Exploration of efficacy and mechanism of 0.05% cyclosporine eye drops (II) monotherapy in allergic conjunctivitis-associated dry eye.

PURPOSE: To explore the efficacy and relevant mechanism of 0.05% cyclosporine A (CsA) eye drops (II) monotherapy in patients with allergic conjunctivitis-associated dry eye (ACDE). METHODS: Prospective, randomized, controlled study. Fifty-three patients with mild-to-moderate ACDE were randomly assigned to two groups. The CsA group received 0.05% CsA eye drops (II) monotherapy four times daily. The control group received 0.1% olopatadine twice daily combined with 0.1% preservative-free artificial tears four times daily. Clinical symptoms and signs, tear total IgE, and lymphotoxin-α (LT-α) concentrations were assessed at pre- and post-treatment days 7, 30, and 60. And we further measured six tear cytokines levels using a microsphere-based immunoassay. RESULTS: The CsA group showed significant improvement in symptoms (Ocular Surface Disease Index and itching scores) and signs (conjunctival hyperaemia, conjunctival oedema, conjunctival papillae, tear break-up time (TBUT), corneal fluorescein staining, and goblet cell density) at each follow-up period compared to pre-treatment (all P < 0.050). And its improvement in itching scores (P7th < 0.001, P30th = 0.039, and P60th = 0.031) and TBUT (P7th = 0.009, P30th = 0.003, and P60th = 0.005) was more significant than the control group at all follow-up periods. The tear total IgE, interleukin (IL)-5, IL-6, periostin, eotaxin-3, and MMP-9 levels significantly decreased in the CsA group at day 60 after treatment (all P < 0.050). And the changed values in tear total IgE were positively correlated with the change in itching scores. CONCLUSIONS: 0.05% CsA eye drops (II) monotherapy can rapidly improve the symptoms and signs, especially in ocular itching and TBUT, in patients with ACDE. And its efficacy is superior to 0.1% olopatadine combined with artificial tears. Moreover, CsA downregulates the expression levels of tear inflammatory cytokines, including tear total IgE, IL-5, IL-6, periostin, eotaxin-3, and MMP-9. Among that, the reduction in tear total IgE levels may reflect the improvement of ocular itching.

A Quality by Design and green LC technique for the determination of mast cell stabilizer and histamine receptor antagonist (Olopatadine HCl) in multiple formulations.

Mast cell stabilizer and histamine receptor antagonist olopatadine hydrochloride (OPT) assay method predicated on LC have been established for the analysis in multiple formulations. The current method dealt with ophthalmic solution, nasal spray, and tablet formulation products. The isocratic chromatography method was optimized and validated with a Boston green C8 column (150 × 4.6 mm, 5 µm i.d.). Sodium dihydrogen phosphate buffer (pH 3.5) with acetonitrile in the ratio of 75:25 (v/v) was used as a mobile phase at a flow rate of 1.0 mL min-1 and at the column temperature of 30°C, and the detection was done at 299 nm. The method was validated as per International Council for Harmonisation (ICH) guidelines and United States Pharmacopoeia (USP). The accuracy results ranged from 99.9 to 100.7%, % relative standard deviation (RSD) from the precision was 0.5, and correlation coefficient from the linearity experiment was > 0.999. Solution stability was established for 24 h at room temperature and refrigerator conditions, and it was found that the solutions were stable. Using quality by design-based experiment designs, critical quality attributes were studied and it was found that the method was robust. In all the forced degradation studies peak purity was passed, and no interference was found at the retention time of the active component. The method validation data demonstrated that the developed method is linear, precise, accurate, specific, robust, and stable for the determination of OPT from multiple formulations. Analytical eco-scale tool, Green Analytical Procedure Index (GAPI) tool, and the National Environmental Method Index (NEMI) were used to evaluate the greenness of the method, and the analytical eco-score of 77 for the presented method was found to be excellent.

Efficacy and safety of twice-daily olopatadine-mometasone combination nasal spray (GSP301) in the treatment of allergic rhinitis: a systematic review and meta-analysis.

