Clinical review: topical ophthalmic use of cyclosporin A

Selective Tissue Penetration of the Corneal Layers of Cyclosporin 2% Associated with Miglyol in Rabbits

Purpose: Cyclosporin A (CsA) is a drug used to prevent immune rejection in corneal transplantation. Most grafts performed today are endothelial grafts which are complicated with poor penetration of CsA into the endothelium due to its hydrophobicity. To improve CsA penetration into the corneal a new ocular formulation of CsA 2% with Miglyol was developed and is commercially available. The purpose of this pharmacokinetic study was to determine the concentrations of CsA in all layers of the cornea, in particular in the endothelium after topical administration of CsA 2%-Miglyol in rabbits. Methods: Sixteen rabbits were divided in 4 groups according to the time from the last instillation of CsA 2%-Miglyol to corneal sampling. Rabbit eyes received one drop of CsA twice a day for 5 days. Corneal tissue and plasma samples were collected at 2, 6, 12, and 24 h. CsA concentrations were measured using liquid chromatography-tandem mass spectrometry method. Results: Maximum concentrations (Cmax) of CsA were obtained in corneal tissues within 2 h after the last instillation of CsA 2%-Miglyol, except in the endothelium (12 h). Cmax were 59.75 ± 12.09 ng/mg, 15.66 ± 4.31 ng/mg, 5.17 ± 0.88 ng/mg, and 2.65 ± 0.47 ng/mg for the epithelium, endothelium, anterior stroma and posterior stroma. CsA concentrations remained high over a 24-h in all corneal layers. Conclusions: The topical application of CsA 2%-Miglyol allowed a high concentration of CsA in the corneal endothelium. The good penetration of CsA into the endothelium suggests that this formulation can be effective to prevent endothelial graft rejection.

Comparison of therapeutic effects of 0.05% Cyclosporine A versus 0.1% Fluorometholone in Chinese patients with mild dry eye unresponsive to artificial tears: a randomized control study

BACKGROUND

To assess and compare the therapeutic outcomes of 0.05% Cyclosporine A (CsA) ophthalmic solution versus 0.1% Fluorometholone (FML) eyedrops in Chinese patients with mild dry eye disease (DED) unresponsive to conventional artificial tears (AT).

METHODS

A total of 43 patients with mild DED, who have failed to respond to conventional AT therapy for over 3 months, were randomly assigned to receive either 0.05% CsA or 0.1% FML twice daily for 6-months. In addition, all the patients were instructed to use 0.1% SH 4 times a day as supplementary therapy. Dry eye examination, including Ocular Surface Disease Index (OSDI) questionnaire, non-invasive tear break-up time (NIBUT), Schirmer scores, corneal fluorescein staining (CFS) scores, and conjunctival goblet cell (CGC) density, intraocular pressure (IOP), Best corrected visual acuity (BCVA) was conducted at baseline and then evaluated at 1, 3, and 6 months after treatment. Corneal endothelial cell density, corneal dendritic cells (DCs) and nerves were assessed by in vivo confocal microscopy at baseline and 6 months after treatment.

RESULTS

At 3 and 6 months after treatment, OSDI scores in the 0.05% CsA group showed more improvement than those in the 0.1% FML group. CFS was significantly lower and Schirmer scores were significantly higher in 0.05% CsA group compared with 0.1% FML group. NIBUT improved significantly in both groups, with greater improvement in the 0.05% CsA group at the 1-, 3-, and 6-month visits. Throughout the duration of the study, the 0.1% FML group exhibited no notable enhancement in CGC density. Conversely, a substantial elevation in CGC density was observed in the 0.05% CsA group. After 6 months of treatment, significantly reduced corneal DC density and area were obtained in 0.05% CsA group as compared to 0.1% FML group, while there were no significant changes in cornea nerve fiber density, cornea nerve fiber length and cornea nerve fiber width in both groups. Additionally, after 6 months of treatment, neither group showed any statistically significant changes in IOP, BCVA or in corneal endothelial cell density.

CONCLUSION

The administration of 0.05% CsA proved effective in managing mild DED, offering a supplementary advantage in improving Schirmer scores, restoring CGC density and reducing corneal DC density compared to 0.1% FML eyedrops. Consequently, 0.05% CsA eyedrops are recommended as a safe and efficacious therapeutic alternative for patients with mild DED who fail to respond to conventional tear substitutes therapy.

CLINICAL TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry, ChiCTR2200066441, Registered 06 December 2022-Retrospectively registered.

Distinctive small molecules blend: Promotes lacrimal gland epithelial cell proliferation in vitro and accelerates lacrimal gland injury repair in vivo

PURPOSE

This study aims to develop a novel serum-free culture strategy containing only two small molecules, Y27632 and SB431542 (2C), for in vitro expansion of mouse lacrimal gland epithelial cells (LGECs) and investigate an innovative therapeutic approach for lacrimal gland (LG) injury.

METHODS

LGECs proliferative capacity was assessed by cell counting, crystal violet staining, qRT-PCR and immunofluorescence. Cell differentiation was achieved by manipulating culture conditions and assessed by qRT-PCR and AQP5 immunofluorescence. LGECs were seeded in Matrigel for three-dimensional culture and assessed by qRT-PCR and immunofluorescence. Secretory function of the cultures was assayed by ELISA. In vivo, 2C injection verified its reparative capacity in a mouse LG injury model. Corneal fluorescein staining, phenol red cotton thread, H&E, immunofluorescence and Western blot were used to assess LG injury repair.

RESULTS

LGECs cultured with 2C exhibited high expression of stemness/proliferation markers and maintained morphology and proliferative capacity even after the tenth passage. Removal of 2C was efficacious in achieving LGECs differentiation, characterized by the increased AQP5 expression and LTF secretion. 3D spheroids cultured with 2C demonstrated differentiation potential, forming microglandular structures containing multiple LG cell types with secretory functions after 2C removal. In vivo, 2C improved the structural integrity and function of the injured LG.

CONCLUSIONS

We present a small molecule combination, 2C, that promotes LGECs expansion and differentiation in vitro and accelerates LG injury repair in vivo. This approach has potential applications for providing a stable source of seed cells for tissue engineering applications, providing new sights for LG-related diseases treatment.

The evolution of cyclosporine treatments for treatment of ocular surface diseases

PURPOSE OF REVIEW

Cyclosporine is a versatile immunomodulatory drug commonly employed in modern medicine. Although cyclosporine was initially used to prevent solid organ transplant rejection, its indications have extended to treat many inflammatory or autoimmune diseases. Cyclosporin is available for use in oral, intravenous, and topical forms, including eye drops to treat corneal and ocular surface conditions. It is naturally advantageous to administer cyclosporin directly into the eye, avoiding potential and dose limiting systemic adverse effects. However, the transition from systemic to topical administration has been a challenging one. This report reviews the evolution of ophthalmic cyclosporine treatment and explores its clinical impacts and future research directions.

RECENT FINDINGS

Latest advancements in formulations - from oil-based solutions to nanomicelle and gel systems and waterless formulations - have improved the therapeutic efficacy and tolerability of topically applied cyclosporine, demonstrating greater effectiveness in treating ocular surface parameters compared to oil-based solution.

SUMMARY

Cyclosporine continues to be a safe and effective immunomodulatory drug in the field of ophthalmology to treat various chronic inflammatory ocular surface diseases and dry eye. Currently, there are several commercially available topical preparations available for ophthalmic use each with unique formulation and clinical outcomes.

