Role of hyperosmolarity in the pathogenesis and management of dry eye disease: proceedings of the OCEAN group meeting

A Comparative Study of Ocular Surface Disease in Childhood Glaucoma

PURPOSE

To evaluate ocular surface disease (OSD) in patients with childhood glaucoma (CG).

METHODS

A multicenter, comparative, cross-sectional study of 41 eyes of 27 patients with CG and 42 eyes of 42 healthy age- and sex-matched controls was conducted between 2021 and 2022. Developmentally delayed children and those having a coexisting systemic illness that might affect the ocular surface were not enrolled. Data collected included glaucoma type, glaucoma medications and surgeries, anterior segment examination, symptom frequency and severity, and tear break-up time (TBUT). Dry eye disease (DED) symptoms were evaluated using an Arabic-language SPEED questionnaire.

RESULTS

The average number of glaucoma medications and surgeries among the 27 patients with CG was 1.17 and 1.4, respectively. TBUT was shorter in patients with CG compared with controls and even shorter when glaucoma medication usage was accounted for. Punctate epithelial erosions were more prevalent in patients with CG and of a higher grade. The severity of all DED parameters, and the prevalence of all DED parameters except for eye fatigue, were greater in patients with CG on the day of questionnaire intake. In addition, each additional glaucoma drop was associated with worse TBUT and ocular surface dryness. All analyses mentioned above were statistically significant ( P < 0.05).

CONCLUSIONS

In this first study to comprehensively evaluate OSD in patients with CG, a significantly greater incidence of OSD signs and symptoms was found in patients with CG compared with a healthy population. Additional study by CG subtype is needed.

A Preservative-Free Combination of Sodium Hyaluronate and Trehalose Improves Dry Eye Signs and Symptoms and Increases Patient Satisfaction in Real-Life Settings: The TEARS Study

INTRODUCTION

Dry eye disease (DED) is a frequently observed condition characterized by ocular discomfort and visual disturbance. It is highly prevalent and impairs patients' quality of life (QoL). This study assessed the benefit of a preservative-free bioprotectant eye drop formulation containing sodium hyaluronate and trehalose (SH-trehalose) with regards to DED, as well as patient satisfaction, through a large-scale real-life survey.

METHODS

In a multi-center, international, prospective observational study, subjects with DED received SH-trehalose for 84 days. Ocular Surface Disease Index (OSDI), Dry Eye Questionnaire-5 items (DEQ-5), and patient satisfaction were assessed at baseline, day 28, and day 84, and clinical evaluations included ocular surface staining, Schirmer test, tear film break-up time (TBUT), and conjunctival hyperemia at baseline and day 84.

RESULTS

A total of 312 patients were evaluated, of whom 82.4% were women. The mean age was 57.9 ± 15.2 years. The mean OSDI score at baseline was 41.7 ± 20.6. After 84 days, the mean OSDI score was 27.3 ± 19.8 (p < 0.001). The percentage of patients with a severe OSDI score decreased from 60.3 to 34.5%. The DEQ-5 score significantly (p < 0.001) improved after 28 and 84 days, as did patient satisfaction. Ocular surface staining, Schirmer test, TBUT, and conjunctival hyperemia scores improved significantly (all p < 0.001) for both eyes with SH-trehalose between baseline and day 84. Tolerance of SH-trehalose was good.

CONCLUSIONS

SH-trehalose significantly improved the clinical signs and symptoms of DED after 84 days. Moreover, it significantly increased patient satisfaction and was well tolerated.

TRIAL REGISTRATION

NCT04803240.

Dry eye disease caused by viral infection: Past, present and future

Following viral infection, the innate immune system senses viral products, such as viral nucleic acids, to activate innate defence pathways, leading to inflammation and apoptosis, control of cell proliferation, and consequently, threat to the whole body. The ocular surface is exposed to the external environment and extremely vulnerable to viral infection. Several studies have revealed that viral infection can induce inflammation of the ocular surface and reduce tear secretion of the lacrimal gland (LG), consequently triggering ocular morphological and functional changes and resulting in dry eye disease (DED). Understanding the mechanisms of DED caused by viral infection and its potential therapeutic strategies are crucial for clinical interventional advances in DED. This review summarizes the roles of viral infection in the pathogenesis of DED, applicable diagnostic and therapeutic strategies, and potential regions of future studies.

Ophthalmic Formulations for the Treatment of Allergic Conjunctivitis and Their Effect on the Ocular Surface: A Review of Safety and Tolerability Assessments in Clinical Trials

Allergic conjunctivitis (AC) is the most common allergic eye disorder. Antiallergic eyedrops are the first line of pharmacological treatment. However, the application of antiallergic eyedrops can potentially alter tear homeostasis and affect the ocular surface, which may result in iatrogenic diseases such as dye eye disease (DED). Long-term treatment of AC with eyedrops containing preservatives and other components may increase the risk of DED and ocular surface damage. Here, we examined 20 clinical trials published during the past ten years with antihistamine ophthalmic formulations in the treatment of AC, to evaluate the extent of evidence about their safety and tolerability. Remarkably, we find that most trials lack an evaluation of the critical ocular surface parameters, such as tear film break-up time, tear volume, corneal and conjunctival damage, and inflammation, to properly assess the state of the ocular surface state after prolonged treatment. There is a need to increase awareness of the use of specific formulations that do not increase the risk of iatrogenic DED.

Perfluorohexyloctane ophthalmic solution for dry eye disease: pooled analysis of two phase 3 clinical trials

Background

Dry eye disease (DED) is commonly caused by excessive tear film evaporation due to Meibomian gland dysfunction (MGD). There is a need for DED treatment options that address tear evaporation and benefit patients across a broad range of demographic and disease characteristics. This study evaluated treatment effects of perfluorohexyloctane ophthalmic drop (formerly NOV03) in the pooled dataset from 2 pivotal clinical trials in patients with DED associated with MGD, both in the overall population and in patient subgroups based on sex, age, and baseline severity of eye dryness.

Methods

Pooled data from 2 similarly designed, phase 3, randomized controlled trials (GOBI, MOJAVE) were analyzed. Patients aged ≥18 years with DED administered perfluorohexyloctane (n=614) or hypotonic (0.6% solution) saline control (n=603) four times daily for 8 weeks. Primary endpoints were total corneal fluorescein staining (tCFS) score (National Eye Institute scale, 0-15) and eye dryness visual analog scale (VAS) score (0-100). Efficacy was evaluated using analysis of covariance among patient subgroups (male and female, older [≥65 years] and younger [18 to <65 years], tCFS score <7 and ≥7, VAS eye dryness score <70 and ≥70, MGD score <7 and ≥7, Schirmer I test <10 mm and ≥10 mm).

Results

Reductions in tCFS and VAS eye dryness scores were greater for perfluorohexyloctane versus control. In the overall patient population, least-squares mean treatment difference was -1.1 (95% CI: -1.41 to -0.79; p<0.0001) for tCFS and -9.0 (95% CI: -11.90 to -6.00; p<0.0001) for VAS eye dryness. Treatment favored perfluorohexyloctane over control in all patient subgroup analyses of tCFS and VAS eye dryness. Overall, the most common adverse event with perfluorohexyloctane was blurred vision (2.1% of patients), which was mild and transient.

Conclusions

Compared with a hypotonic saline control, perfluorohexyloctane improved both the signs and symptoms of DED, including in patients with greater self-reported severity of eye dryness.

Clinical trial registration

This study represents an integrated analysis of 2 previous clinical trials: GOBI (ClinicalTrials.gov, NCT04139798) and MOJAVE (ClinicalTrials.gov, NCT04567329).

Genomics of Staphylococcus aureus and Enterococcus faecalis isolated from the ocular surface of dry eye disease sufferers

Ocular surface inflammatory disorders, such as dry eye, are becoming increasingly prevalent. Developing new treatment strategies targeting harmful bacteria could provide significant therapeutic benefits. The purpose of this study was to characterize the common ocular pathogen Staphylococcus aureus and the rarer endophthalmitis-associated species Enterococcus faecalis isolated from the ocular surface of dry eye disease patients in Norway. Together the 7 isolates (5 S. aureus and 2 E. faecalis) comprise the complete set of members of each species isolated in our previous study of the ocular microbiome of 61 dry eye sufferers. We aimed to investigate the pathogenic potential of these isolates in relation to ocular surface health. To this end, we used whole genome sequencing, multiplex PCR directed at virulence genes and antibiotic susceptibility tests encompassing clinically relevant agents. The E. faecalis isolates showed resistance to only gentamicin. S. aureus isolates displayed susceptibility to most of the tested antibiotics, except for two isolates which showed resistance to trimethoprim/sulfamethoxazole and three isolates which were resistant to ampicillin. Susceptibilities included sensitivity to several first-line antibiotics for treatment of ocular infections by these species. Thus, treatment options would be available if required. However, spontaneous resistance development to gentamicin and rifampicin occurred in some S. aureus which could be a cause for concern. Whole genome sequencing of the isolates showed genome sizes ranging from 2.74 to 2.83 Mbp for S. aureus and 2.86 Mbp for E. faecalis, which is typical for these species. Multilocus sequence typing and phylogenetic comparisons with previously published genomes, did not suggest the presence of eye-specific clusters for either species. Genomic analysis indicated a high probability of pathogenicity among all isolates included in the study. Resistome analysis revealed the presence of the beta-lactamase blaZ gene in all S. aureus isolates and the dfrG gene in two of them; while E. faecalis isolates carried the lsa(A) gene which confers intrinsic resistance to lincosamides and streptogramin A in this species. Screening for virulence factors revealed the presence of various pathogenicity associated genes in both S. aureus and E. faecalis isolates. These included genes coding for toxin production and factors associated with evading the host immune system. Some of the identified genes (tst, hylA & hylB) are suggested to be linked to the pathophysiology of dry eye disease. Lastly, the presence of specific S. aureus virulence genes was confirmed through multiplex PCR analysis.