PURPOSE: GSP301 is a fixed-dose combination of olopatadine hydrochloride (antihistamine) and mometasone furoate (corticosteroid). This meta-analysis aims to evaluate the efficacy and safety of GSP301 in the treatment of allergic rhinitis. METHODS: A systematic review and meta-analysis were conducted. The data were collected from PubMed, Cochrane Central Register of Controlled Trials and Embase databases till June 2021. In patients with AR, short-term (2/6 weeks) and long-term (52 weeks) effects of GSP301 were assessed. Average morning and evening 12-h reflective total nasal symptom score (rTNSS), instantaneous total nasal symptom score (iTNSS), reflective total ocular symptom score (rTOSS), instantaneous total ocular symptom score(iTOSS), Physician-assessed nasal symptom score (PNSS), rhinoconjunctivitis quality of life (RQLQ), rhinitis control assessment test (RCAT) and adverse events (AEs) were measured. RESULTS: Five randomized controlled trials were included. GSP301 showed greatly improvement in rTNSS (MD = - 0.99; [95% CI - 1.19 to - 0.79]; P < 0.01; I2 = 0), iTNSS (MD = - 1.05; [95% CI - 1.44 to - 0.67]; P < 0.01; I2 > 50%), rTOSS (MD = - 0.50; [95% CI - 0.72 to - 0.29]; P < 0.01; I2 = 0), iTOSS (MD = - 0.64; [95% CI - 1.02 to - 0.26]; P < 0.01; I2 > 50%), PNSS (MD = - 1.01; [95% CI - 1.32 to - 0.69]; P < 0.01; I2 = 22.13%), RQLQ (MD = - 0.43; [95% CI - 0.57 to - 0.30]; P < 0.01; I2 = 0%) and RCAT (MD = 1.94; [95% CI 1.43-2.45]; P < 0.01; I2 = 0%) in the short term. No statistical difference was observed in the outcome of long-term PNSS, RQLQ and RCAT. CONCLUSION: GSP301 is a safe and well-tolerated medication. It showed short-term benefits for seasonal and perennial AR, but may not help to improve patients' quality of life and rhinitis control in the long run.

Novel Polyvinyl Pyrrolidone-Loaded Olopatadine HCl-Laden Doughnut Contact Lens to Treat Allergic Conjunctivitis.

Olopatadine HCl is an antiallergic drug used for the management of allergic conjunctivitis. Currently, it is delivered via eye drop solution, which is highly inefficient due to low bioavailability. Silicone contact lenses can be used to sustain the release of ophthalmic drugs. However, the presence of drug alters the optical transmittance and physical properties of the contact lens. The objective was to design a novel polyvinyl pyrrolidone (PVP)-coated olopatadine-ethyl cellulose microparticles-laden doughnut contact lens to sustained ocular delivery with limited alteration to the optical and swelling properties of the contact lens. The doughnut was implanted within the periphery of the lens using modified casting technique. Olopatadine HCl was loaded by soaking (SM-OL), direct loading (DL-OL), and doughnut casting method (DNT-OL). PVP (comfort agent) was loaded on the surface of contact lens for all the batches via novel curing technique. The in vitro olopatadine HCl release data of SM-OL (up to 48-72 h) and DL-OL batches (up to 72 h) showed high burst release, whereas DNT-OL batch showed sustained release up to 120 h without significant (p > 0.05) alteration in the optical and swelling properties of contact lens. All the batches showed sustained release of PVP up to 120 h. The in vivo studies in the rabbit tear fluid showed improvement in the olopatadine HCl and PVP retention time in comparison to eye drop solution. The PVP-loaded DNT-OL-500 lens showed tear stabilization (comfort wear) in Schirmer strip test (rabbits) with no protein adherence in comparison to DNT-OL-500 lens without PVP. The study demonstrated the successful delivery of olopatadine HCl and PVP-K30 from the doughnut contact lens for the extended period with limited alteration to the optical and swelling properties of contact lens.

Comparison of cytotoxicities and anti-allergic effects of topical ocular dual-action anti-allergic agents.