Frequency of Topical Immunomodulatory and Immunosuppressive Therapies for Ocular Chronic Graft-versus-Host Disease

Introduction: The purpose of the study was to evaluate the frequency of topical immunomodulatory and immunosuppressive therapies in patients with ocular chronic graft-versus-host disease (cGVHD) in consideration of inflammatory activity and systemic immunosuppressive therapies in a tertiary care university hospital setting. Methods: We included 95 adult patients (48 male, 47 female) with ocular chronic graft-versus-host disease (cGVHD) after alloHSCT (median age 49.5 years). Clinical ophthalmological findings and the grade of ocular cGVHD according to the NIH eye score and the German-Austrian-Swiss Consensus (GAS) Grading were analyzed. Systemic GVHD manifestations as well as the prevalence of topical and systemic (immunomodulatory) therapies were assessed. Results: A total of 74 of 95 patients (77.8%) had manifestations of systemic chronic graft-versus-host disease other than ocular GVHD. 68.42% (65/95) of patients were under systemic immunosuppressive therapy with at least one immunosuppressive medication. All patients (95/95) received lid-margin hygiene and phosphate- and preservative-free lubricating eye drops. Twenty-five percent of the cohort (24/95) were treated with autologous serum eye drops (ASEDs). In total, 80% (76/95) of patients required topical steroid therapy to treat acute exacerbation of inflammation at least once; continuous topical steroid therapy was only necessary for a minor part (12%) with refractory chronic inflammation. A total of 92.63% (88/95) were primarily treated with ciclosporin A 0.1% as Ikervis®, of whom at least one third did not continue the therapy because of intolerable side effects during follow-up and received alternative topical formulations. Conclusions: Our data show that patients with ocular cGVHD mostly need topical therapy including anti-inflammatory agents despite systemic immunosuppressive therapy. In our cohort, 80% of patients received topical steroids, and more than 90% received topical ciclosporin A eye drops, which were tolerated by only two thirds of patients due to side effects.

Spontaneous bilateral corneal perforation in ocular Rosacea

PURPOSE

To report a rare case of a 19-year-old girl who presented with spontaneous bilateral corneal perforation in a setting of ocular rosacea.

METHODS

Ocular rosacea was diagnosed and treated with doxycycline. Cyanoacrylate glue was applied to treat corneal perforations.

RESULTS

At six months follow up there is good healing, visual acuity has improved, anterior chamber is deep with no Seidel.

CONCLUSIONS

Rosacea is a multifactorial disease with an unclear pathophysiology. The ocular manifestations of rosacea (ocular rosacea) may occur without skin involvement, are not specific and can range from mild blepharitis to sight-threatening conditions. This case shows how ocular rosacea can lead to serious vision-threatening complications with mild symptoms. Cyanoacrylate glue and systemic antibiotic treatment are effective treatments.

Applications of topical immunomodulators enhance clinical signs of vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC): a meta-analysis

PURPOSE

This meta-analysis aimed to review the safety and efficacy of topical cyclosporine A (CsA) and topical tacrolimus in allergic eye disease.

METHODS

A systematic search identified thirteen studies and a total of 445 patients for inclusion, making this the largest meta-analysis published on the subject. The current review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

Thirteen randomized control trials were included in the meta-analysis. Eleven studies used CsA as the treatment, and two used Tacrolimus. In total, 445 participants were included, of whom 76.6% were male. The mean age of participants across the included studies was 14 years. All studies reported clinical signs as evaluated by an examining clinician. Signs were usually assessed by anatomical region, with the most common regions being the conjunctiva and the cornea, and the most common signs assessed were hyperemia and papillae. Three studies accounted for more than 50% of the meta-analysis's weight. Effect size (d) ranged from - 2.37 to - 0.03, negative values favoring immunomodulators. Fixed Effect Meta-Analysis returned an SMD of - 0.81 (95% CI [- 0.98, - 0.65]). However, there was significant heterogeneity (I2 = 61%, Qw = 30.76) in the outcome measure (P = 0.0021); therefore, a random-effect meta-analysis was also completed in which the pooled SMD was - 0.98 (95% CI [- 1.26, - 0.69], τ2 = 0.16).

CONCLUSIONS

This study affirms the current scientific community's stance that immunomodulators effectively treat clinical signs, including blepharitis, conjunctival hyperemia, edema, papillae, and corneal damage in severe ocular allergic disease.

A Randomized, Controlled Trial Comparing Tearcare® and Cyclosporine Ophthalmic Emulsion for the Treatment of Dry Eye Disease (SAHARA)

Purpose

We compare outcomes in eyes with dry eye disease (DED) treated with TearCare (TC) or topical cyclosporine 0.05% (RESTASIS; CsA).

Setting

Nineteen ophthalmic and optometric practices in 11 US states.

Design

Multicenter, randomized, assessor-masked, controlled IRB-approved trial. Eligible subjects: ≥22 years of age, dry eye symptoms within 3-6 months, Tear Break-up Time (TBUT) ≥1 to ≤7 s, Meibomian Gland Secretion Score (MGSS) ≤12, Ocular Surface Disease Index (OSDI) of 23-79. Randomized (1:1) to TC or CsA. TC subjects treated at baseline and month 5; CsA was twice daily for 6 months.

Methods

Follow-up visits were scheduled for Day 1, Week 1, Months 1, 3, and 6 with primary inference at Month 6. Primary outcomes: TBUT and OSDI; secondary outcomes: MGSS, conjunctival and corneal staining, eye dryness score (EDS), symptoms assessment in dry eye (SANDE) score, and Schirmer tear score (STS). Safety assessments included adverse events, best corrected visual acuity, intraocular pressure, and slit-lamp findings.

Results

Overall, 345 subjects, 172 TC and 173 CsA. TBUT improved at all time points in both groups (p<0.0001), with statistically greater improvement for TC versus CsA (p=0.0006). OSDI improved significantly at all time points in both groups (p<0.0001) with no significant differences between treatments. MGSS and other measures of meibomian gland function improved significantly more with TC eyes versus CsA; other secondary outcomes showed significant improvements in both groups with no difference between groups. Treatment-related adverse events were uncommon (10 total, 8 in the CsA group consistent with prior CsA studies); most (9/10) mild.

Conclusion

TC provides statistically superior and sustained improvement in TBUT and multiple measures of meibomian gland secretion, and non-inferior improvement in OSDI, corneal and conjunctival staining, SANDE, EDS, and STS versus CsA. TC should be a preferred treatment for DED associated with MGD.

Microscopic and Biopharmaceutical Evaluation of Emulsion and Self-Emulsifying Oil with Cyclosporine

Among the currently available commercial eye drops with cyclosporine A (Cs) there is a lack of long-acting dosage forms and products with a concentration of the drug substance higher than 0.1%, although Cs is widely used in ophthalmology. The aim of the research was to conduct the microscopic and biopharmaceutical evaluation of two formulations, an emulsion (EM) and a self-emulsifying oil (SEO), both with 0.5% of Cs, proposed for use in eye drops, and the comparison of both. SEO eye drops with Cs or any other drug substance are currently not available as marketed products, and the highest concentration of Cs in the ocular emulsion is only 0.1%. The microscopic evaluation of the emulsion and the SEO after emulsification with water was carried out using a high-resolution digital microscopy. The properties of both preparations were compared using the high dynamic range function or optical shadow effect mode. Images in the 3D composition mode were also recorded. The in vivo study of the Cs formulations was performed on male albino rabbits. The eye tolerance of the preparations was assessed using the ocular irritation test, which is a modified Draize test. Placebo carriers (without the drug substance) were also subjected to irritation testing. The concentration of Cs in the tissues (cornea and conjunctiva) and fluids (tear fluid and aqueous humor) of the rabbit eye was determined after multiple instillations of Cs-EM or Cs-SEO. The tested preparations were compared using the digital microscopy technique, which highlights the features of the formulations and eliminates the risk of unnoticeable properties that are difficult to observe in classical optical microscopy. Both tested Cs-loaded formulations are classified as practically non-irritating. There were also no significant differences when testing the placebo carriers. After a topical administration, Cs was widely distributed in all tissues (e.g., in cornea 1.3 ng/mg and 1.0 ng/mg) and fluids of the eye (e.g., in tear fluid 11.6 µg/mL and 4.3 µg/mL), after the administration of Cs-SEO and Cs-EM, respectively. The obtained results allow us to recognize both tested formulations, the emulsion and the self-emulsifying oil with 0.5% Cs content, as carriers safe for ophthalmic use and effective in delivering the drug substance to the structures of the eye.