Multidimensional immunotherapy for dry eye disease: current status and future directions

Dry Eye Disease (DED) is a multifactorial condition driven by tear film hyperosmolarity, immune dysregulation, and neuro-immune interactions. The immune system plays a central role in its pathogenesis, influencing both inflammation and ocular surface damage. While traditional immunotherapies like anti-inflammatory agents and immunosuppressants offer symptom relief, their long-term use is limited by side effects. This review focuses on emerging immunotherapies, including biologics, stem cell therapy, gene therapy, nanotechnology, and exosome-based treatments, all of which hold promise in modulating immune responses and promoting tissue repair. The relationship between the ocular microbiome and DED is also explored, with an emphasis on personalized immunotherapy. Key challenges for future research include identifying novel therapeutic targets, optimizing clinical translation, and evaluating the long-term efficacy of these innovative treatments.

Advancements in Ocular Therapy: A Review of Emerging Drug Delivery Approaches and Pharmaceutical Technologies

Eye disorders affect a substantial portion of the global population, yet the availability of efficacious ophthalmic drug products remains limited. This can be partly ascribed to a number of factors: (1) inadequate understanding of physiological barriers, treatment strategies, drug and polymer properties, and delivery systems; (2) challenges in effectively delivering drugs to the anterior and posterior segments of the eye due to anatomical and physiological constraints; and (3) manufacturing and regulatory hurdles in ocular drug product development. The present review discusses innovative ocular delivery and treatments, encompassing implants, liposomes, nanoparticles, nanomicelles, microparticles, iontophoresis, in situ gels, contact lenses, microneedles, hydrogels, bispecific antibodies, and gene delivery strategies. Furthermore, this review also introduces advanced manufacturing technologies such as 3D printing and hot-melt extrusion (HME), aimed at improving bioavailability, reducing therapeutic dosages and side effects, facilitating the design of personalized ophthalmic dosage forms, as well as enhancing patient compliance. This comprehensive review lastly offers insights into digital healthcare, market trends, and industry and regulatory perspectives pertaining to ocular product development.

Enhancing the hypotensive effect of latanoprost by combining synthetic phosphatidylcholine liposomes with hyaluronic acid and osmoprotective agents

The first line of glaucoma treatment focuses on reducing intraocular pressure (IOP) through the prescription of topical prostaglandin analogues, such as latanoprost (LAT). Topical ophthalmic medicines have low bioavailability due to their rapid elimination from the ocular surface. Nanotechnology offers innovative ways of enhancing the ocular bioavailability of antiglaucoma agents while reducing administration frequency. This study aims to combine LAT-loaded synthetic phosphatidylcholine liposomes with hyaluronic acid (0.2% w/v) and the osmoprotectants betaine (0.40% w/v) and leucine (0.90% w/v) (LAT-HA-LIP) to extend the hypotensive effect of LAT while protecting the ocular surface. LAT-HA-LIP was prepared as a mixture of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphocholine, cholesterol and α-tocopherol acetate. LAT-HA-LIP exhibited high drug-loading capacity (104.52 ± 4.10%), unimodal vesicle sizes (195.14 ± 14.34 nm) and a zeta potential of -13.96 ± 0.78 mV. LAT-HA-LIP was isotonic (284.00 ± 1.41 mOsm L-1), had neutral pH (7.63 ± 0.01) and had suitable surface tension (44.07 ± 2.70 mN m-1) and viscosity (2.69 ± 0.15 mPa s-1) for topical ophthalmic administration. LAT-HA-LIP exhibited optimal in vitro tolerance in human corneal and conjunctival epithelial cells. No signs of ocular alteration or discomfort were observed when LAT-HA-LIP was instilled in albino male New Zealand rabbits. Hypotensive studies revealed that, after a single eye drop, the effect of LAT-HA-LIP lasted 24 h longer than that of a marketed formulation and that relative ocular bioavailability was almost three times higher (p < 0.001). These findings indicate the potential ocular protection and hypotensive effect LAT-HA-LIP offers in glaucoma treatment.

Pharmacogenomic Analysis of Response to Topical Tumor Necrosis Factor α Antagonist Licaminlimab (OCS-02) in Dry Eye Disease [RETRACTED]

PURPOSE

The purpose of this study was to evaluate the pharmacogenomics of response to topical ocular tumor necrosis factor α (TNFα) inhibitor licaminlimab in patients with DED.

METHODS

Three single-nucleotide polymorphisms (SNPs) associated with Sjögren syndrome, 3 in the TNFα gene and 1 in the TNF receptor 1 (TNFR1) gene, were assessed for association with response to licaminlimab in participants from a randomized, vehicle-controlled, Phase 2 study in which adults with DED and severe ocular discomfort persisting despite treatment with artificial tears received licaminlimab or vehicle for 6 weeks. Response was assessed for change from baseline in Global Ocular Discomfort score at Day 29 of treatment. The pharmacogenomic analysis was a prospectively specified exploratory objective of the study. mRNA expression for TNFα, interleukin (IL) 1β, and IL8 in conjunctival epithelium cells was determined. The relationship between SNPs and response to licaminlimab was assessed using a mixed model repeated measures analysis.

RESULTS

SNP rs1800693 in the TNFR1 gene showed a significant effect on response to licaminlimab ( P < 0.0001, initial association test); no effect was seen for any of the other SNPs tested. The CC genotype of rs1800693 was associated with much greater response to licaminlimab than the CT or TT genotypes: LS mean changes from baseline to Day 29 in Global Ocular Discomfort score were -29.5, -0.09, and -3.90, in patients with the CC, CT, and TT genotypes, respectively ( P < 0.0001). No significant effect was observed in vehicle-treated patients. Improvements from baseline were seen in 3/4 licaminlimab-treated participants with the CC genotype. Conjunctival epithelium cell levels of mRNA for TNFα, IL1β, and IL8 decreased from baseline in participants with the CC genotype, but not with the CT or TT genotypes. Between-genotype differences in mRNA levels were not observed in participants receiving vehicle.

CONCLUSIONS

The CC genotype of rs1800693, relatively common in patients with DED, was strongly associated with response to licaminlimab and decreased inflammatory cytokine gene expression in ocular surface cells during treatment. This study is one of the first to our knowledge to investigate pharmacogenomics in the treatment of DED.

Preservatives and ocular surface disease: A review

Ocular surface disease (OSD) is a complex condition that can cause a range of symptoms (e.g, dryness, irritation, and pain) and can significantly impact the quality of life of affected individuals. Iatrogenic OSD, a common finding in patients with glaucoma who receive chronic therapy with topical ocular antihypertensive drugs containing preservatives such as benzalkonium chloride (BAK), has been linked to damage to the ocular surface barrier, corneal epithelial cells, nerves, conjunctival goblet cells, and trabecular meshwork. Chronic BAK exposure activates inflammatory pathways and worsens symptoms, compromising the success of subsequent filtration surgery in an exposure-dependent manner. In eyes being treated for glaucoma, symptomatic treatment of OSD may provide some relief, but addressing the root cause of the OSD often necessitates reducing or, ideally, eliminating BAK toxicity. Strategies to decrease BAK exposure in patients with glaucoma encompass the use of preservative-free formulations or drugs with alternative and less toxic preservatives such as SofZia®, Polyquad, potassium sorbate, or Purite®. Though the benefits of these alternative preservatives are largely unproven, they might be considered when financial constraints prevent the use of preservative-free versions. For patients receiving multiple topical preserved drugs, the best practice is to switch to nonpreserved equivalents wherever feasible, regardless of OSD severity. Furthermore, nonpharmacological approaches, including laser or incisional procedures, should be considered. This review explores the effects of BAK on the ocular surface and reviews strategies for minimizing or eliminating BAK exposure in patients with glaucoma in order to significantly improve their quality of life and prevent complications associated with chronic exposure to BAK.

Expert Consensus Recommendations for the Management of Ocular Surface Inflammation in Patients With Glaucoma

PRCIS

We have developed through a consensus process 24 clinical recommendations for the comprehensive management of ocular surface inflammation in glaucoma patients, including diagnostic criteria, prevention measures, and treatment strategies according to ocular surface disease severity.

PURPOSE

To obtain expert consensus on the diagnosis, prevention, and management of ocular surface inflammation (OSI) in patients with glaucoma.

METHODS

An international steering committee of glaucoma and/or ocular surface disease (OSD) experts and a wider faculty of members from the Educational Club of Ocular Surface and Glaucoma (ECOS-G) collaborated to develop clinical recommendations on best practice in the management of OSI in glaucoma patients using a nonanonymous interactive quasi-Delphi process. Clinical recommendations were formulated by the steering committee based on an analysis of the recent literature to determine unmet needs, together with a web-based interactive survey of faculty members' opinion in seven identified areas of OSI management in glaucoma. Topics included (1) diagnosis of OSD, (2) diagnosis of OSI, (3) causes of OSI, (4) impact of OSD/OSI, (5) prevention of OSI, (6) treatment of OSI, and (7) inflammation and the deep structures of the eye. Faculty members were invited to vote on the clinical recommendations, and the steering committee then determined whether consensus had been achieved.

RESULTS

Consensus was obtained on 24 clinical recommendations by 80%-100% of faculty members. There was consensus that OSI should be investigated in all glaucoma patients. The main prevention measure in glaucoma patients with pre-existing OSD was the elimination/minimisation of preserved medications, especially BAK-preserved eye drops. A subtractive treatment strategy rather than an additive strategy is recommended according to OSI/OSD severity to improve the ocular health and/or before glaucoma surgery.

CONCLUSION

These recommendations for the management of OSI in glaucoma should be useful to guide decision-making in clinical practice.

