.996, P<0.001) were robustly linked to a heightened risk of myopia. IL-2 expression was notably upregulated in the vitreous of guinea pigs with experimentally induced FDM. Conclusions: Elevated levels of inflammatory factors, especially IL-2 and IL-2ra, have a potential causal relationship with myopia susceptibility, providing new insights into the pathogenesis of myopia.

Examination of Vitreolenticular Interface in Relation to Different Phacoemulsification Parameters in Early and Late Postoperative Period.

Background: The surgical parameters of phacoemulsification can significantly impact the behavior of the anterior hyaloid membrane (AHM). Methods: In this prospective study, anterior segment optical coherence tomography was used to examine the attachment or detachment of the AHM of 82 eyes after uneventful phacoemulsification preoperatively and postoperatively over 1 year. The impacts of the capsulorhexis' size, number of hydrodissections, nuclear sclerosis grade, cumulative dissipated energy (CDE), ultrasonic time, total surgical time, weakness of zonular fibers, presence of lens materials in Berger's space (LM-BS), and fluid usage were investigated in relation to the behavior of the AHM. Results: A significant linear trend regarding anterior vitreous detachment (AVD) was observed in the presence of zonular weakness and high CDE at all postoperative times (p ≤ 0.024 and p ≤ 0.005, respectively). Similarly, AVD was observed at 1-month, 3-month, and 1-year follow-ups in cases of high nuclear sclerosis grades (p ≤ 0.044) and high fluid usage (p ≤ 0.021). A significant correlation was observed in the group of LM-BS as the zonular weakness value increased (OR: 0.085; 95% CI: 0.017 to 0.420; p = 0.002), and the fluid usage was also significantly higher (OR: 1.049; 95% CI: 1.003-1.096; p = 0.037). Conclusions: Zonular weakness, high CDE, a hard nucleus, and high fluid usage are risk factors for postoperative AVD.

Neurodegenerative biomarkers in different chambers of the eye relative to plasma: an agreement validation study.

BACKGROUND: Protein biomarkers have been broadly investigated in cerebrospinal fluid and blood for the detection of neurodegenerative diseases, yet a clinically useful diagnostic test to detect early, pre-symptomatic Alzheimer's disease (AD) remains elusive. We conducted this study to quantify Aß40, Aß42, total Tau (t-Tau), hyperphosphorylated Tau (ptau181), glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) in eye fluids relative to blood. METHODS: In this cross-sectional study we collected vitreous humor, aqueous humor, tear fluid and plasma in patients undergoing surgery for eye disease. All six biomarkers were quantitatively measured by digital immunoassay. Spearman and Bland-Altman correlation analyses were performed to assess the agreement of levels between ocular fluids and plasma. RESULTS: Seventy-nine adults underwent pars-plana vitrectomy in at least one eye. Of the 79, there were 77 vitreous, 67 blood, 56 tear fluid, and 51 aqueous samples. All six biomarkers were quantified in each bio-sample, except GFAP and NfL in tear fluid due to low sample volume. All six biomarkers were elevated in vitreous humor compared to plasma samples. T-Tau, ptau181, GFAP and NfL were higher in aqueous than in plasma, and t-Tau and ptau181 concentrations were higher in tear fluid than in plasma. Significant correlations were found between Aß40 in plasma and tears (r = 0.5; p = 0.019), t-Tau in plasma and vitreous (r = 0.4; p = 0.004), NfL in plasma and vitreous (r = 0.3; p = 0.006) and plasma and aqueous (r = 0.5; p = 0.004). No significant associations were found for Aß42, ptau181 and GFAP among ocular fluids relative to plasma. Bland-Altman analysis showed aqueous humor had the closest agreement to plasma across all biomarkers. Biomarker levels in ocular fluids revealed statistically significant associations between vitreous and aqueous for t-Tau (r = 0.5; p = 0.001), GFAP (r = 0.6; p < 0.001) and NfL (r = 0.7; p < 0.001). CONCLUSION: AD biomarkers are detectable in greater quantities in eye fluids than in plasma and show correlations with levels in plasma. Future studies are needed to assess the utility of ocular fluid biomarkers as diagnostic and prognostic markers for AD, especially in those at risk with eye disease.

Postmortem biochemistry of GFAP, NSE and S100B in cerebrospinal fluid and in vitreous humor for estimation of postmortem interval: a pilot study.