Research progress of ophthalmic preparations of immunosuppressants

Immune ophthalmopathy is a collection of autoimmune eye diseases. Immunosuppressants are drugs that can inhibit the body's immune response. Considering drug side effects such as hepatorenal toxicity and the unique structure of the eye, incorporating immunosuppressants into ophthalmic nanodrug delivery systems, such as microparticles, nanoparticles, liposomes, micelles, implants, and in situ gels, has the advantages of improving solubility, increasing bioavailability, high eye-target specificity, and reducing side effects. This study reviews recent research and applications of this aspect to provide a reference for the development of an ophthalmic drug delivery system.

Application of topical 2% cyclosporine A in inflammatory ocular surface diseases

PURPOSE

To report our experience with the 2% cyclosporin A (CsA) in a series of challenging inflammatory ocular surface diseases due to different etiologies.

METHODS

The records of patients who received topical 2% CsA for different indications were reviewed retrospectively. Demographic characteristics, indications for treatment, patient symptoms and clinical findings were recorded.

RESULTS

Fifty-two eyes of 52 patients were included. Mean age was 43.2 ± 14.3 (11-66) years with a F/M ratio of 34/18. Indications included pediatric acne rosacea (n = 4), adenoviral corneal subepithelial infiltrates (n = 12), filamentary keratitis (n = 14), pterygium recurrence (n = 15), herpetic marginal keratitis (n = 2) and graft versus host disease (n = 5 patients). Mean duration of treatment was 7.3 ± 2.8 (3-10) months. Forty-three (83%) patients reported favorable outcome with improvement in symptoms after a mean time of 4.4 ± 2.7 (2-6) months.

CONCLUSIONS

Topical 2% CsA may address the needs of different cases with ocular surface inflammation, as a safe option for long-term therapy.

Preclinical characterization of water-free cyclosporine eye drops - factors impacting ocular penetration ex vivo and in vivo

Although the efficacy of Cyclosporine A (CsA) in the management of ocular inflammation is well-demonstrated, ocular delivery remains challenging due to its hydrophobic nature. The semifluorinated alkane, perfluorobutylpentane (F4H5) has previously been suggested as an efficient vehicle for preparation of CsA eyedrops. Here we evaluated the influence of drop volume and the formulation aid, ethanol (EtOH), on ocular penetration of CsA and compared it to that of the commercial eyedrop, Ikervis, ex vivo and in vivo. Moreover, conjunctival and corneal tolerability after EtOH addition were evaluated ex vivo. The F4H5/EtOH vehicle was well tolerated and resulted in better corneal CsA penetration (AUC_{(0 - 4h)}: 63,008 ± 3,946 ng.h.g^-1) than Ikervis (AUC_{(0 - 4h)}: 10,328 ± 1,462 ng.h.g^-1) or F4H5 alone (AUC_{(0 - 4h)}: 50,734 ± 3,472 ng.h.g^-1) ex vivo. Interestingly, in vivo the CsA concentration in cornea, conjunctiva and lacrimal glands observed after administration of the F4H5 formulation (AUC_{(0.133-24 h)}: 7,741 ± 1,334 ng.h.g^-1, 1,313 ± 291 ng.h.g^-1, 48.2 ± 26.3 ng.h.g^-1) and F4H5/EtOH both at a reduced dose of 11 µl (AUC_{(0.133-24 h)}: 9,552 ± 1,738 ng.h.g^-1, 1,679 ± 285 ng.h.g^-1, 50.3 ± 21.1 ng.h.g^-1) was similar or even greater than what was observed on administration of 50 µl Ikervis (AUC_{(0.133-24 h)}: 9,943 ± 1,413 ng.h.g^-1, 2,069 ± 263 ng.h.g^-1, 30.6 ± 18.4 ng.h.g^-1). Thus, F4H5-based eyedrops were shown to deliver CsA more efficiently to anterior ocular tissues at a reduced dose in comparison to Ikervis, reducing dose wastage and minimizing any potential systemic side effects.

Diagnostic approach and grading scheme for canine allergic conjunctivitis

BACKGROUND

In humans, allergic conjunctivitis is a well described disease. In contrast, allergic conjunctivitis has not received much attention from the veterinary community so far. Canine allergic conjunctivitis (cAC) is one of the possible manifestations associated with canine atopic dermatitis (cAD), being often underdiagnosed and undertreated. Our aim is to contribute to disease characterization and clinical stagingfor cAC severity.

RESULTS

A retrospective observational study including 122 dogs that underwent a complete ophthalmological and dermatological examinations and diagnosed with allergic conjunctivitis was conducted. A total of six ophthalmic clinical signs were considered for disease characterization and clinical staging: conjunctival hyperemia, chemosis, ocular pruritus, epiphora, seromucoid to mucopurulent discharge and keratitis, classified from 0 (absent) to 3 (severe). Scores comprised between 1-5 were considered mild, 6-10 moderate and 11-18 severe. The majority of dogs (64%) presented with moderate cAC followed by 24% of mild stages and only 12% of severe presentations. The severity of allergic conjunctivitis was not correlated to sex or age at the time of diagnosis and all presented with a bilateral form of the disease. Chemosis (84%), hyperemia (83%) and ocular pruritus (79%) was observed in 55% of the cases. Seromucoid to mucopurulent discharge (62%) and epiphora (69%) were less frequent, with keratitis being the least encountered clinical sign (15%). The degree of keratitis showed a positive correlation with both severity and chronicity of cAC (rho = 0.21-0.29, p ≤ 0.02)). Severity of cAD and cAD were not significantly correlated (p-value = 0.4).

DISCUSSION AND CONCLUSION

The triad hyperemia, chemosis and ocular pruritus, already known in human medicine to be a reliable way of diagnosing human allergic conjunctivitis, also proved to be important in cAC Mild forms of the disease may pass unnoticed, ocular pruritus being hard to assess in canine patients.The proposed standardized diagnostic approach and novel grading scheme for cAC may be of value for both veterinary ophthalmologists and dermatologists, as well as general practitioners.

Cellulose Acetate Phthalate-Based pH-Responsive Cyclosporine A-Loaded Contact Lens for the Treatment of Dry Eye

Cyclosporine A (CsA) as an eye drop is an effective treatment for dry eye. However, it has potential side effects and a short ocular residence time. To overcome these obstacles, we developed a cellulose acetate phthalate-based pH-responsive contact lens (CL) loaded with CsA (CsA-CL). The CsA was continuously released from the CsA-CL at physiological conditions (37 °C, pH 7.4) without an initial burst. CsA was well-contained in the selected storage condition (4 °C, pH 5.4) for as long as 90 days. In safety assays, cytotoxicity, ocular irritation, visible light transmittance, and oxygen permeability were in a normal range. CsA concentrations in the conjunctiva, cornea, and lens increased over time until 12 h. When comparing the therapeutic efficacy between the normal control, experimental dry eye (EDE), and treatment groups (CsA eye drop, naïve CL, and CsA-CL groups), the tear volume, TBUT, corneal fluorescein staining at 7 and 14 days, conjunctival goblet cell density, and corneal apoptotic cell counts at 14 days improved in all treatment groups compared to EDE, with a significantly better result in the CsA-CL group compared with other groups (all p < 0.05). The CsA-CL could be an effective, stable, and safe option for inflammatory dry eye.