The Mid-Term Effect of Preservative-Free Artificial Tears Containing Hyaluronic Acid on Dry Eye Incidence after Cataract Surgery: A Retrospective Cohort Study

The aim of this study is to survey the effectiveness of preservative-free artificial tears containing hyaluronic acid (HA) on post-cataract surgery dry eye disease (DED) prevention. A retrospective cohort study was performed, and patients that received cataract surgeries were divided into either an HA group or non-HA group depending on the artificial tear they used. A total of 37 and 74 eyes were enrolled into the HA and non-HA groups, respectively, after the selection. The primary outcomes are postoperative superficial keratitis and multiple (>3) DED symptoms. The generalized linear model was utilized to calculate the adjusted odds ratio (aOR) and 95% confidence interval (CI) of primary outcomes between the two groups. There were 10 and 2 episodes of superficial keratitis in the non-HA group and HA group, respectively, and the HA group demonstrated a significantly lower incidence of superficial keratitis (p < 0.001). Moreover, 13 and 5 patients developed multiple DED symptoms in the non-HA and HA groups, and the HA group illustrated fewer multiple DED symptoms (p = 0.024). The lower preoperative tear break-up time (TBUT) was correlated with superficial keratitis in the HA group (p = 0.043), while old age, low preoperative TBUT and ocular surface staining were associated with superficial keratitis in the non-HA group (all p < 0.05). Lower preoperative TBUT was correlated with multiple DED symptoms in the HA group (p = 0.020), while female sex, low preoperative TBUT and any DED symptoms were associated with multiple DED symptoms in the non-HA group (all p < 0.05). In conclusion, the usage of preservative-free artificial tears containing HA is associated with lower postoperative DED events.

Astaxanthin activated the SLC7A11/GPX4 pathway to inhibit ferroptosis and enhance autophagy, ameliorating dry eye disease

Dry eye disease (DED) is a common eye disease in clinical practice. The crucial pathogenesis of DED is that hyperosmolarity activates oxidative stress signaling pathways in corneal epithelial and immune cells and, thus, produces inflammatory molecules. The complex pathological changes in the dry eye still need to be elucidated to facilitate treatment. In this study, we found that astaxanthin (AST) can protect against DED through the SLC7A11/GPX4 pathway. After treatment with AST, the SLC7A11/GPX4 pathway was positively activated in DED both in vivo and in vitro, accompanied by enhanced autophagy and decreased ferroptosis. In hyperosmolarity-induced DED corneal epithelial cells, AST increased the expression of ferritin to promote iron storage and reduce Fe2+ overload. It increased glutathione (GSH) and GPX4, scavenged reactive oxygen species (ROS) and lipid peroxide, and rescued the mitochondrial structure to prevent ferroptosis. Furthermore, inhibition of ferroptosis by ferrostatin-1 (Fer-1), iron chelator deferoxamine mesylate (DFO), or AST could activate healthy autophagic flux. In addition, in a dry eye mouse model, AST upregulated SLC7A11 and GPX4 and inhibited ferroptosis. To summarize, we found that AST can ameliorate DED by reinforcing the SLC7A11/GPX4 pathway, which mainly affects oxidative stress, autophagy, and ferroptosis processes.

The Usage of Different Hyaluronic-Acid-Containing Artificial Tears and the Treatment Outcome of Intense Pulsed Light Therapy for Dry Eye Disease: A Retrospective Cohort Study

In this study, we aimed to investigate the effect of different hyaluronic acid (HA)-containing artificial tears on dry eye disease (DED) treatment in combination with intense pulsed light (IPL) therapy. A retrospective cohort study was conducted, and the participants received IPL therapy and HA-containing artificial tears. There were 42 and 40 eyes in the 0.10% and 0.15% HA groups after selection, respectively. The main outcomes were the postoperative non-invasive tear break-up time (NITBUT), Schirmer II test results, ocular surface stain, and numbers of DED-related symptoms. A generalized linear model was utilized to produce the adjusted odds ratio (aOR) and 95% confidence interval (CI) of the main outcomes between groups. At the three-month follow-up, the NITBUT was significantly higher in the 0.15% HA group (p = 0.023), and the NITBUT recovery was also significantly better in the 0.15% HA group compared to the 0.10% HA group (p = 0.039). The multiple DED-related symptoms significantly correlated with no DED symptom improvement in both the 0.10% and 0.15% HA groups (both p < 0.05), while the low pre-treatment NITBUT was marginally related to no DED symptom improvement in the 0.10% HA group (p = 0.047). A low NITBUT and Schirmer II test result correlated with no DED symptom improvement in both the groups (all p < 0.05). In conclusion, the application of 0.10% and 0.15% HA-containing artificial tears revealed similar effects to IPL therapy for DED.

Modified Sodium hyaluronate conjugated to riboflavin (Har® 0.1 %) as lubricant eyedrops in the treatment of dry eye: A prospective randomised study

Background

This study evaluates the therapeutic efficacy of HAr® (a novel ophthalmic solution containing modified hyaluronic acid covalently linked to riboflavin) compared to hyaluronic acid eye drops in patients with dry eye disease (DED).

Methods

Sixteen consecutive patients with bilateral medium to severe DED were divided into two groups. Group 1 received HAr® 0.1 % (Ribohyal®), while Group 2 received HA 0.1 % eye drops. Parameters such as Ocular Surface Disease Index (OSDI) score, osmolarity, break-up time (BUT), non-invasive BUT (NIBUT), tear meniscus measurement, Schirmer test, and Oxford Staining were evaluated. This study has been successfully registered on ClinicalTrials.gov public (Identifier NCT06122428).

Results

The Ribohyal group showed faster improvement in OSDI scores, with a statistically significant difference at 2 h (mean classification difference: -51.75; p = 0.0003). Photophobia significantly reduced at 2 h, 4 weeks, and 8 weeks in the Ribohyal group compared to baseline (p < 0.0001). Osmolarity improved significantly after 8 weeks in both groups (p < 0.0001).

Conclusions

HAr® 0.1 % (Ribohyal®) effectively reduced DED symptoms and improved photophobia within 2 h of instillation, lasting up to 8 weeks.

Complement Component C5a and Fungal Pathogen Induce Diverse Responses through Crosstalk between Transient Receptor Potential Channel (TRPs) Subtypes in Human Conjunctival Epithelial Cells

The conjunctiva has immune-responsive properties to protect the eye from infections. Its innate immune system reacts against external pathogens, such as fungi. The complement factor C5a is an important contributor to the initial immune response. It is known that activation of transient-receptor-potential-vanilloid 1 (TRPV1) and TRP-melastatin 8 (TRPM8) channels is involved in different immune reactions and inflammation in the human body. The aim of this study was to determine if C5a and mucor racemosus e voluminae cellulae (MR) modulate Ca2+-signaling through changes in TRPs activity in human conjunctival epithelial cells (HCjECs). Furthermore, crosstalk was examined between C5a and MR in mediating calcium regulation. Intracellular Ca2+-concentration ([Ca2+]i) was measured by fluorescence calcium imaging, and whole-cell currents were recorded using the planar-patch-clamp technique. MR was used as a purified extract. Application of C5a (0.05-50 ng/mL) increased both [Ca2+]i and whole-cell currents, which were suppressed by either the TRPV1-blocker AMG 9810 or the TRPM8-blocker AMTB (both 20 µM). The N-terminal peptide C5L2p (20-50 ng/mL) blocked rises in [Ca2+]i induced by C5a. Moreover, the MR-induced rise in Ca2+-influx was suppressed by AMG 9810 and AMTB, as well as 0.05 ng/mL C5a. In conclusion, crosstalk between C5a and MR controls human conjunctival cell function through modulating interactions between TRPV1 and TRPM8 channel activity.

Cornea-SELEX for aptamers targeting the surface of eyes and liposomal drug delivery

Cornea is the major barrier to drug delivery to the eye, which results in low bioavailability and poor efficacy of topical eye treatment. In this work, we first select cornea-binding aptamers using tissue-SELEX on pig cornea. The top two abundant aptamers, Cornea-S1 and Cornea-S2, could bind to pig cornea, and their K d values to human corneal epithelial cells (HCECs) were 361 and 174 nм, respectively. Aptamer-functionalized liposomes loaded with cyclosporine A (CsA) were developed as a treatment for dry eye diseases. The K d of Cornea-S1- or Cornea-S2-functionalized liposomes reduces to 1.2 and 15.1 nм, respectively, due to polyvalent binding. In HCECs, Cornea-S1 or Cornea-S2 enhanced liposome uptake within 15 min and extended retention to 24 h. Aptamer CsA liposomes achieved similar anti-inflammatory and tight junction modulation effects with ten times less CsA than a free drug. In a rabbit dry eye disease model, Cornea-S1 CsA liposomes demonstrated equivalence in sustaining corneal integrity and tear break-up time when compared to commercial CsA eye drops while utilizing a lower dosage of CsA. The aptamers obtained from cornea-SELEX can serve as a general ligand for ocular drug delivery, suggesting a promising avenue for the treatment of various eye diseases and even other diseases.

Impact of Topical 0.05% Cyclosporine A Eye Drops on Post-Femtosecond-Assisted Laser In Situ Keratomileusis Ocular Surface Recovery: A Randomized Clinical Trial

OBJECTIVES

To investigate the effect of topical 0.05% cyclosporine A (CsA) eye drops as an adjunct to conventional therapy in maintaining post-femtosecond-assisted laser in situ keratomileusis (FS-LASIK) ocular surface stability.

METHODS

Sixty-six patients (eyes) undergoing FS-LASIK were randomized into 2 groups: 33 patients (eyes) in group I (conventional treatment group) and 33 patients (eyes) in group II (CsA group). Conventional treatments include topical levofloxacin, fluorometholone, and artificial tears. Group II received topical 0.05% CsA eye drops twice daily for three months in addition to conventional treatment. Ocular Surface Disease Index (OSDI), numerical rating scale (NRS), tear break-up time (TBUT), Schirmer I test (SIt), corneal fluorescein staining (CFS), conjunctival lissamine green (LG) staining, corneal sensitivity, and corneal nerve morphology were measured. In addition, tear inflammatory cytokine levels were measured using the Luminex assay. Follow-up was performed preoperatively and 1 and 3 months postoperatively.