BACKGROUND: To investigate the cytotoxicities of the topical ocular dual-action anti-allergic agents (alcaftadine 0.25%, bepotastine besilate 1.5%, and olopatadine HCL 0.1%) on human corneal epithelial cells (HCECs) and their anti-allergic effects on cultured conjunctival epithelial cells. METHODS: A Methylthiazolyltetrazolium(MTT)-based calorimetric assay was used to assess cytotoxicities using HCECs at concentrations of 10, 20 or 30% for exposure durations of 30 min, 1 h, 2 h, 12 h or 24 h. Cellular morphologies were evaluated by inverted phase-contrast and electron microscopy. Wound widths were measured 2 h, 18 h, or 24 h after confluent HCECs monolayers were scratched. Realtime PCR was used to quantify anti-allergic effects on cultured human conjunctival cells, in which allergic reactions were induced by treating them with Aspergillus antigen. RESULTS: Cell viabilities decreased in time- and concentration-dependent manners. Cells were detached from dishes and showed microvilli loss, cytoplasmic vacuoles, and nuclear condensation when exposed to antiallergic agents; alcaftadine was found to be least cytotoxic. Alcaftadine treated HCECs monolayers showed the best wound healing followed by bepotastine and olopatadine (p < 0.0001). All agents significantly reduced the gene expressions of allergic cytokines (IL-5, IL-25, eotaxin, thymus and activation-regulated chemokine, and thymic stromal lymphopoietin) and alcaftadine had the greatest effect (p < 0.0001 in all cases). CONCLUSIONS: Alcaftadine seems to have less side effects and better therapeutic effects than the other two anti-allergic agents tested. It may be more beneficial to use less toxic agents for patients with ocular surface risk factors or presumed symptoms of toxicity.

Development and in vitro/in vivo evaluation of thermo-sensitive in situ gelling systems for ocular allergy

Ocular allergy is one of the most common disorders of the eye surface. Following diagnosis this condition is typically treated with preparations containing antihistamines. However, anatomy of the eye and its natural protective mechanisms create challenges for ocular drug delivery. Rapid elimination of antihistamine substances due to short residency times following application can lead to insufficient treatment of ocular allergies. With this in mind, the aim of this study was to prepare a controlled ocular delivery system to extend the retention time of olopatadine hydrochloride (OLO) and in doing so to reduce the need for frequent application. We developed extended-release ocular in situ gelling systems for which in vivo retention times were determined in sheep following in vitro characterization and cytotoxicity studies. In vivo results were then compared to commercially available Patanol eye drops. the transparent gels formulated using appropriate amounts of polymers and having longer ocular retention times appear to be a viable alternative to commercially available eye drops.

Olopatadine enhances recovery of alkali-induced corneal injury in rats.

AIMS: The alkali-induced corneal injury is an ocular emergency that required an immediate and effective management to preserve the normal corneal functions and transparency. Olopatadine is a fast, topically-effective anti-allergic drug, which exhibited potent anti-inflammatory and anti-angiogenic abilities in different allergic animals' models. Therefore, this study aimed to evaluate the therapeutic effect of olopatadine on alkali-induced corneal injury in rats. MATERIALS AND METHODS: Corneal alkali injury (CI) induced in the right eyes of an eight-week-old male Wister rats, by application of 3 mm diameter filter-papers, soaked for 10 s in 1 N-NaOH, to the right eyes' corneal centers for 30 s, afterward, the filter paper removed, and the rat right eye rinsed with 20 ml normal saline. For treatment of CI, either 0.2% or 0.77% olopatadine applied topically daily for 14 days, starting immediately after the induction of CI. KEY FINDINGS: Olopatadine, in the present work, effectively and dose-dependently enhanced the corneal healing after alkali application, with significant reduction of the corneal opacity and neovascularization scores, besides, it suppressed the augmented corneal IL-1ß, VEGF, caspase-3 levels, and nuclear NF-κB immunohistochemical expression, meanwhile it abrogated the corneal histopathological changes, induced by alkali application. SIGNIFICANCE: Olopatadine appears to be a potential treatment option for alkali-induced corneal injury.

[Eye lid hygiene in chronic allergic blepharoconjunctivitis patients before laser refractive surgery]. / Gigiena vek v podgotovke k lazernoi refraktsionnoi khirurgii.