[Modern possibilities of pathogenetically oriented therapy for dry eye syndrome]

In recent years, anti-inflammatory therapy has become a significant part of the complex approach to treatment of patients with dry eye syndrome (DES), with cyclosporine preparations becoming increasingly important in the structure of the therapy. Taking into account the immunosuppressive effect of cyclosporine A, which is realized through hindering the activation of T-lymphocytes in the tissues of the ocular surface, its topical application in DES has a pronounced pathogenetic focus. Numerous clinical studies have shown that instillations of cyclosporine into the conjunctival cavity contribute to an increase in total tear production, as well as recovery of the density of goblet cells in the conjunctiva of DES patients. The positive effect of cyclosporine A instillations has been convincingly demonstrated in the complex therapy of patients with vernal and atopic corneal conjunctivitis, Thygeson's superficial punctate keratitis, autoimmune keratitis, meibomian gland dysfunction, etc. However, one significant problem associated with cyclosporine A instillations is the irritating effect of the drug. That prompted the development of a drug that is safe and tolerable during instillations into the conjunctival cavity - preservative-free 0.1% cyclosporine A labelled Ikervis (Santen, Japan). The drug carrier is artificial tear Cationorm (Santen), which has an advantage of stabilizing the tear film and protecting the ocular surface from the irritating effect of cyclosporine. According to numerous clinical studies, Ikervis instillations can improve the effectiveness of complex therapy in patients with DES (especially secondary to Sjögren syndrome, Stevens-Johnson syndrome, graft-versus-host disease), with allergic diseases of the cornea and conjunctiva (spring, atopic corneal conjunctivitis), with corneal transplant disease, and other similar conditions. The high efficacy and safety of Ikervis constitute the reason to recommend it for wide clinical use.

Comparison of seven cyclosporine A formulations for dry eye disease: A systematic review and network meta-analysis

Background: Dry eye disease is a common ocular surface disease affecting tens of millions of people worldwide. It is characterized by an unstable tear film and increasing prevalence. Different commercial formulations of cyclosporine A for dry eye have been approved, however, it is still unclear whether the differences in formulations of these products will make a difference in clinical efficacy and safety. Methods: Randomized controlled trials of commercial cyclosporine A formulation for dry eye disease were searched in Pubmed, EMBASE, Scopus, and Cochrane controlled trials registries and Web of Science from inception till 1 December 2021. Independent literature screening, data extraction, quality evaluation, and the study in line with quality standards were analyzed by using Stata16.0 software. The study is registered with PROSPERO under the number CRD42022301423. Code and data for this study is publicly available (https://github.com/DongYangGao/Dongyang.github.io.git). Results: 21 randomized clinical trials with a total of 4,107 participants were included in this study. Restasis® (OR-4.82, 95% CI-6.18 to 3.45, SUCRA 77.2%) was the most effective commercial formulation for reducing OSDI, Zirun® (SUCRA 73.9%) performed better in improving Schirmer's test. TJ Cyporin® (SUCRA 65.3%) ranked first in terms of improving tear film break-up time. For treatment-emergent adverse events incidence, Clacier® was close to placebo. The risk of reporting bias is considered low. Conclusion: In the comparison of outcomes included in this study, the optimal order of various commercial cyclosporine A formulations is different, so it is difficult to select the optimal formula. Appropriate commercial formulations should be selected according to patients' conditions in clinical practice.

Cyclosporine A Delivery Platform for Veterinary Ophthalmology—A New Concept for Advanced Ophthalmology

Cyclosporine A (CsA) is a selective and reversible immunosuppressant agent that is widely used as a medication for a wide spectrum of diseases in humans such as graft versus host disease, non-infectious uveitis, rheumatoid arthritis, psoriasis, and atopic dermatitis. Furthermore, the CsA is used to treat keratoconjunctivitis sicca, chronic superficial keratitis, immune-mediated keratitis and equine recurrent uveitis in animals. The selective activity of Cyclosporine A (CsA) was demonstrated to be an immunomodulation characteristic of T-lymphocyte proliferation and inhibits cytokine gene expression. Moreover, the lipophilic characteristics with poor bioavailability and low solubility in water, besides the side effects, force the need to develop new formulations and devices that will provide adequate penetration into the anterior and posterior segments of the eye. This review aims to summarize the effectiveness and safety of cyclosporine A delivery platforms in veterinary ophthalmology.

Linoleic Acid-Based Transferosomes for Topical Ocular Delivery of Cyclosporine A

Delivering high-molecular-weight hydrophobic peptides, such as cyclosporine A, across the corneal epithelium remains a challenge that is complicated by other physio-anatomical ocular structures that limit the ocular bioavailability of such peptides. Transferosomes have previously been used to improve transdermal permeability, and have the potential for improving the ocular corneal permeability of applicable drugs. In this study, transferosomes for the potential ocular delivery of cyclosporine A were investigated. Linoleic acid was evaluated for its effect on the stability of the transferosomes and was substituted for a portion of the cholesterol in the vesicles. Additionally, Span® 80 and Tween® 80 were evaluated for their effect on transferosome flexibility and toxicity to ocular cells as edge activators. Attenuated Total Reflectance–Fourier Transform Infrared spectroscopy (ATF-FTIR), differential scanning calorimetry (DSC), and dynamic light scattering (DLS) were used to evaluate the physicochemical parameters of the blank and the cyclosporine A-loaded transferosomes. Cyclosporine A release and corneal permeability were studied in vitro and in a New Zealand albino rabbit corneal model, respectively. The linoleic acid contributed to improved stability and the nano-size of the transferosomes. The Tween®-based formulation was preferred on the basis of a more favorable toxicity profile, as the difference in their corneal permeability was not significant. There was an initial burst release of cyclosporine A in the first 24 h that plateaued over one week. The Tween®-based formulation had a flux of 0.78 µg/cm2/h. The prepared transferosomes demonstrated biocompatibility in the ocular cell line, adequately encapsulated cyclosporine A, ensured the corneal permeability of the enclosed drug, and were stable over the period of investigation of 4 months at −20 °C.

Therapeutic Applications of Adeno-Associated Virus (AAV) Gene Transfer of HLA-G in the Eye

The purpose of this paper is to review human leukocyte antigen G (HLA-G) in the eye, its role in immune tolerance, and the potential therapeutic use of AAV gene transfer and expression of HLA-G in various ocular tissues. Several studies are reviewed that demonstrate efficacy in animal models of disease, including intracorneal delivery of AAV-HLA-G to treat corneal inflammation and prevent corneal graft rejection, subconjunctival injection of AAV-HLA-G for ocular graft vs. host disease and potentially dry eye disease, and intravitreal injection of AAV-HLA-G to inhibit uveitis. Furthermore, due to the anti-vascular function of HLA-G, AAV-HLA-G may be an effective therapy for posterior ocular diseases, such as neovascular age-related macular degeneration, diabetic retinopathy, and choroidal neovascularization. Therefore, AAV-mediated gene transfer of HLA-G may be an effective treatment for common immune-mediated, inflammatory, and neovascular diseases of the eye.