RESULTS

In the CsA group, OSDI, TBUT, LG, corneal sensitivity, and corneal nerve fiber total branch density recovered better than in the conventional treatment group. As for tear inflammatory cytokines, interferon (INF) -γ, interleukin (IL)-10, and IL-6 levels were significantly higher in the conventional treatment group as compared with the CsA group. In addition, no significant differences in NRS, SIt, and CFS scores were observed between the two groups.

CONCLUSION

In conclusion, 0.05% CsA eye drops is a useful adjunct to conventional treatment for restoring the ocular surface stability after corneal refractive surgery and is more potent in sustaining anti-inflammatory effects.

Exploring the Link between Sleep Disorders and Ocular Health: A Comprehensive Clinical Study

Background

Sleep disorders and ocular conditions are prevalent health concerns with significant impact on the quality of life. However, the relationship between them remains underexplored. Additionally, therapeutic interventions targeting both sleep and eye health are explored.

Materials and Methods

A prospective clinical study was conducted involving 500 participants aged between 30 and 65 years, recruited from an outpatient clinic specializing in sleep disorders and ophthalmology. Participants underwent comprehensive assessments including polysomnography for sleep disorders diagnosis and ophthalmic examinations for ocular condition evaluation. Sleep quality was assessed using standardized questionnaires, while ocular health was evaluated through clinical examination, including measurements of intraocular pressure, tear film break-up time, and retinal imaging. Statistical analyses were performed using Chi-square tests and logistic regression models to determine associations between sleep disorders and ocular conditions, adjusting for potential confounders.

Results

Among the participants, 35% were diagnosed with sleep apnea, 25% with insomnia, 20% with dry eye syndrome, 15% with glaucoma, and 10% with diabetic retinopathy. Significant associations were found between sleep disorders and ocular conditions. Participants with sleep apnea were more likely to have dry eye syndrome (odds ratio [OR] = 2.5, 95% confidence interval [CI] = 1.8-3.4, P < 0.001) and glaucoma (OR = 1.8, 95% CI = 1.3-2.5, P = 0.002). Similarly, insomnia was associated with dry eye syndrome (OR = 2.2, 95% CI = 1.5-3.1, P < 0.001) and diabetic retinopathy (OR = 1.6, 95% CI = 1.1-2.3, P = 0.012).

Conclusion

This study highlights the significant association between sleep disorders and ocular conditions, suggesting a potential bidirectional relationship.

Discovery and Verification of Sjögren's Syndrome Protein Biomarkers in Tears by Targeted LC-MRM

Sjögren's syndrome (SS) is an autoimmune rheumatic disorder characterized by exocrine gland dysfunction, mainly from the lacrimal and salivary glands. The disease causes severe aqueous dry eye syndrome (DED) and is associated with high rates of complications, including corneal ulceration, scaring, and perforation. Systemic complications may occur as well as a higher risk of developing lymphoma. Diagnosis of SS-DED is often delayed and difficult to establish. With the aim of discovering biomarkers to help discriminate SS-DED patients, a combination of untargeted and targeted LC-MS/MS analyses were performed on tear samples collected on Schirmer strips and subjected to tryptic digestion. Following the analysis of three cohorts and the development of two targeted LC-sMRM methods for the verification of putative biomarkers found in the first cohort of samples, 64 proteins could be linked to Sjögren's syndrome, in the hopes of helping to confirm diagnoses as well as potentially stratifying the severity of disease in these patients. Proteins that were increased in SS-DED showed activation of the immune system and alterations in homeostasis. Several proteases and protease inhibitors were found to be significantly changing in SS-DED, as well as a consistent decrease in specific proteins known to be secreted by the lacrimal gland.

The new preservative-free ophthalmic formulation of bilastine 0.6% preserves the ocular surface epithelial integrity in a comparative in vitro study

Allergic conjunctivitis (AC) is the most common form of allergic eye disease and an increasingly prevalent condition. Topical eye drop treatments are the usual approach for managing AC, although their impact on the ocular surface is not frequently investigated. The aim of this study was to perform a comparative physicochemical characterization, and in vitro biological evaluations in primary conjunctival and corneal epithelial cells of the new multidose preservative-free bilastine 0.6% and main commercially available eye drops. MTT assay was used to measure cell viability; oxidative stress was analyzed with a ROS-sensitive probe; and apoptosis was evaluated monitoring caspase 3/7 activation. Differences in pH value, osmolarity, viscosity and phosphate levels were identified. Among all formulations, bilastine exhibited pH, osmolarity and viscosity values closer to tear film (7.4, 300 mOsm/l and ~ 1.5-10 mPa·s, respectively), and was the only phosphates-free solution. Single-dose ketotifen did not induce ROS production, and single-dose azelastine and bilastine only induced a mild increase. Bilastine and single-dose ketotifen and azelastine showed high survival rates attributable to the absence of preservative in its formulation, not inducing caspase-3/7-mediated apoptosis after 24 h. Our findings support the use of the new bilastine 0.6% for treating patients with AC to preserve and maintain the integrity of the ocular surface.

Ectoine protects corneal epithelial survival and barrier from hyperosmotic stress by promoting anti-inflammatory cytokine IL-37

PURPOSE

To explore novel role and molecular mechanism of a natural osmoprotectant ectoine in protecting corneal epithelial cell survival and barrier from hyperosmotic stress.

METHODS

Primary human corneal epithelial cells (HCECs) were established from donor limbus. The confluent cultures in isosmolar medium were switched to hyperosmotic media (400-500 mOsM), with or without ectoine or rhIL-37 for different time periods. Cell viability and proliferation were evaluated by MTT or WST assay. The integrity of barrier proteins and the expression of cytokines and cathepsin S were evaluated by RT-qPCR, ELISA, and immunostaining with confocal microscopy.

RESULTS

HCECs survived well in 450mOsM but partially damaged in 500mOsM medium. Ectoine well protected HCEC survival and proliferation at 500mOsM. The integrity of epithelial barrier was significantly disrupted in HCECs exposed to 450mOsM, as shown by 2D and 3D confocal immunofluorescent images of tight junction proteins ZO-1 and occludin. Ectoine at 5-20 mM well protected these barrier proteins under hyperosmotic stress. The expression of TNF-α, IL-1β, IL-6 and IL-8 were dramatically stimulated by hyperosmolarity but significantly suppressed by Ectoine at 5-40 mM. Cathepsin S, which was stimulated by hyperosmolarity, directly disrupted epithelial barrier. Interestingly, anti-inflammatory cytokine IL-37 was suppressed by hyperosmolarity, but restored by ectoine at mRNA and protein levels. Furthermore, rhIL-37 suppressed cathepsin S and rescued cell survival and barrier in HCECs exposed to hyperosmolarity.

CONCLUSION

Our findings demonstrate that ectoine protects HCEC survival and barrier from hyperosmotic stress by promoting IL-37. This provides new insight into pathogenesis and therapeutic potential for dry eye disease.

Efficacy of meibomian gland expression combined with Home-Based therapy in the management of dry eye Disease: A systematic review and Meta-Analysis

PURPOSE

To compare the effectiveness of meibomian gland expression (MGX) combined with home-based therapy versus home-based therapy alone for the treatment of dry eye disease (DED) caused by meibomian gland dysfunction (MGD).

METHODS

A systematic review of randomized controlled studies (RCTs), reporting the effects of MGX combined with home-based therapy in 2 databases, PubMed and Web of Science, was performed according to the PRISMA statement. The search period was until August 20, 2023. According to the heterogeneity, a random or fixed effects model was performed in the meta-analysis. The standardized mean difference (SMD) was calculated to analyze dry eye symptoms (DES) score, tear film break-up time (TBUT), total corneal fluorescein staining (tCFS) and meibomian glands expressibility (MGE). All analyses were performed by RevMan Web, version 5.7. The Cochrane risk of bias tool was used to analyze the quality of the studies selected.

RESULTS

Two RCTs with a total of 99 patients were included. The studies reported that MGX combined with home-based therapy improves DES score, TBUT, tCFS and MGE compared to the home-based therapy. However, the meta-analysis indicated that MGX combined with home-based therapy only seems to be beneficial in reducing DES score (SMD -0.49; 95 % CI: -0.89 to -0.08; P = 0.02; I2 = 0 %). In addition, although TBUT, tCFS and MGE reported a slight trend in favor of MGX combined with home-based therapy, it was non-significant.

CONCLUSIONS

While MGX combined with home-based therapy seem to show some evidence of alleviating dry eye symptoms, there is insufficient evidence to conclude the effects of this treatment definitively particularly in improving dry eye signs caused by MGD, such as TBUT, tCFS and MGE. Therefore, further RCTs are needed to elucidate these results.

New Korean Guidelines for the Diagnosis and Management of Dry Eye Disease

New Korean guidelines for the diagnosis and management of dry eye disease were developed based on literature reviews by the Korean Dry Eye Guideline Establishment Committee, a previous dry eye guideline by Korean Corneal Disease Study Group, a survey of Korean Dry Eye Society (KDES) members, and KDES consensus meetings. The new definition of dry eye was also proposed by KDES regular members. The new definition by the regular members of the KDES is as follows: "Dry eye is a disease of the ocular surface characterized by tear film abnormalities and ocular symptoms." The combination of ocular symptoms and an unstable tear film (tear breakup time <7 seconds) was considered as essential components for the diagnosis of dry eye. Schirmer test and ocular surface staining were considered adjunctive diagnostic criteria. The treatment guidelines consisted of a simplified stepwise approach according to aqueous deficiency dominant, evaporation dominant, and altered tear distribution subtypes. New Korean guidelines can be used as a simple, valid, and accessible tool for the diagnosis and management of dry eye disease in clinical practice.