AIM: To evaluate the effectiveness of eyelid hygiene in patients with chronic allergic blepharoconjunctivitis (ABC) as a part of their preparation for laser refractive surgery. MATERIAL AND METHODS: The study involved 32 patients (12 males and 20 females aged 25-42 years) with refractive errors, namely, compound myopic astigmatism (23 patients) and hyperopic astigmatism (9 patients) suffering from chronic ABC and secondary dry eye syndrome (DES). All the patients initially received a standard treatment for ABC and DES, that is olopatodin hydrochloride instillations - 1 mg/ml 2 times daily, preservative-free hyaluronic acid preparation - 1 mg/ml 3 times daily, and polyacrylic acid and dexpanthenol gel at night for one month. The scheme, however, appeared not effective enough. Hence, the patients were prescribed eyelid hygiene (Blepharolotion or Blepharosalfetka plus Blepharogel-1 2 times daily) to relive meibomian gland dysfunction (MGD). They also underwent a conventional ophthalmic examination, allergy tests, evaluation of ABC and DES signs and symptoms, tear film break-up time test, Schirmer's test, meibomian glands evaluation, optical coherence tomography with meniscometry, xerosis index evaluation, and lissamine green staining for lid wiper epitheliopathy. RESULTS: At the beginning of the study signs and symptoms of MGD-associated DES were predominant in all patients. Chronic ABC signs were mild. In 2-3 months, meibomian gland function and tear film break-up time improved significantly in most patients, while xerosis index decreased and lid wiper epitheliopathy resolved. Laser refractive surgery (LASIK) was performed in 81.25% of patients, all of whom were satisfied with the results. CONCLUSION: Inclusion of eyelid hygiene into preoperative management of patients with chronic ABC and DES allows to achieve optimum conditions for laser refractive surgery in most cases.

Biomimetic contact lenses eluting olopatadine for allergic conjunctivitis.

UNLABELLED: Combination of the ability of contact lenses (CLs) to act as a physical barrier against airborne antigen and to serve as a sustained depot of antihistaminic drugs may improve the efficiency of treatments of some ocular allergic diseases. The aim of this work was to develop CLs that exhibit affinity to olopatadine by mimicking the composition of the natural H1-receptor for which olopatadine behaves as a selective antagonist. Functional monomers that match the chemical groups of the receptor and application of the molecular imprinting technology led to hydrogels able to load high amounts of olopatadine and to sustain the release once in contact with lachrymal fluid. Optimized hydrogels prepared with acrylic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid and benzylmethacrylate as functional monomers provided in few hours olopatadine concentrations similar to those of commercially available eye drops but the levels could be sustained for a whole day, demonstrating their efficacy. Olopatadine-loaded CLs successfully passed the HET-CAM test of ocular irritancy and showed good compatibility with mast cells. They were able to inhibit the release of histamine and TNF-α from sensitized mast cells, proving their potential application in preventing and treating allergic conjunctivitis. STATEMENT OF SIGNIFICANCE: Contact lenses (CLs) with affinity for antiallergic drugs may constitute an advantageous alternative to eye drops in management of ocular allergies for both contact lens wearers and patients who eventually use neutral CLs as therapeutic platforms. The present work represents a step forward in the state of the art of drug-CL combo products by (i) mimicking the composition of the human receptor of the drug, (ii) exploring combinations of functional monomers that include a monomer (2-acrylamido-2-methyl-1-propanesulfonic acid; AMPSA) with a strong acid group (pKa<4) able to enhance the interaction of the network with olopatadine in the saline environment of the lachrymal fluid, and (iii) analysing in detail the antihistamic effects provided by olopatadine released from the CLs on sensitized mast cells.

Treatment with olopatadine and naphazoline hydrochloride reduces allergic conjunctivitis in mice through alterations in inflammation, NGF and VEGF.

The aim of the current study was to investigate whether olopatadine and naphazoline hydrochloride reduce allergic conjunctivitis in mice through alterations in inflammation, NGF and VEGF. An allergic conjunctivitis mouse model was established using histamine or an antigen (ovalbumin), following which mice were treated with 1% olopatadine solution and/or 0.2 mg/ml of naphazoline hydrochloride. Histamine or antigen­induced conjunctival vascular hyperpermeability was examined and the levels of inflammatory factors, cytokines, IgE, GMCSF and NGF were analyzed using ELISA in antigen­induced conjunctival vascular hyperpermeability mice. In addition, VEGF protein expression was measured using western blotting in antigen­induced mice. The results indicated that olopatadine and naphazoline hydrochloride significantly suppressed conjunctival dye leakage in mice with histamine or antigen­induced conjunctival vascular hyperpermeability. In addition, treatment with olopatadine and naphazoline hydrochloride was able to reduce the levels of inflammatory factors (TNF­α, IL­1ß and IL­6), cytokines (IFN­Î³ and IL­4), IgE, GMCSF, and NGF in antigen­induced conjunctival vascular hyperpermeability mice. The protein expression levels of VEGF in antigen­induced conjunctival vascular hyperpermeability mice were reduced following treatment with olopatadine and naphazoline hydrochloride. These results suggest that treatment with olopatadine and naphazoline hydrochloride reduces conjunctivitis in mice via effects on inflammation, NGF and VEGF.