Cyclodextrin-Containing Hydrogels: A Review of Preparation Method, Drug Delivery, and Degradation Behavior

Hydrogels possess porous structures, which are widely applied in the field of materials and biomedicine. As a natural oligosaccharide, cyclodextrin (CD) has shown remarkable application prospects in the synthesis and utilization of hydrogels. CD can be incorporated into hydrogels to form chemically or physically cross-linked networks. Furthermore, the unique cavity structure of CD makes it an ideal vehicle for the delivery of active ingredients into target tissues. This review describes useful methods to prepare CD-containing hydrogels. In addition, the potential biomedical applications of CD-containing hydrogels are reviewed. The release and degradation process of CD-containing hydrogels under different conditions are discussed. Finally, the current challenges and future research directions on CD-containing hydrogels are presented.

Dupilumab-associated ocular surface disease: presentation, management and long-term sequelae

OBJECTIVES

To determine the presenting features of ocular surface disease in patients with atopic dermatitis (AD) treated with dupilumab at a tertiary, university hospital. To establish the need for treatment of dupilumab-associated ocular surface disease and report any long-term effects on the ocular surface.

METHODS

A retrospective analysis of consecutive patients treated with dupilumab for AD between January 2017 and August 2019 was undertaken. Data were collected on demographics, incidence and type of ocular disease features, natural history and treatment.

RESULTS

A total of 50% (14/28) patients developed ocular symptoms with a mean time of onset of 6.75 (±6.1) weeks from starting dupilumab. Of these, 69% (9/13) were diagnosed with conjunctivitis associated with cicatrisation in two patients and periorbital skin changes in four. Of these nine, four had prior history of atopic keratoconjunctivitis. All were treated with topical steroids; two required additional ciclosporin drops. In all, 67% (6/9) patients went on to have on-going ocular inflammation requiring maintenance drops at a mean of 16 (±6.9) months of follow-up. All patients had improvement in their AD severity; only one patient discontinued dupilumab due to ocular side effects.

CONCLUSION

The rate of dupilumab-associated ocular surface disease was 32%. Periorbital skin changes and conjunctival cicatrisation were noted in association with conjunctivitis. Ocular surface disease improved on topical steroids and ciclosporin but 67% of patients needed on-going treatment. Close liaison with an ophthalmologist should be considered in those patients who develop conjunctivitis or have a past history of severe ocular surface disease.

Corneal lymphangiogenesis as a potential target in dry eye disease - a systematic review

Dry eye disease (DED) is a common ocular surface condition causing symptoms of significant discomfort, visual disturbance, and pain. With recent advancements, DED has become recognized as a chronic self-perpetuating inflammatory condition triggered by various internal and environmental factors. DED has been shown to arise from the activation of both the innate and adaptive immune systems, leading to corneal epithelium and lacrimal gland dysfunction. While the cornea is normally avascular and thus imbued with angiogenic and lymphangiogenic privilege, various DED models have revealed activated corneal antigen-presenting cells in regional lymph nodes, suggesting the formation of new corneal lymphatic vessels in DED. The recent availability of reliable lymphatic cell surface markers such as LYVE-1 has made it possible to study lymphangiogenesis. Accordingly, numerous studies have been published within the last decade discussing the role of lymphangiogenesis in DED pathology. We systematically review the literature to identify and evaluate studies presenting data on corneal lymphangiogenesis in DED. There is considerable evidence supporting corneal lymphangiogenesis as a central mediator of DED pathogenesis. These findings suggest that anti-lymphangiogenic therapeutic strategies may be a viable option for the treatment of DED, a conclusion supported by the limited number of reported clinical trials examining anti-lymphangiogenic modalities in DED.

Topical corticosteroids with topical cyclosporine A versus topical corticosteroids alone for immunological corneal graft rejection

PURPOSE

To assess the efficacy and safety of supplementing topical cyclosporine A (CsA) to topical corticosteroids (CS), in the prophylaxis and treatment of corneal graft rejection following penetrating keratoplasty (PK).

METHODS

Meta-analysis. Search was performed in PubMed, CENTRAL, ClinicalTrials.gov, reference lists of articles and conference proceedings. Primary outcomes: 1-year rejection-free survival rate (prophylaxis); resolution rate of rejection episodes (treatment). Secondary outcomes: 6- and 24-month rejection-free graft survival rate, number of rejection episodes during follow-up, time-to-resolution of rejection episode, 12- and 24-months graft survival rate, adverse events. Subgroup analyses were planned for high-risk grafts; primary vs. secondary prophylaxis of graft rejection episodes; and CsA concentrations of 0.05%, 1%, and 2%.

RESULTS

Five studies of moderate methodological quality were included (one retrospective, four RCT), assessing 459 eyes (CS + CsA 226, CS 233). In the prophylaxis setting, supplemental CsA was associated with a higher rejection-free survival rate at 12-months (RR 1.25, 95% CI: 1.00-1.56, p = 0.05) and 24-months post-PK (RR 1.56, 95% CI: 1.15-2.11, p < 0.01), though no differences were found at the 6-months timepoint (p = 0.93). This effect was mostly verified using CsA 2% in the high-risk subset of patients. In the treatment setting, no differences were found in the resolution rate of rejection episodes (p = 0.23). No differences existed on drug-related adverse events.

CONCLUSION

In the prophylaxis of rejection episodes post-PK, the combined regimen of CS + CsA was associated with a higher 1- and 2-year rejection-free graft survival rate. Subgroup analysis mostly supported the use of CsA 2% for high-risk grafts. Further studies are needed to validate these results.

Algorithmic approach to diagnosis and management of post-refractive surgery dry eye disease

Dry eye disease (DED) is a condition that is fast reaching epidemic proportions around the world. Dry eye post-refractive surgery is the leading cause of iatrogenically induced DED. The wide variety of presentations and the disparity between signs and symptoms in many patients make this a very challenging aspect of our clinical practice. There has been a paradigm shift in the way we approach and treat this condition. The International Dry eye workshop has added new knowledge and focus to our management of dry eye. A wide range of newer diagnostic modalities are available for the diagnosis of DED. Dry eye is one of the most common side effects of refractive surgery and can have a bearing the patient's perception of surgical outcomes as well. A thorough understanding of the possible underlying etiopathologies of this disease and the difference in etiopathogenesis of postrefractive dry eye is essential for optimal outcomes. It is important to approach each case in a unique fashion and customize the therapy to the patient presentation. This review article compiles all these aspects of management of dry eye in general, and postrefractive surgery dry eye in particular; from the ones commonly practiced in the clinic to the newer modalities of therapy with insights into the disease from a more practical point of view.

Update on Idiopathic Canalicular Inflammatory Disease (ICID): Outcomes With Addition of Topical Cyclosporine and the Modified Treatment Protocol

PURPOSE

The objective of this study is to present clinical outcomes with addition of topical cyclosporine while managing cases of "idiopathic canalicular inflammatory disease" and to propose a modified treatment protocol.

METHODS

Prospective case series of 88 canaliculi of 44 eyes of 22 patients diagnosed as "idiopathic canalicular inflammatory disease" at a tertiary care Dacryology service over a period of 2 years. All the patients were diagnosed based on the published major and minor criteria and each of the canaliculus was clinically staged. All patients were treated initially with a combination of topical cyclosporine (0.05%) and rapidly tapering topical steroids followed by punctal dilatation and placement of mini-monoka stents after control of inflammation. Monoka stents were extubated at 6 weeks and the cyclosporine was continued for at least up to 3 months beyond the extubation of stents. Patient demographics, investigations, response to cyclosporine, management modalities, recurrence of inflammation, anatomical and functional outcomes were analyzed.