How does ocular graft-versus-host disease fit under the dry eye umbrella? A review

Graft-versus-host disease (GVHD) is a systemic disease that can affect multiple organs as a consequence of an allogeneic haematopoietic stem cell transplant. One organ system that is often affected in GVHD is the eyes. Ocular GVHD (oGVHD) may involve various structures within the eye including the lacrimal glands, eyelids, conjunctiva, cornea, and nasolacrimal ducts, and is a source of morbidity in patients with GVHD. Common presenting features of GVHD overlap with dry eye disease (DED), including decreased tear production, epithelial disruption, and Meibomian gland dysfunction (MGD). In this review, we aim to compare oGVHD and DED to better understand the similarities and differences between the conditions, with a focus on pathophysiology, risk factors, clinical features, and treatments.

Potential Benefits of Integrin αvβ3 Antagonists in a Mouse Model of Experimental Dry Eye

PURPOSE

The purpose of this study was to extensively evaluate the efficacy of integrin αvβ3 antagonists for the treatment of experimental dry eye (EDE).

METHODS

Vitronectin, an αvβ3 ligand, was used to induce tumor necrosis factor-α gene expression in human THP-1 macrophages. To induce EDE, C57BL/6 mice were housed in a low-humidity controlled environment chamber and injected subcutaneously with scopolamine for 7 days. Subsequently, αvβ3 antagonists, including RGDfD, c(RGDfD), c(RGDiD), c(RGDfK), ATN-161, SB273005, and cilengitide, were administered topically to EDE animals under controlled environment chamber conditions. Corneal epithelial damage in EDE was assessed by fluorescein staining. The density of conjunctival goblet cells and secretion of tears was measured by period acid-Schiff staining and phenol red-impregnated cotton threads, respectively. Inflammation markers, including tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-17A, and metalloproteinase (MMP)-9, in the pooled cornea and conjunctiva tissues were examined by real-time polymerase chain reaction.

RESULTS

The inhibitory effects of αvβ3 antagonists on the vitronectin-induced tumor necrosis factor-α gene expression and integrin-mediated inflammatory signaling were validated in THP-1 macrophages. αvβ3 antagonists ameliorated the impairment of the corneal epithelial barrier with varying therapeutic efficacies, compared with vehicle-treated mice. c(RGDfD) and c(RGDiD) significantly protected against goblet cell loss, tear reduction, and proinflammatory gene expression in EDE.

CONCLUSIONS

Topical applications of αvβ3 antagonists yield therapeutic benefits in EDE by promoting corneal epithelial defect healing and reducing inflammation. Antagonistic targeting αvβ3 may be a novel promising strategy to treat patients with dry eye disease.

Ectoine, from a Natural Bacteria Protectant to a New Treatment of Dry Eye Disease

Ectoine, a novel natural osmoprotectant, protects bacteria living in extreme environments. This study aimed to explore the therapeutic effect of ectoine for dry eye disease. An experimental dry eye model was created in C57BL/6 mice exposed to desiccating stress (DS) with untreated mice as controls (UT). DS mice were dosed topically with 0.5-2.0% of ectoine or a vehicle control. Corneal epithelial defects were detected via corneal smoothness and Oregon Green dextran (OGD) fluorescent staining. Pro-inflammatory cytokines and chemokines were evaluated using RT-qPCR and immunofluorescent staining. Compared with UT mice, corneal epithelial defects were observed as corneal smoothness irregularities and strong punctate OGD fluorescent staining in DS mice with vehicle. Ectoine treatment protected DS mice from corneal damage in a concentration-dependent manner, and ectoine at 1.0 and 2.0% significantly restored the corneal smoothness and reduced OGD staining to near normal levels. Expression of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) and chemokines CCL3 and CXCL11 was significantly elevated in the corneas and conjunctivas of DS mice, whereas 1.0 and 2.0% ectoine suppressed these inflammatory mediators to near normal levels. Our findings demonstrate that ectoine can significantly reduce the hallmark pathologies associated with dry eye and may be a promising candidate for treating human disease.

Efficacy and Safety of Quantum Molecular Resonance Electrotherapy in Patients with Aqueous-Deficient, Evaporative and Mixed-Type Dry Eye: A Randomized Interventional Study

INTRODUCTION

To evaluate the efficacy and safety of Quantum Molecular Resonance (QMR) treatment in patients with severe dry eye disease (DED), as well as its effects on aqueous-deficient (ADDE), evaporative (EDE), and mixed (MDE) dry eye.

METHODS

In this prospective, interventional study, 81 patients were randomly allocated to received four treatment sessions of QMR at 1-week intervals (Rexon-Eye®, Resono Ophthalmic, Trieste, Italy) (QRM group) or tear substitute four times daily, containing 0.15% sodium hyaluronate and 3% trehalose (Thealoz Duo®, Thea Pharma, France) (SH-TH group). Outcome measures included ocular surface disease index (OSDI) questionnaire, tear meniscus height (TMH), tear breakup time (TBUT), non-invasive breakup time (NIBUT), corneal fluorescein staining (CFS), lipid layer thickness (LLT), tear film osmolarity (OSM), and meibomian gland dysfunction (MGD) grade, which were assessed at baseline and 1-month and 3-month follow-up.

RESULTS

The QMR group achieved better improvements than the SH-TH group in OSDI and SANDE questionnaires, NIBUT, LLT, and CFS. The mean differences between the groups were as follows: OSDI (- 12.4 ± 0.25 points, P = 0.01), SANDE (10.6 ± 1.7 points, P = 0.01), NIBUT (2 ± 0.25 s, P = 0.01), LLT (18.7 ± 0.7 nm, P = 0.01), and CFS (1.2 ± 0.1 points, P = 0.02). In subgroups analysis, QMR treatment demonstrated a beneficial role to improve DED symptoms and signs in ADDE, EDE, and MDE.

CONCLUSION

QMR is an effective and well-tolerated treatment that seems to improve DED symptoms and signs in patients with severe DED. However, further studies are needed to confirm this.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT06119386.

Puerarin alleviates hyperosmotic stress-induced oxidative stress, inflammation, apoptosis and barrier damage of human corneal epithelial cells by targeting SIRT1/NLRP3 signaling

The increase of tear osmolarity caused by excessive evaporation of tear phase is the main pathological mechanism of dry eye disease (DED). Puerarin, the major bioactive ingredient isolated from the root of the Pueraria lobata (Willd.) Ohwi, has been reported to improve ophthalmic diseases in clinic. However, the effect and the potential regulatory mechanism related to silent information regulator sirtuin 1 (SIRT1)/NOD-like receptor family pyrin domain containing 3 (NLRP3) signaling of puerarin in DED has not been evaluated. In this study, we aimed to explore the effect and mechanism of hyperosmotic stress (Hyp)-induced human corneal epithelial cell line (HCE-2). The viability of HCE-2 cells induced by Hyp with or without puerarin treatment was assessed by a CCK-8 assay. Results indicated that puerarin treatment enhanced cell viability, reduced reactive oxygen species (ROS) content, increased CAT and SOD activities, and elevated the ratio of GSH/GSSG in HCE-2 cells exposed to Hyp. Besides, TNF-α, IL-1β and IL-6 contents were decreased by puerarin. Additionally, puerarin inhibited Hyp-induced apoptosis and barrier disruption of HCE-2 cells. Moreover, molecular docking method suggested that puerarin bound to SIRT1, and upregulated SIRT1 and downregulated NLRP3 inflammasome proteins after puerarin treatment was observed. Furthermore, SIRT1 silencing alleviated the protective effects of puerarin on Hyp-induced HCE-2 cell damage. Collectively, puerarin attenuates Hyp-induced injury of HCE-2 cells by targeting regulating SIRT1/NLRP3 signaling.

A tissue-adhesive F127 hydrogel delivers antioxidative copper-selenide nanoparticles for the treatment of dry eye disease

Dry eye disease (DED) is currently the most prevalent condition seen in ophthalmology outpatient clinics, representing a significant public health issue. The onset and progression of DED are closely associated with oxidative stress-induced inflammation and damage. To address this, an aldehyde-functionalized F127 (AF127) hydrogel eye drop delivering multifunctional antioxidant Cu2-xSe nanoparticles (Cu2-xSe NPs) was designed. The research findings revealed that the Cu2-xSe nanoparticles exhibit unexpected capabilities in acting as superoxide dismutase and glutathione peroxidase. Additionally, Cu2-xSe NPs possess remarkable efficacy in scavenging reactive oxygen species (ROS) and mitigating oxidative damage. Cu2-xSe NPs displayed promising therapeutic effects in a mouse model of dry eye. Detailed investigation revealed that the nanoparticles exert antioxidant, anti-apoptotic, and inflammation-mitigating effects by modulating the NRF2 and p38 MAPK signalling pathways. The AF127 hydrogel eye drops exhibit good adherence to the ocular surface through the formation of Schiff-base bonds. These findings suggest that incorporating antioxidant Cu2-xSe nanoparticles into a tissue-adhesive hydrogel could present a highly effective therapeutic strategy for treating dry eye disease and other disorders associated with reactive oxygen species. STATEMENT OF SIGNIFICANCE: A new formulation for therapeutic eye drops to be used in the treatment of dry eye disease (DED) was developed. The formulation combines copper-selenium nanoparticles (Cu2-xSe NPs) with aldehyde-functionalized Pluronic F127 (AF127). This is the first study to directly examine the effects of Cu2-xSe NPs in ophthalmology. The NPs exhibited antioxidant capabilities and enzyme-like properties. They effectively eliminated reactive oxygen species (ROS) and inhibited apoptosis through the NRF2 and p38 MAPK signalling pathways. Additionally, the AF127 hydrogel enhanced tissue adhesion by forming Schiff-base links. In mouse model of DED, the Cu2-xSe NPs@AF127 eye drops demonstrated remarkable efficacy in alleviating symptoms of DED. These findings indicate the potential of Cu2-xSe NPs as a readily available and user-friendly medication for the management of DED.