In vitro effects of preserved and unpreserved anti-allergic drugs on human corneal epithelial cells.

PURPOSE: Treatment with topical eye drops for long-standing ocular diseases like allergy can induce detrimental side effects. The purpose of this study was to investigate in vitro cytotoxicity of commercially preserved and unpreserved anti-allergic eye drops on the viability and barrier function of monolayer and stratified human corneal-limbal epithelial cells. METHODS: Cells were treated with unpreserved ketotifen solution, benzalkonium chloride (BAC)-containing anti-allergic drugs (ketotifen, olopatadine, levocabastine) as well as BAC alone. 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to determine cell viability. Effects of compounds on barrier function were analyzed measuring transepithelial electrical resistance (TEER) to determine paracellular permeability and rose bengal assays to evaluate transcellular barrier formation. RESULTS: The BAC-preserved anti-allergic formulations and BAC alone significantly reduced cell viability, monolayer cultures being more sensitive to damage by these solutions. Unpreserved ketotifen induced the least diminution in cell viability. The extent of decrease of cell viability was clearly dependent of BAC presence, but it was also affected by the different types of drugs when the concentration of BAC was low and the short time of exposure. Treatment with BAC-containing anti-allergic drugs and BAC alone resulted in increased paracellular permeability and loss of transcellular barrier function as indicated by TEER measurement and rose bengal assays. CONCLUSIONS: The presence of the preservative BAC in anti-allergic eye drop formulations contributes importantly to the cytotoxic effects induced by these compounds. Stratified cell cultures seem to be a more relevant model for toxicity evaluation induced on the ocular surface epithelia than monolayer cultures.

Azelastine desensitization of transient receptor potential vanilloid 1: a potential mechanism explaining its therapeutic effect in nonallergic rhinitis.

BACKGROUND: Capsaicin, a prototypic transient receptor potential vanilloid 1 (TRPV1) agonist, has been shown to be more clinically effective in the treatment of nonallergic rhinitis (NAR) compared with other rhinitis subtypes. Azelastine has also been found to be clinically effective in the treatment of NAR but its mechanism(s) of action is still poorly elucidated. This study was designed to determine, using in vitro cell lines, whether topical therapies including azelastine have activity on TRPV1 ion channels similar to capsaicin. METHODS: The effects of capsaicin (1 µM), azelastine (30 µM), bepotastine (10 µM), olopatadine (10 µM), and fluticasone (200 µM) on TRPV1 channels using mice neuronal cells (Cath.a), as surrogates for submucosal sensory neurons, and human nasal epithelial cells (hNEC) were determined and compared. For azelastine, bepotastine, and capsaicin, which elicited an agonist effect on TRPV1, live cell [Ca(2+)] signaling in Cath.a cells and hNECs expressing TRPV1 were performed in the absence and presence of capsazepine at 10 µM (a TRPV1 antagonist) or using wild-type mouse embryonic fibroblasts (wtMEFs) that express TRPV1 ion channels and TRPV1 homozygous null mutant (TRPV1-/-) knockout MEF cells as controls to establish TRPV1 channel selectivity. As azelastine has previously been found clinically effective in NAR, additional experiments were performed to determine its ability to desensitize TRPV1 ion channels and its effect on regulating intracellular calcium homeostasis. RESULTS: Cath.a cells treated with azelastine, bepotastine, or capsaicin showed a significant increase in TRPV1-dependant (Ca(2+)) specific cytosolic fluorescence. Continuous treatment with azelastine or capsaicin resulted in desensitization of TRPV1 channels. In hNECs, azelastine stimulation resulted in Ca(2+) shifts from the cytosol to mitochondria and overexpression of hematopoietic cell-specific Lyn substrate 1-associated protein X1, which may thus be effective in cytosolic Ca(2+) homeostasis. CONCLUSION: Azelastine, similar to capsaicin, exhibits direct activity on TRPV1 ion channels that may represent a novel mechanistic pathway explaining its clinical efficacy in NAR.

Vernal keratoconjunctivitis: a severe allergic eye disease with remodeling changes.