RESULTS

Eighty-eight canaliculi were diagnosed to have idiopathic canalicular inflammatory disease during the study period. There was a female preponderance (77%, 17/22) and the mean age at presentation was 51 years. All patients presented with bilateral epiphora (mean duration 4.5 months) without any discharge. Staging revealed 18, 27, 24, and 19 canaliculi were involved with stages 1-4, respectively. The mean duration of cyclosporine use was 5.7 months. All patients except 3 (19/22) underwent monoka dilatation. Complete anatomical and functional resolution were noted in 62% (55/88), of which 12 puncta and canaliculi, all stage 1 (13.6%, 12/88) showed complete resolution with cyclosporine alone. Relentless disease progression to stage 5 was noted in 30% (26/88) of the puncta and canaliculi. All the younger patients (<30 years, 13.6%, 3/22) demonstrated poor outcomes.

CONCLUSIONS

The addition of topical cyclosporine is beneficial in controlling inflammation and disease downstaging in patients with idiopathic canalicular inflammatory disease. The current modified treatment protocol salvages majority of the canaliculi.

Immunosuppressive activity of daphnetin on the humoral immune responses in ovalbumin-sensitized BALB/c mice

INTRODUCTION

Most of the immunosuppressive drugs are used for the treatment of autoimmune disease, allergic diseases, and transplant rejection, but toxicity is the major obstacle for the potent drugs in the wide use of these immunosuppressive drugs. Daphnetin, a Chinese herbal product, has been reported that daphnetin possesses antimicrobial, anticoagulation, antimalarial, anticancer, and antioxidant activity. In a previous study, we found that daphnetin exhibited a potential immunosuppressive effect on LPS-induced B lymphocyte cells in vitro, therefore, in this research, we investigated the immunosuppressive effects of daphnetin in BALB/c mice use OVA as a prototype antigen.

METHODS

Sixty BALB/c mice were divided into six groups. The emulsion (100 μL containing 100 μg OVA) was injected subcutaneously with OVA + CFA into the shaved backs of the BALB/c mice on day 1, and a boosting injection was administered in OVA + IFA 2 weeks later. Beginning on the day of immunization, the immunized mice were administered intraperitoneally with daphnetin at a dose of 5, 10, and 20 mg/kg in saline solution for 28 consecutive days. We measured the effect of daphnetin on OVA-specific antibody, cytokine production, and Splenocyte proliferation in vivo.

RESULTS

The results revealed that daphnetin significantly suppressed serum immunoglobulin G levels (IgG), and the OVA-specific IgG subclasses IgG1 and IgG2b, daphnetin was also significantly decreased the Th1 and Th2 cytokine productions, inhibited the splenocytes proliferation rate in vivo.

CONCLUSIONS

It proved that daphnetin could suppress humoral response activity on OVA-sensitized mice, suggesting a potential role on daphnetin as a new immunosuppressive drug.

Late-term topical tacrolimus for subepithelial infiltrates resistant to topical steroids and ciclosporin secondary to adenoviral keratoconjunctivitis

PURPOSE

Investigation of the efficacy and safety of 12 months of topical tacrolimus 0.03% ointment treatment against the subepithelial infiltrates (SEIs) due to adenoviral keratoconjunctivitis (AKC) resisting at least 2 years was aimed.

METHODS

This case series included consecutive patients with SEIs secondary to AKC who were resistant to topical steroid and ciclosporin-A (CSA) treatment and treated with topical 0.03% tacrolimus (Protopic; Fujisawa Healthcare, Teva, Deerfield, Illinois, USA) for 12 months, at least 2 years after AKC. For the evaluation of treatment efficacy, best-corrected visual acuity (BCVA), Fantes score, corneal subepithelial infiltrate score (CSIS), Oxford score, Schirmer and tear breakup time results were evaluated. Intraocular pressure and complaints of the patients were followed for evaluating the safety profile of the treatment. The patients were followed after the baseline visit at the 1st, 3rd, 6th and 12th month.

RESULTS

15 eyes of 11 patients with SEIs and 16 eyes of 16 healthy controls were included in this study. 1 patient (9.1%) could not tolerate the treatment. Significant improvements in BCVA, CSIS, Fantes score and Schirmer results were observed in the study group starting from the 3rd-month visit, and the improvements persisted until the end of 12 months of treatment.

CONCLUSION

Topical 0.03% tacrolimus might show efficacy against the SEIs persisting at least 2 years despite corticosteroid and/or CSA treatment without any prominent side effect. While at least a period of 3 months was necessary for a significant improvement in the BCVA, SEIs and Schirmer results, a period of 6 months was necessary for a decrease in Oxford score.

Tolerance and Adherence to Cationic 0.1% Cyclosporine in Ocular Graft-versus-Host Disease

INTRODUCTION

Anti-inflammatory, topical therapy of severe keratitis in dry eye disease (DED) and ocular graft-versus-host disease (oGvHD) includes steroids, cyclosporine (Cs), and others. In Germany, a commercial product containing 0.1% Cs in a cationic formulation is available since 2015.

OBJECTIVE

The aim of this study was to present real-life data using cationic 0.1% Cs in oGvHD patients.

METHODS

This was a retrospective study of 26 oGvHD and 41 DED patients with corneal staining of at least Oxford grade III. Parameters analyzed were Ocular Surface Disease Index, corneal staining, intraocular pressure, tear film break-up time, Schirmer, and visual acuity. In addition, it was evaluated how different Cs formulations were tolerated.

RESULTS

Corneal staining improved significantly in 1 eye in DED but not in oGvHD. In DED, cationic 0.1% Cs was not tolerated by 32% of the patients, in contrast to 0.05% Cs in castor oil not tolerated by 47% and liposomal 0.05% Cs by 63%. In oGvHD patients, cationic 0.1% Cs was not tolerated by 62%, 0.05% Cs in castor oil by 33%, and liposomal 0.05% Cs by 39% of the patients.

CONCLUSIONS

This study demonstrates differences between the tolerance of different Cs formulations depending on the underlying cause of severe keratitis. Cationic 0.1% Cs is considerably less tolerated in oGvHD, and its use should be considered with care.

Corneal graft melting: a systematic review

Corneal graft melting is a severe complication of keratoplasty. This review is to summarize the incidence, the pathogenesis, the risk factors, the prognosis and the prevention of corneal graft melting after keratoplasty. We systematically searched PubMed, Web of Science and WanFang database to retrieve potentially eligible articles about relevant clinical reports and animal experiments. We read the full texts to identify eligible articles. The selection of studies and data extraction were performed independently by two reviewers. In conclusion, the pathogenesis of corneal graft melting is complicated, and many risk factors are closely related to corneal graft melting. Analysis of pathogenesis and risk factors of corneal graft melting can facilitate the development of targeted therapies to better guide clinical practice.

Management of vernal keratoconjunctivitis in children in Saudi Arabia

Vernal keratoconjunctivitis is a chronic inflammatory disease of the ocular surface and one of the worst types of allergic conjunctival diseases. Because of its chronic nature, it can damage the cornea, resulting in sight-threatening complications if left untreated. The disease affects mainly young children starting around the age of 7 years. We used keywords to search for published English articles in PUBMED, Google Scholar, EMBASE, and Cochrane Database of Systematic Reviews. Most of the published literature is focusing on general management of the disease and few publications focusing on treatment in the pediatric age group. We highlight the importance of how is the topical management differs between age groups. We focused on the importance of doing cycloplegic refraction for each child as the risk of keratoconus and oblique astigmatism is high in these cases. Furthermore, we highlight the importance of using eye lubricants as a therapeutic and preventive tool for the attacks of the disease. We highlight that most of the recent effective medications (especially the off-label ones) are not available in Saudi Arabia, such as tacrolimus, and some are only available to be prepared in tertiary center pharmacies as Cyclosporine A with higher concentrations.

