Search Results (280)

Background: Antibody-drug conjugates (ADCs) have ushered in a new era of precision oncology by combining the targeting specificity of monoclonal antibodies with the potent cytotoxicity of chemotherapeutic drugs. However, the cellular and molecular mechanisms underlying their dose-limiting ocular toxicity remain unclear. Elahere™, the first FDA-approved ADC targeting folate receptor α (FRα), demonstrates remarkable efficacy in platinum-resistant ovarian cancer but causes keratitis and other ocular toxicities in some patients. Notably, FRα is not expressed in the corneal epithelium—the primary site of damage—highlighting the urgent need to elucidate its underlying mechanisms. The aim of this study was to identify the cell-type-specific molecular mechanisms underlying Elahere-induced ocular toxicity. Methods: Sprague-Dawley rats were treated with intravenous Elahere (20 mg/kg) or vehicle weekly for five weeks. Ocular toxicity was determined by clinical examination and histopathology. Corneal single-cell suspensions were analyzed using the BD Rhapsody single-cell RNA sequencing (scRNA-seq) platform. Bioinformatic analyses to characterize changes in corneal cell populations, gene expression, and signaling pathways included cell clustering, differential gene expression, pseudotime trajectory inference, and cell-cell interaction modeling. Results: scRNA-seq profiling of 47,606 corneal cells revealed significant damage to the ocular surface and corneal epithelia in the Elahere group. Twenty distinct cell types were identified. Elahere depleted myeloid immune cells; in particular, homeostatic gene expression was suppressed in phagocytic macrophages. Progenitor populations (limbal stem cells and basal cells) accumulated (e.g., a ~2.6-fold expansion of limbal stem cells), while terminally differentiated cells decreased in corneal epithelium, indicating differentiation blockade. Endothelial cells exhibited signs of injury and inflammation, including reduced angiogenic subtypes and heightened stress responses. Folate receptor alpha, the target of Elahere, was expressed in endothelial and stromal cells, potentially driving stromal cells toward a pro-fibrotic phenotype. Fc receptor genes were predominantly expressed in myeloid cells, suggesting a potential mechanism underlying their depletion. Conclusions: Elahere induces complex, multi-compartmental ocular toxicity characterized by initial perturbations in vascular endothelial and immune cell populations followed by the arrest of epithelial differentiation and stromal remodeling. These findings reveal a cascade of cellular disruptions and provide mechanistic insights into mitigating Elahere-associated ocular side effects. Full article

The healing issue is a central, not completely understood, problem in pharmacology, approached by many concepts. One of the most well-known is Robert’s and Szabo’s concept of cytoprotection, which holds innate cell (epithelial (Robert), endothelial (Szabo)) integrity, protection/maintenance/reestablishing in the stomach to be translated to other organ therapy (cytoprotection→organoprotection) via cytoprotection agent’s effect. Thereby, we defend stable gastric pentadecapeptide BPC 157 therapy, efficacy, pleiotropic beneficial effects along with high safety (LD1 not achieved) against Józwiak and collaborators’ review speculating its negative impact, speculation of angiogenesis toward tumorogenesis, increased NO and eNOS, toward damaging free radicals formation, and neurodegenerative diseases (Parkinson’s disease and Alzheimer’s disease). Contrarily, in wound healing and general healing capabilities as reviewed, as a cytoprotective agent, and native cytoprotection mediator, BPC 157 controls angiogenesis and the NO-system healing functions, and counteracts the pathological presentation of neurodegenerative diseases in acknowledged animal models (i.e., Parkinson’s disease and Alzheimer’s disease), and presents prominent anti-tumor potential, in vivo and in vitro. BPC 157 resolved cornea transparency maintenance, cornea healing “angiogenic privilege” (vs. angiogenesis/neovascularization/tumorogenesis), does not produce corneal neovascularization, but rather opposes it, and per Folkman’s concept, it demonstrates anti-tumor effect in vivo and in vitro. BPC 157 exhibits a distinctive effect on NO-level (increase vs. decrease), always combined with counteraction of free radicals formation, and in mice and rats, BPC 157 therapy counteracts Parkinson’s disease-like and Alzheimer’s disease-like disturbances. Thus, BPC 157 therapy means targeting angiogenesis and NO’s cytotoxic and damaging actions, but maintaining, promoting, or recovering their essential protective functions. Full article