Vernal keratoconjunctivitis (VKC) is an unusually severe sight-threatening allergic eye disease, occurring mainly in children. Conventional therapy for allergic conjunctivitis is generally not adequate for VKC. Pediatricians and allergists are often not familiar with the severe clinical symptoms and signs of VKC. As untreated VKC can lead to permanent visual loss, pediatric allergists should be aware of the management and therapeutic options for this disease to allow patients to enter clinical remission with the least side effects and sequelae. Children with VKC present with severe ocular symptoms, that is, severe eye itching and irritation, constant tearing, red eye, eye discharge, and photophobia. On examination, giant papillae are frequently observed on the upper tarsal conjunctiva (cobblestoning appearance), with some developing gelatinous infiltrations around the limbus surrounding the cornea (Horner-Trantas dot). Conjunctival injections are mostly severe with thick mucus ropy discharge. Eosinophils are the predominant cells found in the tears and eye discharge. Common therapies include topical antihistamines and dual-acting agents, such as lodoxamide and olopatadine. These are infrequently sufficient and topical corticosteroids are often required for the treatment of flare ups. Ocular surface remodeling leads to severe suffering and complications, such as corneal ulcers/scars. Other complications include side effects from chronic topical steroids use, such as increased intraocular pressure, glaucoma, cataract and infections. Alternative therapies for VKC include immunomodulators, such as cyclosporine A and tacrolimus. Surgery is reserved for those with complications and should be handled by ophthalmologists with special expertise. Newer research on the pathogenesis of VKC is reviewed in this article. Vernal keratoconjunctivitis is a very important allergic eye disease in children. Complications and remodeling changes are unique and can lead to blindness. Understanding of pathogenesis of VKC may lead to better therapy for these unfortunate patients.

Advantages of histamine H4 receptor antagonist usage with H1 receptor antagonist for the treatment of murine allergic contact dermatitis.

Histamine facilitates development of eczematous lesions in chronic allergic contact dermatitis. In addition to the well-known corticosteroid treatments, H1 receptor (H1R) antagonists also have been used. This study observed effects of histamine H4 receptor (H4R) antagonist usage with H1R antagonist in a murine chronic allergic contact dermatitis model, developed by repeated percutaneous challenge to the dorsal skin with 2,4,6-trinitro-1-chlorobenzene (TNCB). The H1R antagonist olopatadine hydrochloride and/or the H4R antagonist JNJ7777120 was then administered. Combination therapy was more effective than H1R antagonist monotherapy. Serum IgE and levels of interleukin (IL)-4, IL-5 and IL-6 (Th2 cytokines) in eczematous lesions decreased with combined therapy. Combined therapy with H1R and H4R antagonists counteracts the disadvantages of each as monotherapeutic agents and potentially represents a new strategy for the treatment of chronic allergic contact dermatitis.

The antagonism of histamine H1 and H4 receptors ameliorates chronic allergic dermatitis via anti-pruritic and anti-inflammatory effects in NC/Nga mice.

BACKGROUND: Although histamine H1 receptor (H1R) antagonists are commonly used to treat atopic dermatitis, the treatment is not always effective. The histamine H4 receptor (H4R) was recently described as important to the pruritus in dermatitis. Here, we investigated whether the combination of a H1R antagonist plus a H4R antagonist attenuates chronic dermatitis in NC/Nga mice. METHODS: Chronic dermatitis was developed by repeated challenges with picryl chloride on the dorsal back and ear lobes. The therapeutic effects of the H1R antagonist olopatadine and H4R antagonist JNJ7777120 on scratching and the severity of dermatitis were evaluated. In addition, the mechanisms responsible for the anti-allergic effects of H1R and/or H4R antagonism were examined using bone marrow-derived mast cells (BMMC) and keratinocytes. RESULTS: JNJ7777120 attenuated scratching behavior after a single administration and improved dermatitis, as assessed with clinical scores, pathology, and cytokine levels in skin lesions when administered repeatedly. These effects were augmented by combined treatment with olopatadine, having a similar therapeutic efficacy to prednisolone. JNJ7777120 inhibited dose-dependently the production of thymus and activation-regulated chemokine/CCL17 and macrophage-derived chemokine/CCL22 from antigen-stimulated BMMC. In addition, olopatadine reversed the histamine-induced reduction of semaphorin 3A mRNA in keratinocytes. CONCLUSION: Combined treatment with H1R and H4R antagonists may have a significant therapeutic effect on chronic dermatitis through the synergistic inhibition of pruritus and skin inflammation.