Effectiveness of Subconjunctival Cyclosporine in Treatment of Acute Allergic Conjunctivitis in a Rat-Model

Background

Eye allergy is widely spread worldwide. The treatment includes topical anti-histamines, steroids and non-steroidal drugs. Steroids are the first choice by many ophthalmologists, but unfortunately they may cause serious side effects. Cyclosporine A (CsA) is an immunomodulator drug that can improve eye allergy and reduce the need for steroids; however, topical preparation of CsA is difficult because of the lipophilic nature of the drug.

Methods

An experimental study included 16 rats with induced allergy were divided into 2 groups. Group 1: allergic non-treated (6 rats), and Group 2: allergic treated with 0.5 mL subconjunctival CsA 1% (10 rats). Half of each group was sacrificed at 24 hrs and the other half at 1 week. Conjunctival hyperemia and eosinophilic cell count were assessed at each time.

Results

Group 2 (CsA treated) showed significantly lower hyperemia score and eosinophilic count at both 24 hrs and 1 week. No ocular complications were noted.

Conclusion

Subconjunctival CsA was safe and effective in treating ocular allergy through improving conjunctival hyperemia and reducing eosinophilic cell count with no significant ocular side effects.

Aqueous deficiency is a contributor to evaporation-related dry eye disease

Dry eye disease aetiologies can be classified dichotomously into aqueous deficient and evaporative types although many cases involve combinations of both. Differential diagnosis can be confounded by some features of dry eye disease being common to both aetiologies. For example, short tear break-up times are prime diagnostic findings of tear instability due to lipid and/or mucin deficiencies, but thin tear layers in aqueous deficient eyes also shorten tear break-up times, even at normal range rates of evaporation in eyes without lipid and/or mucin deficiencies. Because tear instability and short tear film break-up times due to thin tear layers can be independent of lipid and/or mucin deficiency, aqueous deficiency can be another form of evaporation-related dry eye. Conversely, tear layers which are thickened by punctal occlusion can be less susceptible to tear break-up. An inflamed lacrimal gland producing reduced quantities of warmer tears can be a basis for thin tear layers and tear instability demonstrated by shorter tear break-up times. Commonly used clinical tests for aqueous deficiency can be unreliable and less sensitive. Consequently, failure to detect or confirm aqueous deficiency as a contributor to short tear break-up times could result in too much weight being given to a diagnosis of meibomian gland deficiency. Less successful treatment outcomes may be a consequence of failing to detect aqueous deficiency. Refining disease classification by considering aqueous deficiency as a contributor to, or even a form of evaporation-related dry eye, could be the basis for more comprehensive and appropriate treatment strategies. For example, some treatment methods for evaporation-related dry eye might be appropriate for aqueous and mucin-deficient as well as lipid-deficient dry eyes. Anti-inflammatory treatment for the lacrimal gland as well as the conjunctiva, may result in increased aqueous production, reduced tear temperature, tear instability and evaporation rates as well as lower osmolarity.

Cyclosporine A eyedrops with self-nanoemulsifying drug delivery systems have improved physicochemical properties and efficacy against dry eye disease in a murine dry eye model

PURPOSE

We aimed to compare the physicochemical properties and in vivo efficacy of commercially available nanoemulsion cyclosporine A (CsA) eyedrops in benzalkonium chloride (BAC)-induced dry eye disease (DED).

METHODS

Particle size analysis was performed on conventional 0.05% CsA (Restasis, C-CsA) and two new types of 0.05% CsA eyedrops based on a self-nanoemulsifying drug delivery system (SNEDDS, SNEDDS-N and -T). Turbidometry, pH measurements and instability indices of each CsA solution were measured. DED was induced with BAC, and animals were treated with vehicle or CsA preparations. Tear volume and fluorescein staining scores were evaluated on days 7 and 14. Eyes were enucleated and subjected to IHC, TUNEL staining, periodic acid-Schiff (PAS) staining, real-time PCR and western blotting.

RESULTS

Both SNEDDSs had lower and more uniform particle size distribution than C-CsA, and a similar optical density to phosphate-buffered saline and stable pH, in contrast to the high turbidity and unstable pH of C-CsA. Aqueous tear volume and fluorescein staining scores were improved in C-CsA- and SNEDDS-treated mice. Numbers of PAS-positive goblet cells and levels of inflammatory mediators were decreased by both C-CsA and SNEDDS, although SNEDDS resolved inflammation more effectively than C-CsA.

CONCLUSIONS

Cyclosporine A eyedrops with SNEDDS have improved physicochemical properties and treatment efficacy in BAC-induced DED.

Three Dimensional Culture of Potential Epithelial Progenitor Cells in Human Lacrimal Gland

Purpose

We investigate human lacrimal gland tissue to determine the presence of progenitor cells in this adult human tissue.

Methods

Six human lacrimal gland tissues from donors were collected and stored immediately in the culture medium at 4°C until the next procedure. One part of the lacrimal gland tissue was prepared for immunofluorescence staining and the other part was prepared for primary cell culture. Immunofluorescence analysis was conducted to evaluate cultured lacrimal epithelial phenotype and progenitor cell markers for five passages. Real-time polymerase chain reaction (PCR) was performed to assess proliferation markers in the different passages. Three-dimensional culture and PCR were conducted to determine the differentiation potential of cultured human lacrimal gland cells.

Results

Human lacrimal gland tissue expressed a number of epithelial progenitor cell markers. Precursor cell markers C-Kit, K15, Nestin, and P63 were observed in lacrimal gland tissues. Lacrimal gland epithelial cells were cultured successfully and passaged to P5. The cultured lacrimal gland epithelial cells were positive for pan-cytokeratin (PCK), AQP5, Rab3D, ABCB5, C-kit, K15, Ki67, and P63. Human lacrimal gland cells could form spheroids in vitro and then grow into mini-gland-like structures. PCR results showed proliferation and differentiation capability of those cultured cells.

Conclusions

Human lacrimal gland tissues contain precursor marker-positive cells and marker expression also was detected in ex vivo cultured cells, which showed differentiation capability.

Translational Relevance

Future studies of differentiation in human lacrimal gland tissue may aid in developing stem cell-based therapies for dry eye disease.

Solubilization of Cyclosporine in Topical Ophthalmic Formulations: Preformulation Risk Assessment on a New Solid Form

Owing to the discovery of a less soluble crystalline form (form 2) of cyclosporine (CsA), risks in solubility and physical stability of these formulations need to be revisited. This work focused on understanding the solubility behavior of various CsA forms in different media, including water, castor oil, and selected cosolvent micellar systems. In water, form 2 was approximately 8-9 times less soluble than form 1 (aka. tetragonal dihydrate). In neat nonaqueous solvent, for example, castor oil, form 3 (aka. orthorhombic hydrate) was found to have the lowest solubility and therefore the most stable form. In addition, the solubility-temperature relationship of CsA is complex and solvent-dependent. In aqueous vehicles, retrograde temperature dependence of solubility was observed in aqueous vehicles, that is, the solubility of CsA decreased with temperature, which was attributed to the effect of temperature on the strength of hydrogen bonding interactions; conversely, the solubility of CsA increased with temperature in nonaqueous solvents. In addition, the solubility of these CsA forms was very sensitive to temperature. Temperature-dependent form transformation was also observed in the media studied, with faster form conversion occurring at elevated temperatures. These studies provided key information to support the risk assessment for topical ophthalmic formulation development of CsA.