Comparative Analysis of the Osmoprotective Effects of Daily Disposable Contact Lens Packaging Solutions on Human Corneal Epithelial Cells

Purpose

Contact lens (CL) wear challenges the balance of the ocular surface environment by increasing water evaporation and tear osmolarity. Maintaining ocular surface homeostasis during CL wear remains a goal of lens manufacturers and an important consideration for eye care professionals. The purpose of this study was to measure the metabolic activity and inflammatory responses of a transformed human corneal epithelial cell (THCEpiC) line under hyperosmotic conditions in the presence of CL packaging solutions.

Methods

CL packaging solutions sampled from seven daily disposable silicone hydrogel CL blister packages were prepared at 25% and made hyperosmolar (400 mOsm/kg) with NaCl. THCEpiCs were incubated with each solution for 24 hr, after which cell culture supernatants were collected. THCEpiC metabolic activity was determined by an alamarBlue assay. Concentrations in cell culture supernatants of inflammatory cytokine (interleukin [IL]-6) and chemokine (IL-8), as well as monocyte chemoattractant protein-1 (MCP-1), were quantitated by specific enzyme-linked immunosorbent assays.

Results

THCEpiC metabolic activity under hyperosmolar conditions decreased in the presence of somofilcon A and senofilcon A solutions (p=0.04 and 0.004, respectively), but no other solution (all p≥0.09). Concentrations of IL-6 increased in the presence of delefilcon A, somofilcon A, narafilcon A, and senofilcon A solutions (all p≤0.001), but no other solution (all p≥0.08), while those of IL-8 increased in the presence of all solutions (all p≤0.03) but kalifilcon A (p>0.99), and those of MCP-1 increased in the presence of delefilcon A, verofilcon A, somofilcon A, and stenfilcon A solutions (all p<0.0001), but no other solution (all p>0.99).

Conclusion

CL packaging solutions differ in their capacity to inhibit epithelial inflammation. THCEpiC inflammatory response was less in the presence of a CL packaging solution containing osmoprotectants than in solutions lacking osmoprotectants under moderately hyperosmolar conditions in vitro. Clinical studies are warranted to further substantiate the benefit of osmoprotectants.

[The place of ciclosporin A cationic emulsion 0.1% in the therapy of xerophthalmia]

Dry eye disease (DED) is pathogenetically based on inflammation of the ocular surface. A step-by-step approach to DED treatment involves early initiation of anti-inflammatory therapy, including instillation of cyclosporine A (CsA). However, recommendations for the use of topical CsA in clinical practice are limited. This article presents an expert consensus on practical recommendations for the management of patients with DED, including indications, time of initiation and duration of CsA therapy, comparison of CsA forms currently registered in the Russian Federation, as well as issues of patient education.

Neurogenic dry eye associated with intravitreal injection of anti-VEGF agents

PURPOSE

To report a case of neurogenic dry eye (NDE) that developed after intravitreal ranibizumab injection (IVR).

CASE REPORT

A 71-year-old woman had a history of cataract phacoemulsification and intraocular lens (IOL) implantation, Nd:YAG laser posterior capsulotomy and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). Aneurysmal dilatation of the inferior temporal retina was found in the left fundus, which was diagnosed as retinal aneurysm, and intravitreal ranibizumab injection was administered. Dry eye was found in the left eye after the first injection. After the second injection, the patient developed severe dry eye with left eye dryness, photophobia, irritation, and blurred vision. The tear film breakup time (TBUT) value was 3 s, the Schirmer test value was 2 mm/5 min, corneal fluorescein staining (CFS) showed diffuse patellar staining of the corneal epithelium with a staining area of >50% and irregular staining at the edge of the corneal flap, and the corneal touch threshold value in the filament length was 1.5 cm in the left eye.

CONCLUSIONS

Patients with a history of intraocular lens implantation, Nd:YAG laser posterior capsulotomy, and femtosecond laser-assisted laser in situ keratomileusis surgery may have increased drug permeability due to an increased concentration of anti-VEGF drugs in the aqueous layer and thinning of the stromal layer of the cornea. The corneal subepithelial nerve repair mechanism was destroyed, causing neurogenic dry eye.

Current Advances in Regenerative Strategies for Dry Eye Diseases: A Comprehensive Review

Dry eye disease (DED) is an emerging health issue affecting millions of individuals annually. Ocular surface disorders, such as DED, are characterized by inflammation triggered by various factors. This condition can lead to tear deficiencies, resulting in the desiccation of the ocular surface, corneal ulceration/perforation, increased susceptibility to infections, and a higher risk of severe visual impairment and blindness. Currently, the clinical management of DED primarily relies on supportive and palliative measures, including the frequent and lifelong use of different lubricating agents. While some advancements like punctal plugs, non-steroidal anti-inflammatory drugs, and salivary gland autografts have been attempted, they have shown limited effectiveness. Recently, there have been promising developments in the treatment of DED, including biomaterials such as nano-systems, hydrogels, and contact lenses for drug delivery, cell-based therapies, biological approaches, and tissue-based regenerative therapy. This article specifically explores the different strategies reported so far for treating DED. The aim is to discuss their potential as long-term cures for DED while also considering the factors that limit their feasibility and effectiveness. These advancements offer hope for more effective and sustainable treatment options in the future.

Comparison of matrix metallopeptidase-9 expression following cyclosporine and diquafosol treatment in dry eye

PURPOSE

We sought to evaluate the expression of matrix metalloproteinase-9 (MMP-9) in dry eyes treated with 0.05% cyclosporin A and 3.0% diquafosol tetrasodium.

METHODS

One-hundred ninety-five eyes of 195 patients with dry eye were divided into three groups as follows: group 1, cyclosporin group (n = 69); group 2, diquafosol group (n = 59); and group 3, artificial tears eyes (n = 67). All eyes were treated and followed up for three months. Schirmer I Test, corneal staining, tear-film break-up time (TBUT), and tear-film MMP-9 content were measured at three months and compared between groups. The expression of MMP-9 was confirmed using a point-of-care test device (InflammaDry®; RPS Diagnostics, Sarasota, FL, USA) and graded as zero to four points.

RESULTS

At the third month, MMP-9 expression was lower in group 1 as compared with in groups 2 and 3 (p = 0.020 and 0.006, respectively). The mean MMP-9 grade according to point-of-care testing was also lower in group 1 than in groups 2 or 3 (p = 0.002 and 0.038, respectively). MMP-9 showed a correlation with corneal staining in both groups 1 and 2 (all p < 0.001) and with Schirmer I Test and TBUT in group 1 (p = 0.018 and 0.015, respectively).

CONCLUSIONS

MMP-9 expression and grade were lower after treatment with cyclosporin than after treatment with diquafosol in the dry eye disease. Anti-inflammatory treatment can decrease ocular MMP-9 levels in dry eye disease.

The Molecular Mechanisms Responsible for Tear Hyperosmolarity-Induced Pathological Changes in the Eyes of Dry Eye Disease Patients

Dry eye disease (DED) is a multifactorial disorder of the lacrimal system and ocular surface, characterized by a deficiency in the quality and/or quantity of the tear fluid. The multifactorial nature of DED encompasses a number of interconnected underlying pathologies, including loss of homeostasis, instability and hyperosmolarity of the tears, and the induction and propagation of detrimental inflammatory responses in the eyes, which finally results in the development of neurosensory dysfunction and visual disruption. Dryness, grittiness, scratchiness, discomfort, inflammation, burning, watering, ocular fatigue, pain, and decreased functional visual acuity are common symptoms of DED. Eye dysfunction drastically attenuates patients' quality of life. Accordingly, a better understanding of the pathogenic processes that regulate the development and progression of DED is crucially important for the establishment of new and more effective DED-related treatment approaches, which would significantly improve the quality of life of DED patients. Since the process of osmoregulation, which guards the ocular surface epithelia and maintains normal vision, is affected when the osmolarity of the tears is greater than that of the epithelial cells, tear hyperosmolarity (THO) is considered an initial, important step in the development, progression, and aggravation of DED. In order to delineate the role of THO in the pathogenesis of DED, in this review article, we summarize current knowledge related to the molecular mechanisms responsible for the development of THO-induced pathological changes in the eyes of DED patients, and we briefly discuss the therapeutic potential of hypo-osmotic eye drops in DED treatment.

Oxidative stress in the eye and its role in the pathophysiology of ocular diseases

Oxidative stress occurs through an imbalance between the generation of reactive oxygen species (ROS) and the antioxidant defense mechanisms of cells. The eye is particularly exposed to oxidative stress because of its permanent exposure to light and due to several structures having high metabolic activities. The anterior part of the eye is highly exposed to ultraviolet (UV) radiation and possesses a complex antioxidant defense system to protect the retina from UV radiation. The posterior part of the eye exhibits high metabolic rates and oxygen consumption leading subsequently to a high production rate of ROS. Furthermore, inflammation, aging, genetic factors, and environmental pollution, are all elements promoting ROS generation and impairing antioxidant defense mechanisms and thereby representing risk factors leading to oxidative stress. An abnormal redox status was shown to be involved in the pathophysiology of various ocular diseases in the anterior and posterior segment of the eye. In this review, we aim to summarize the mechanisms of oxidative stress in ocular diseases to provide an updated understanding on the pathogenesis of common diseases affecting the ocular surface, the lens, the retina, and the optic nerve. Moreover, we discuss potential therapeutic approaches aimed at reducing oxidative stress in this context.