Intrastromal corneal ring segments for bilateral keratoconus in an 11-year-old boy.

UNLABELLED: We present the case of an 11-year-old boy who had bilateral implantation of intrastromal corneal ring segments for progressive keratoconus and poor vision. No intraoperative or postoperative complications were seen, and 1 year postoperatively, the patient maintained good spectacle-corrected vision. FINANCIAL DISCLOSURE: Neither author has a financial or proprietary interest in any material or method mentioned.

[Toxicity of topical ocular anti-allergic agents on human corneal epithelial cells in vitro].

OBJECTIVE: To investigate the cytotoxic effect of three kinds of topical ocular anti-allergic agent, including olopatadine 0.1% (A group), ketotifen fumarate 0.025% (B group) and pemirolast potassium 0.1% (C group), on cultured human corneal epithelial cells in vitro. METHODS: Primary human corneal epithelial cells were cultured with keratinocyte serum-free medium. The cells were exposed to three kinds of topical ocular anti-allergic agent for a period of 10 min, 30 min, 2 h, 6 h, 12 h and 24 h. Toxicity was examined in three ways. MTT assay was used to quantify cytotoxicity. Cell membrane permeability and intracellular esterase activity were analyzed with live-dead viability staining of fluorescent calcein-AM/ethidium homodimer. The morphologic analysis was performed by light and scanning electron microscopy. Statistical methods adopted one-way ANOVA (analysis of variance) and Student-Newman-Keuls q test between each group. The P-value of 0.05 was considered statistically significant. RESULTS: (1) Morphologic changes: The Findings under the light microscopy were demonstrated that cells became round or edematic and detached from dishes after exposure to topical ocular anti-allergic agent. The cellular damage was more severe with longer exposure time and increasing concentration. Likewise, the electron microscopy examination showed reduced microvilli with longer exposure time and increasing concentration. The cellular changes of 20.0% olopatadine 0.1% were reduced when compared to the other agents. (2) Live/dead viability/cytotoxicity assay: Ethidium homodimeric permeates damaged cell membranes and results in red fluorescence. These results indicated that cell membrane damage caused by 20.0% olopatadine 0.1% at 6, 12, 24 h was less than those of ketotifen fumarate 0.025% and pemirolast potassium 0.1%. The data of A group were (29.7 +/- 2.6)%, (36.9 +/- 3.2)%, (51.2 +/- 4.3)%, B group were (36.5 +/- 3.1)%, (48.5 +/- 4.3)%, (75.5 +/- 3.8)% and C group were (37.1 +/- 2.2)%, (52.7 +/- 3.4)%, (71.1 +/- 5.1)%, respectively. The q values of A to B group and A to C group at 6 h were 3.27, 4.31, respectively (P < 0.05). The green fluorescent staining of calcein-AM indicated intracellular esterase activity was decreased after incubation with increasing concentration and longer exposure time. There was no significantly different result between each group (P > 0.05). The proportion of green staining cell of A, B and C group at 24 h were 100.0% with 50.0% concentration and were (23.2 +/- 4.6)%, (29.5 +/- 5.2)%, (31.1 +/- 5.5)% respectively with 20.0% concentration (F = 1.97, P = 0.377). (3) MTT assay: The results of the three groups revealed cell viability decreased significantly with increasing concentration and longer exposure time at all the concentrations except 0.8%. MTT values for A, B and C group at the concentration of 20.0%, at 6 h were 0.429 +/- 0.028, 0.367 +/- 0.038, 0.379 +/- 0.012 and 4% at 24 h were 0.457 +/- 0.025, 0.401 +/- 0.008, 0.387 +/- 0.012, respectively. The data for olopatadine 0.1% were significantly improved over those of ketotifen fumarate 0.025% and pemirolast potassium 0.1%. The q value of A to B group, A to C group were 3.01, 3.77 (P < 0.05) at the concentration of 20.0%, 6 h and were 3.63, 4.11 (P < 0.05) at the concentration, 24 h. There were no statistical significant results at other concentrations. CONCLUSIONS: The topical ocular anti-allergic agent, olopatadine 0.1%, showed less toxic effects on human corneal epithelial cells compared to ketotifen fumarate 0.025% and pemirolast potassium 0.1%. Olopatadine 0.1% may offer a safer option to the corneal epithelium when used to treat allergic keratoconjunctivitis over an extended period of time.