Postmortem interval (PMI) is a challenging issue in forensic practice. Although postmortem biomarkers of traumatic brain injury (TBI) are recognised as an emerging resource for PMI estimation, their role remains controversial. This study aims to evaluate postmortem concentrations of three TBI biomarkers (GFAP, NSE and S100B) in two matrices (cerebrospinal fluid and vitreous humor), in order to find out if these markers could be adopted in PMI estimation. Thirty-five deceased individuals with known PMI who underwent forensic autopsy at the University of Parma were examined. Matrices were collected during autopsy, then biomarker concentrations were determined through the enzyme-linked immunosorbent assay. Statistical significance of the data in relation to PMI was studied. The correlation of biomarkers with PMI, examined with samples divided into six groups according to the number of days elapsed since death, was not statistically significant, although S100B in cerebrospinal fluid showed an increasing trend in cases from 1 to 5 days of PMI. Comparison between cases with 1 day of PMI and those with 2 or more days of PMI showed a statistically significant correlation for GFAP and NSE in cerebrospinal fluid. GFAP and NSE in cerebrospinal fluid represent appropriate biomarkers in PMI estimation to distinguish cases with one day of PMI from those with two or more days of PMI. The current study was limited by the scarcity of the cohort and the narrow spectrum of cases. Further research is needed to confirm these observations.

In vitrothree-dimensional volumetric printing of vitreous body models using decellularized extracellular matrix bioink.

Hyalocytes, which are considered to originate from the monocyte/macrophage lineage, play active roles in vitreous collagen and hyaluronic acid synthesis. Obtaining a hyalocyte-compatible bioink during the 3D bioprinting of eye models is challenging. In this study, we investigated the suitability of a cartilage-decellularized extracellular matrix (dECM)-based bioink for printing a vitreous body model. Given that achieving a 3D structure and environment identical to those of the vitreous body necessitates good printability and biocompatibility, we examined the mechanical and biological properties of the developed dECM-based bioink. Furthermore, we proposed a 3D bioprinting strategy for volumetric vitreous body fabrication that supports cell viability, transparency, and self-sustainability. The construction of a 3D structure composed of bioink microfibers resulted in improved transparency and hyalocyte-like macrophage activity in volumetric vitreous mimetics, mimicking real vitreous bodies. The results indicate that our 3D structure could serve as a platform for drug testing in disease models and demonstrate that the proposed printing technology, utilizing a dECM-based bioink and volumetric vitreous body, has the potential to facilitate the development of advanced eye models for future studies on floater formation and visual disorders.

Case Reports of Severe Paediatric Sickle Cell Retinopathy: Disease Manifestations, Progression and Treatments.

Severe sickle retinopathy is commonly known in adults but not in children, hence any related treatment for sickle retinopathy in children was not well described. We reported 2 paediatric sickle patients (aged 12 and 13) presented with severe sickle retinopathy and described details of their disease progression and treatments over 2-3 years, along with the challenges faced when managing this particular group of young age sickle cell patients. Our case reports also demonstrated the benefits of laser photocoagulation treatment to early sickle proliferative disease, and how complications from advanced severe retinopathy hindered effective treatments.

Diabetic retinopathy from the vitreous proteome perspective: The INSC94Y transgenic pig model study.

INSC94Y transgenic pigs represent a model for mutant insulin gene-induced diabetes of youth, with impaired insulin secretion and beta cell loss, leading to elevated fasting blood glucose levels. A key complication of diabetes mellitus is diabetic retinopathy (DR), characterized by hyperglycemia-induced abnormalities in the retina. Adjacent to the retina lies the vitreous, a gelatinous matrix vital for ocular function. It harbors proteins and signaling molecules, offering insights into vitreous biology and ocular health. Moreover, as a reservoir for secreted molecules, the vitreous illuminates molecular processes within intraocular structures, especially under pathological conditions. To uncover the proteomic profile of porcine vitreous and explore its relevance to DR, we employed discovery proteomics to compare vitreous samples from INSC94Y transgenic pigs and wild-type controls. Our analysis identified 1404 proteins, with 266 showing differential abundance in INSC94Y vitreous. Notably, the abundances of ITGB1, COX2, and GRIFIN were significantly elevated in INSC94Y vitreous. Gene Set Enrichment Analysis unveiled heightened MYC and mTORC1 signaling in INSC94Y vitreous, shedding light on its biological significance in diabetes-associated ocular pathophysiology. These findings deepen our understanding of vitreous involvement in DR and provide valuable insights into potential therapeutic targets. Raw data are accessible via ProteomeXchange (PXD038198).