The Efficacy and Safety of Rebamipide Ophthalmic Suspension (OPC-12759) in Patients with Dry Eye Disease: A Systematic Review of Randomized Controlled Trials

The aim of this paper is to evaluate the efficacy and safety of Rebamipide (REB) ophthalmic suspension in dry eye disease (DED). A systematic review that only included full-length randomized controlled studies (RCTs) reporting the effects of REB ophthalmic suspension in three databases, PubMed, Scopus and Web of Science, was performed according to the PRISMA statement. The Cochrane risk of bias tool was used to analyze the quality of the studies selected. A total of seven studies were included in this systematic review. Although the overall risk of bias was low, most studies were sponsored by the manufacturer. REB ophthalmic suspension treatment achieved higher improvement than the control group in all reported variables. The mean differences between both groups were in favor of the REB group and were as follows: dry eye-related quality of life score (DEQS) -3.5 ± 2.9 points, tear film break-up time (TBUT) of 0.7 ± 0.6 s, Schirmer test (ST) without anesthesia of 0.3 ± 0.6 mm and total corneal fluorescein staining (tCFS) of -1.2 ± 0.7 points. Adverse events (AEs) were 5.2 ± 7.6% superior in the REB group, with an overall compliance > 95%. Therefore, REB ophthalmic suspension is a safe and effective treatment that could be recommended in patients with DED.

Estrogen plays an important role by influencing the NLRP3 inflammasome

The nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is an important part of the natural immune system that plays an important role in many diseases. Estrogen is a sex hormone that plays an important role in controlling reproduction and regulates many physiological and pathological processes. Recent studies have indicated that estrogen is associated with disease progression. Estrogen can ameliorate some diseases (e. g, sepsis, mood disturbances, cerebral ischemia, some hepatopathy, Parkinson's disease, amyotrophic lateral sclerosis, inflammatory bowel disease, spinal cord injury, multiple sclerosis, myocardial ischemia/reperfusion injury, osteoarthritis, and renal fibrosis) by inhibiting the NLRP3 inflammasome. Estrogen can also promote the development of diseases (e.g., ovarian endometriosis, dry eye disease, and systemic lupus erythematosus) by upregulating the NLRP3 inflammasome. In addition, estrogen has a dual effect on the development of cancers and asthma. However, the mechanism of these effects is not summarized. This article reviewed the progress in understanding the effects of estrogen on the NLRP3 inflammasome and its mechanisms in recent years to provide a theoretical basis for an in-depth study.

New developments in the management of persistent corneal epithelial defects

A persistent epithelial defect (PED) is a corneal epithelial defect that failed to heal after 2weeks. It is a condition that carries much morbidity, and our understanding of PED remains poor, with current treatment methods often having unsatisfactory outcomes. With PEDs becoming more prevalent, more efforts are required to establish reliable treatment modalities. Our reviews describe the causes of PEDs and the different approaches developed to manage them, as well as their associated limitations. Emphasis is placed on understanding various advances in the development of new treatment modalities. We have also described a case of a woman with a background of graft-versus-host disease on long-term topical corticosteroids who developed complicated PED involving both eyes. The current approach to managing PEDs generally involves exclusion of an active infection, followed by treatment modalities that aim to encourage corneal epithelial healing. Success rates, however, remain far from desirable, as treatment remains challenging due to multiple underlying etiologies. In summary, advances in the development of new therapies may be able to facilitate progress in the understanding and treatment of PED.

Exploring Signs and Symptoms Associated with Meibomian Gland Dysfunction for Use as Clinical Trial Endpoints

Purpose: Dry eye disease is attributed to impaired tear production and/or evaporative dry eye. Evaporative dry eye is frequently associated with meibomian gland dysfunction (MGD). The objective of this study was to identify clinical study endpoints related to MGD. Methods: This 22-day, noninterventional, case-control clinical study involved three cohorts with increasing MGD severity: no MGD, mild/moderate MGD, and severe MGD. Symptoms were assessed with an ocular symptom questionnaire grading blurred vision, eye burning, eye dryness, eye pain, light sensitivity, eye itching, eye foreign body sensation, and overall ocular discomfort. Sign assessments included the maximum meibum quality score (MMQS), tear breakup time, Schirmer tear tests, biomicroscopy, and corneal staining. Signs and symptoms were compared between cohorts and study visits. Results: Seventy-five study participants were assigned to the cohorts (25 per cohort). MMQS scores increased with increasing MGD severity, reflecting the selection criteria for the cohorts. Between-visit scores showed a weighted kappa statistic of 0.72 indicating substantial agreement. Mean scores of all assessed symptoms increased with increasing MGD severity. Scores for symptoms showed moderate (κ = 0.41-0.60) to substantial (κ = 0.61-0.80) agreement between visits. Overall ocular discomfort demonstrated the strongest correlation with the MMQS. Conclusion: The MMQS was a reproducible sign of MGD showing good agreement with ocular symptoms. Overall ocular discomfort was well correlated with typical dry eye symptoms and could potentially be used as a single measure of MGD symptoms. The findings from this observational study may inform endpoints for future clinical trials. ClinicalTrials.gov NCT01979887.

Diabetes-Associated Hyperglycemia Causes Rapid-Onset Ocular Surface Damage

Purpose

The metabolic alterations due to chronic hyperglycemia are well-known to cause diabetes-associated complications. Short-term hyperglycemia has also been shown to cause many acute changes, including hemodynamic alterations and osmotic, oxidative, and inflammatory stress. The present study was designed to investigate whether diabetes-associated hyperglycemia can cause rapid-onset detrimental effects on the tear film, goblet cells, and glycocalyx and can lead to activation of an inflammatory cascade or cellular stress response in the cornea.

Methods

Mouse models of type 1 and type 2 diabetes were used. Tear film volume, goblet cell number, and corneal glycocalyx area were measured on days 7, 14, and 28 after the onset of hyperglycemia. Transcriptome analysis was performed to quantify changes in 248 transcripts of genes involved in inflammatory, apoptotic, and stress response pathways.

Results

Our data demonstrate that type 1 and type 2 diabetes-associated hyperglycemia caused a significant decrease in the tear film volume, goblet cell number, and corneal glycocalyx area. The decrease in tear film and goblet cell number was noted as early as 7 days after onset of hyperglycemia. The severity of ocular surface injury was significantly more in type 1 compared to type 2 diabetes. Diabetes mellitus also caused an increase in transcripts of genes involved in the inflammatory, apoptotic, and cellular stress response pathways.

Conclusions

The results of the present study demonstrate that diabetes-associated hyperglycemia causes rapid-onset damage to the ocular surface. Thus, short-term hyperglycemia in patients with diabetes mellitus may also play an important role in causing ocular surface injury and dry eye.

Ciclosporin A Cationic Emulsion 0.1% for the Management of Dry Eye Disease: Facts That Matter for Eye-Care Providers

Dry eye disease (DED) is a chronic inflammatory disease of the ocular surface requiring long-term therapy. Severe forms of DED generally do not respond to tear substitutes alone or combined, and often require treatment with topical anti-inflammatory agents to break the vicious circle of inflammation. This review summarises data from randomised controlled trials and real-world evidence on the efficacy and safety of ciclosporin A 0.1% cationic emulsion (Ikervis®) for the management of DED. Improvements in clinical signs and symptoms were reported from as early as 4 weeks after treatment initiation, although it can take a few months to reach the full benefits. Treatment periods of up to 12 months provide sustained benefit to patients. In the most responsive patients, treatment discontinuation is possible with no further substantial relapse over 12 months in over 65% of patients. Transient local ocular effects are the most commonly reported adverse events.

Comparative Evaluation of Matrix Metalloproteinase-9 Immunoassay and Tear Osmolarity Measurement for Diagnosing Severity of Dry Eye Disease

PURPOSE

To evaluate and compare the clinical efficacy of matrix metalloproteinase-9 (MMP-9) immunoassay and tear osmolarity measurement in diagnosing dry eye severity.

METHODS

Dry eye disease (DED) patients underwent diagnostic tests including MMP-9 assay, tear osmolarity measurement, fluorescein tear breakup time, ocular surface staining, anesthetized Schirmer test, Ocular Surface Disease Index questionnaire, and slit-lamp examination. The dry eye parameters were compared according to positive MMP-9 status and increased tear osmolarity. The correlation between dry eye profiles and MMP-9 positivity and high tear osmolarity was also analyzed.

RESULTS

Those who tested positive in MMP-9 immunoassay had significantly higher corneal fluorescein staining score and worse DED severity than those who tested negative. The intensity of MMP-9 positivity showed positive correlation with the corneal staining score and DED severity. However, DED patients with high tear osmolarity above 308 mOsm/L did not show significantly different dry eye signs and symptoms compared to those with lower tear osmolarity values. Tear osmolarity was associated with ocular surface staining score in severe DED patients.

CONCLUSIONS

MMP-9 positivity was associated with ocular surface staining and worse dry eye severity. Therefore, it may be used as a useful indicator of disease severity in conjunction to other diagnostic tests.

Corneal neuroepithelial compartmentalized microfluidic chip model for evaluation of toxicity-induced dry eye

Part of the lacrimal functional unit, the cornea protects the ocular surface from numerous environmental aggressions and xenobiotics. Toxicological evaluation of compounds remains a challenge due to complex interactions between corneal nerve endings and epithelial cells. To this day, models do not integrate the physiological specificity of corneal nerve endings and are insufficient for the detection of low toxic effects essential to anticipate Toxicity-Induced Dry Eye (TIDE). Using high-content imaging tool, we here characterize toxicity-induced cellular alterations using primary cultures of mouse trigeminal sensory neurons and corneal epithelial cells in a compartmentalized microfluidic chip. We validate this model through the analysis of benzalkonium chloride (BAC) toxicity, a well-known preservative in eyedrops, after a single (6h) or repeated (twice a day for 15 min over 5 days) topical 5.10-4% BAC applications on the corneal epithelial cells and nerve terminals. In combination with high-content image analysis, this advanced microfluidic protocol reveal specific and tiny changes in the epithelial cells and axonal network as well as in trigeminal cells, not directly exposed to BAC, with ATF3/6 stress markers and phospho-p44/42 cell activation marker. Altogether, this corneal neuroepithelial chip enables the evaluation of toxic effects of ocular xenobiotics, distinguishing the impact on corneal sensory innervation and epithelial cells. The combination of compartmentalized co-culture/high-content imaging/multiparameter analysis opens the way for the systematic analysis of toxicants but also neuroprotective compounds.