Dry eye disease immune responses and topical therapy

There is accumulating evidence that inflammation is one of the key components of dry eye because chronic ocular surface inflammation can be both a result as well as an initiator of dry eye. The need for continuing anti-inflammatory therapy may be determined in part by the extent that non-modifiable factors such as gender and age-related aqueous or lipid or mucus production deficiencies contribute to its chronicity. This perspective examines how the need for increased dosage of a topical anti-inflammatory drug may be determined by the degree of difficulty that a topically administered drug has in accessing different sites of tear deficiency and associated inflammation.

Emerging targets of inflammation and tear secretion in dry eye disease

The underlying mechanisms of dry eye are thought to be part of a vicious circle involving a hyperosmolarity-triggered inflammatory cascade, resulting in loss of goblet cells and glycocalyx mucin and observed corneal and conjunctival epithelial cell damage. This damage leads to increased tear film instability, further hyperosmolarity and hence perpetuating of a vicious circle. The aim of dry eye management is to restore the homeostasis of the tear film and break the perpetuation of this vicious circle. Despite the plethora of treatment options available, many of these are largely palliative, short-lived and require repeated instillations. Two emerging areas in dry eye therapy aim to promote tear secretion and to safely manage dry eye-associated inflammation and are the focus of this review.

The Efficiency of Cyclosporine A-Eluting Contact Lenses for the Treatment of Dry Eye

PURPOSE

To investigate the efficacy and safety of a new cyclosporine A (CsA) delivery system using contact lenses (CLs) for the treatment of experimental dry eye (EDE).

METHODS

CsA-laden porous carriers and CsA-eluting CLs were fabricated using the supercritical fluid technique. The release of CsA from carriers and CLs was investigated using high-performance liquid chromatography. The CsA concentrations in the cornea, conjunctiva, and crystalline lens of rabbits were measured. Dry eye was induced using 0.1% benzalkonium chloride in rabbits, which were subdivided into the normal, EDE, balanced salt solution (BSS), 0.05% CsA, hydrogel CL, or CsA-CL groups. Tear volume, tear film break-up time (TBUT), and corneal staining scores were measured at 1 and 2 weeks after treatment. Periodic acid-Schiff staining for the evaluation of conjunctival goblet cell density was performed at 2 weeks. Interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and interferon-γ levels in the conjunctiva were measured using enzyme-linked immune-sorbent assay.

RESULTS

The porous carrier showed the release of drug. CsA-eluting CLs showed initial burst and sustained release of CsA until 48 h. The concentration of CsA elevated in the cornea, conjunctiva, and lens until 48 h after application of CsA-CLs. The CsA-CL group showed significantly higher tear volume, TBUT, and lower corneal staining scores compared to the other groups (p < 0.05). Goblet cell density was significantly higher in the CsA-CL group compared to the other groups. The CsA-CLs group showed a lower level of IL-1β than the BSS and soft CL groups (p < 0.01), and a lower level of IFN-γ than the other groups (all p < 0.01).

CONCLUSIONS

The newly designed CsA-eluting CLs released drug continuously and showed good penetration in the eye. In addition, the use of CsA-eluting CLs improved clinical parameters and conjunctival goblet cell density and decreased inflammatory cytokines.

Method for selective quantification of immune and inflammatory cells in the cornea using flow cytometry

The cornea serves as a protective surface against the environment (i.e., allergens, pollutants, desiccation and microorganisms) and promotes vision, made possible by corneal transparency. This protocol describes corneal preparation for flow cytometry to assess cells localized in the cornea. Our model details the process, from determining how many corneas are needed in the experiment to corneal excision to digestion and staining of the cornea cells. The simplicity of the model allows for systematic analysis of different corneal mechanisms of immunity, inflammation, angiogenesis and wound healing. In corneal transplantation, residential immune and inflammatory cells are key to the mechanisms that underlie angiogenesis, opacity, and graft rejection. In addition, this model can also elucidate cellular mechanisms mediating corneal graft outcomes and wound healing. Lastly, this model can be used to analyze the efficacy of new medications such as instillation and subconjunctival injections and assess the potential of therapeutic molecules to enhance graft survival and wound healing in vivo.

Improving the topical ocular pharmacokinetics of lyophilized cyclosporine A-loaded micelles: formulation, in vitro and in vivo studies

Dry eye syndrome (DES) is one of the most common disorders of the eye for which combined treatment includes modification of the ocular environment and pathogenic therapies. Cyclosporine A (CsA), a immunosuppressive agent, has been demonstrated to be effective for the treatment of DES but is limited clinically by its low ocular bioavailability due to poor water solubility. In this paper, methoxy poly (ethylene glycol)-poly (lactide) polymer (mPEG-PLA) micelles were investigated as alternative vehicles for the solubilization and delivery of CsA to the eye. The in vitro stability indicated that CsA-loaded micellar lyophilized powder was stable for at least 3 months and the release profile showed a sustained release manner of CsA from micelles physically. In vivo ocular distribution studies demonstrated that the micellar formulations exhibited a 4.5-fold increase in retention effect at eyes compared with 0.05% CsA emulsion. In addition, the in vivo pharmacokinetics profile showed that the CsA-loaded micelles could enhance the retention time, achieving longer effect toward the DES. These studies proposed an effective micelle formulation as a novel ocular drug delivery system to improve solubility and bioavailability of ophthalmic CsA-controlled delivery.

Advancements in Host-Based Interventions for Influenza Treatment

Influenza is a major acute respiratory infection that causes mortality and morbidity worldwide. Two classes of conventional antivirals, M2 ion channel blockers and neuraminidase inhibitors, are mainstays in managing influenza disease to lessen symptoms while minimizing hospitalization and death in patients with severe influenza. However, the development of viral resistance to both drug classes has become a major public health concern. Vaccines are prophylaxis mainstays but are limited in efficacy due to the difficulty in matching predicted dominant viral strains to circulating strains. As such, other potential interventions are being explored. Since viruses rely on host cellular functions to replicate, recent therapeutic developments focus on targeting host factors involved in virus replication. Besides controlling virus replication, potential targets for drug development include controlling virus-induced host immune responses such as the recently suggested involvement of innate lymphoid cells and NADPH oxidases in influenza virus pathogenesis and immune cell metabolism. In this review, we will discuss the advancements in novel host-based interventions for treating influenza disease.

Ocular irritation and cyclosporine A distribution in the eye tissues after administration of Solid Lipid Microparticles in the rabbit model

The aim of this study was to investigate the in vivo effect of Solid Lipid Microparticles (SLM), proposed for topical ocular administration of cyclosporine, on the rabbit eye. SLM carrier is an aqueous dispersion of lipid microparticles (20% w/w) with a size up to 15 μm. Cyclosporine was dissolved in the formulation in the concentration of 0.5 or 2.0% (w/w). Ocular tolerance of microsphere dispersion was assessed in rabbit model by the Draize eye test (SLM was compared with emulsion and oily solution), and cyclosporine distribution in ocular tissues was evaluated after multiple application of tested formulations (SLM dispersions, emulsions and oily solution) for 7 days. Good tolerance of cyclosporine-SLM formulation was demonstrated in the rabbit model. Concentration of cyclosporine in the precorneal tissues, such as cornea and conjunctiva, was much higher than the therapeutic value (8.4 ng/mg and 3.2 ng/mg, respectively). After SLM administration, the cyclosporine concentrations determined in the anterior ocular tissues, were also significantly higher compared to those obtained after the application of other tested carriers (emulsions and oily solution). The obtained results prove that the recognized SLM dispersions are safe formulations for ophthalmic use. It can be concluded that lipid microparticles are highly promising for an efficient ophthalmic drug delivery, when compared to other conventional dosage forms.