Perfluorohexyloctane in dry eye disease: A systematic review of its efficacy and safety as a novel therapeutic agent

Perfluorohexyloctane (F6H8), a physically and chemically inert synthetic compound, has recently emerged as a promising candidate for the treatment of DED due to its unique properties. A systematic review that only include full-length randomized controlled studies (RCTs), reporting the effects of F6H8 in three databases, PubMed, Scopus and Web of Science, was performed according to the PRISMA statement. The search period was performed between June 1, 2023, and June 21, 2023. The Cochrane risk of bias tool was used to analyze the quality of the studies selected. A total of six RCTs were included in this systematic review. F6H8 tear substitutes treatment achieved a higher improvement than control group interventions in most of the reported variables. The mean differences between both groups were in favor of F6H8 and were as follow: eye dryness score (EDS) base on a visual analogue scale (VAS) of -6.12 ± 4.3 points, ocular surface disease index (OSDI) questionnaire score of -2.8 ± 2.3 points, lipid layer thickness (LLT) of 11.4 ± 10.4 μm, total corneal fluorescein staining (tCFS) of -0.8 ± 0.3 points and ocular treatment-emergent adverse events (TEAEs) of -0.66 ± 1.7. Tear film break-up time (TBUT) was the only variable in favor of control group with a mean of -0.5 ± 0.4 s. Patient satisfaction after F6H8 tear substitutes treatment was high. Therefore, F6H8 tear substitutes improve dry eye symptoms and signs with a satisfactory tolerability and could be recommended in patients with DED.

Mesenchymal stem cell therapy in aqueous deficient dry eye disease

ENGLISH SUMMARY

Dry eye disease (DED) is characterized by ocular dryness, irritation and blurred vision and has a significant impact on the patient's quality of life. This condition can be particularly severe in patients with aqueous deficient dry eye disease (ADDE) due to Sjögren's syndrome (SS), an autoimmune disease that affects the lacrimal and salivary glands. Current treatments for ADDE are often limited to symptomatic relief. A literature review was conducted to explore the current surgical interventions used or tested in humans with ADDE (I). These interventions include procedures involving the eyelids and tear ducts, transplantation of amniotic membrane or salivary glands, injections around the tear ducts and cell-based injections into the lacrimal gland (LG). Each treatment has its advantages and disadvantages; however, treating dry eyes in patients with SS presents a particular challenge due to the systemic nature of the disease. Moreover, there is a need for new therapeutic options. Mesenchymal stem cells (MSCs) are a type of stem cell that have shown promise in regenerating damaged tissue and reducing inflammation in various diseases. Previous studies in animal models have suggested that MSCs could be effective in treating ADDE. Thus, this thesis aims to investigate the safety and efficacy of injecting MSCs into the LG as a treatment option for patients with ADDE secondary to SS. The study also aims to see this treatment in light of existing and novel investigational treatment options. The clinical studies conducted for this thesis are the first of their kind in humans. MSCs derived from healthy donors' adipose tissue (ASCs) were cultured in a laboratory, frozen and thawed ready for use. In the safety study, we performed the first human trial involving the administration of a single injection of ASCs into the LG of one eye in seven patients suffering from severe ADDE (II). The primary objective was to test the safety of this treatment, while the secondary objective was to assess improvements in subjective and objective signs of dry eye. The results of the trial showed no serious side effects within 4 months of follow-up after treatment. On average, there was a 40% reduction in dry eye symptoms assessed with the Ocular Surface Disease Index (OSDI) questionnaire. Additionally, in the treated eye, there was a significant decrease in tear osmolarity, an increase in tear film stability and an increase in tear production. To further investigate the efficacy of this treatment, our research group performed a clinical, randomized study aiming to compare the ASC injection into the LG with the injection of a vehicle (the excipient in which the ASCs are dissolved) and observation (no intervention) (III). The study involved 20 subjects receiving ASC injection, 20 subjects receiving vehicle injection and 14 patients being observed without intervention. The subjects were examined to assess the outcomes with a 12-month follow-up after treatment. Both intervention groups showed a significant reduction in subjective dry eye symptoms of approximately 40%. This improvement was evident at the 1-week follow-up and persisted until the 12-month follow-up. The observation group did not experience any change in OSDI score. The ASCs group exhibited a significant mean increase in non-invasive tear break-up time (NIKBUT) of 6.48 s (149%) at the four-week follow-up, which was significantly higher than that in the vehicle group (p = 0.04). Moreover, the ASCs group showed a significant increase in NIKBUT compared to that in the observation group at the 12-month follow-up (p = 0.004). In both the ASCs and vehicle group, a significant increase in Schirmer test scores at the 4-month follow-up and the 12-month follow-up was observed. In conclusion, this thesis contributes valuable findings with a new treatment option for patients with dry eye disease. Injection of ASCs into the LG was shown to be safe and to improve subjective dry eye symptoms and specifically the tear film stability in patients with ADDE due to SS. Compared to other treatment modalities of ADDE, this treatment has greater potential, as ASCs could potentially be used as an anti-inflammatory therapeutic option for managing DED of other causes as well. RESUMÉ (DANISH SUMMARY): Tørre øjne, karakteriseret ved tørhedsfornemmelse og irritation af øjnene samt sløret syn, har en betydelig indvirkning på patientens livskvalitet. Denne tilstand kan vaere saerligt alvorlig hos patienter med nedsat tåreproduktion (ADDE) som følge af Sjögrens syndrom (SS), en autoimmun sygdom, der påvirker tårekirtlerne og spytkirtlerne. Nuvaerende behandlinger for ADDE er ofte begraenset til symptomlindring. Vi gennemførte en litteraturgennemgang for at undersøge, hvilke nuvaerende kirurgiske behandlingsmetoder, der anvendes eller testes hos patienter med ADDE (I). Disse interventioner inkluderer procedurer, der involverer øjenlåg og tårekanaler, transplantation af amnionhinde eller spytkirtler, injektioner omkring tårekanalerne samt cellebaserede injektioner i tårekirtlen. Hver behandling har sine fordele og ulemper, men behandling af tørre øjne hos patienter med SS udgør en saerlig udfordring på grund af sygdommens systemiske udbredning, og der er behov for nye behandlingsmuligheder. Mesenkymale stamceller (MSCs) er en type stamcelle, der har vist lovende resultater med hensyn til at regenerere beskadiget vaev og reducere inflammation i forskellige sygdomme. Tidligere undersøgelser i dyremodeller har indikeret, at MSCs kan vaere en effektiv behandling af ADDE. Denne afhandling har til formål at undersøge sikkerheden og effekten af injektion af MSCs i tårekirtlen som en mulig behandling til patienter med ADDE som følge af SS. Afhandlingen sigter også mod at sammenligne denne behandling med andre eksisterende, kirurgiske behandlingsmuligheder af ADDE. Som led i dette projekt udførte vi de første kliniske forsøg af sin art i mennesker. MSCs fra raske donorers fedtvaev (ASCs) blev dyrket i et laboratorium, frosset ned og er optøet klar til brug. Det første mål var at teste sikkerheden ved denne behandling og sekundaert at undersøge behandlingens effekt. For at undersøge dette modtog syv forsøgspersoner med svaer ADDE én injektion med ASCs i tårekirtlen på det ene øje (II). Resultaterne af forsøget viste ingen alvorlige bivirkninger inden for fire måneders opfølgning efter behandlingen. I gennemsnit fandt vi yderligere en 40% reduktion i symptomer på tørre øjne vurderet med et spørgeskema, og en markant stigning i tåreproduktionen og af tårefilmens stabilitet i det behandlede øje. For yderligere at undersøge effekten af denne behandling udførte vi et klinisk, randomiseret forsøg med det formål at sammenligne injektion af ASCs i tårekirtlen med injektion af en kontrolopløsning (vaesken, hvor stamcellerne var opløst) og observation (ingen intervention) (III). Studiet omfattede 20 forsøgspersoner, der modtog ASC-injektion, 20 forsøgspersoner, der modtog injektion af kontrolopløsningen, og 14 forsøgspersoner i observationsgruppen. Forsøgspersonerne blev undersøgt med en opfølgningstid på 12 måneder efter behandling. Begge interventionsgrupper viste en betydelig reduktion på ca. 40% i subjektive symptomer på tørre øjne. Denne forbedring var betydelig allerede ved opfølgning efter en uge og varede ved 12 måneder efter behandling. Observationsgruppen oplevede ingen betydelig aendring i symptomer. ASCs gruppen viste desuden en signifikant stigning i tårefilmsstabiliteten (NIKBUT) på 6,48 sekunder (149%) ved opfølgning efter fire uger, hvilket var markant højere end efter injektion af kontrolopløsning (p = 0,04). Desuden viste ASCs gruppen en betydelig stigning i NIKBUT sammenlignet med observationsgruppen ved opfølgning efter 12 måneder (p = 0,004). Både injektion af ASCs og kontrolopløsning medførte en betydelig stigning i tåreproduktionen ved opfølgning fire måneder og 12 måneder efter behandling. Denne afhandling bidrager med vigtige resultater inden for en ny behandlingsmulighed af tørre øjne. Injektion af ASCs i tårekirtlen viste sig at vaere sikker, forbedrede subjektive symptomer på tørre øjne og øgede saerligt tårfilmens stabilitet hos patienter med ADDE på grund af SS. Sammenlignet med andre behandlingsmuligheder for ADDE har denne behandling vist et stort potentiale. ASCs kan muligvis også bruges som en anti-inflammatorisk behandling af tørre øjne af andre årsager i fremtiden.