Background/Objectives Conventional eye drops are the primary therapeutic option for ocular diseases; however, their clinical utility is hindered by several drawbacks, including limited bioavailability and suboptimal patient compliance. To overcome these challenges, we designed a sustained-release contact lens (CL) device loaded with tranilast (TRA) and determined whether the TRA-laden CL could provide sustained drug delivery to the lacrimal fluid and aqueous humor. Methods TRA nanocrystals were prepared using the bead-milling approach. Using three types of CLs (nonionic, anionic, and cationic), we prepared TRA-laden CLs by employing a combination of solid TRA nanocrystals and soaking methods under high-temperature and high-pressure conditions in an autoclave (the hThP method). Male Japanese albino rabbits (2–3 kg) were used to evaluate the CLs. Results Bead milling reduced the size of the solid TRA nanoparticles (STNs) to approximately 35–180 nm. The TRA-laden cationic CLs prepared using STNs and the hThP method contained a higher amount of TRA than those prepared using the corresponding conventional soaking method. The CLs prepared using the hThP method remained transparent after drug loading. Compared with nonionic and anionic CLs, cationic CLs had the highest drug-loading capacity and allowed for sustained drug release. Moreover, STNs were observed in the released TRA, with no corneal damage or light scattering detected in the rabbits’ eyes. TRA-laden cationic CLs prepared using the hThP method achieved sustained and higher drug delivery into the lacrimal fluid and aqueous humor than those prepared using the conventional soaking method. Conclusions Our findings suggest that TRA-laden cationic CLs prepared using STNs and the hThP method can overcome the challenges associated with the conventional soaking method, including low drug uptake and high burst release. Full article

Alkali burns to the cornea cause severe damage characterized by an intense inflammatory response driven by inflammatory cytokines, which orchestrate pathological processes, including neovascularization, fibrosis, apoptosis, abnormal cell proliferation, and disorganization of the extracellular matrix (ECM), often resulting in permanent vision impairment or loss. Rapamycin (RAPA), a well-known mTOR inhibitor with potent immunosuppressive activity and pleiotropic therapeutic effects, was investigated as a novel restorative modality for promoting corneal wound healing in a mouse model of alkali burn injury. Topical RAPA treatment significantly reduced clinical signs of inflammation and decreased the infiltration of F4/80⁺ macrophages and CD45⁺ leukocytes, along with suppressed expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-17A). RAPA also markedly downregulated angiogenic mediators, such as VEGF, and endothelial markers, like CD31, resulting in significant inhibition of neovascularization. Furthermore, it prevented fibrotic tissue formation and myofibroblast activation, as evidenced by reduced α-SMA levels, and attenuated pathological matrix remodeling through decreased MMP-9 expression. Notably, RAPA preserved epithelial barrier function by maintaining the tight junction protein ZO-1 and reduced both apoptotic cell death (TUNEL) and dysregulated proliferation (Ki67⁺), thereby preserving the functional and structural integrity of the cornea. In conclusion, RAPA represents a promising therapeutic candidate for managing severe corneal alkali burn injuries, with the potential to enhance corneal wound healing, minimize long-term complications, and protect visual function. Full article

Allergic rhinitis (hay fever) prevalence has increased in Australia. People with hay fever often experience many eye symptoms, especially itching. This study explores clinical correlations between tear IgE levels and ocular allergy signs in hay fever sufferers, focusing also on eyelid wiper friction damage from eye rubbing. In a cross-sectional study from November 2024 to January 2025, 16 individuals with self-reported hay fever and 17 healthy controls were recruited. Participants completed demographic and allergy-related questionnaires, including symptoms and quality of life assessments. Tear samples were analyzed for IgE and MMP-9 biomarkers. Ocular surface parameters-bulbar redness, palpebral roughness, and lid wiper epitheliopathy (LWE)-were graded. Corneal and conjunctival dendritic cells were also evaluated. Elevated tear IgE significantly correlated with self-reported hay fever, QUICK score, MiniRQLQ, eye rubbing frequency, and lower LWE grade. The hay fever group showed significantly higher LWE compared to healthy controls (p < 0.001), indicating frictional eyelid damage. ROC analysis of tear IgE yielded an AUC of 0.893 (cut-off 0.03 IU/mL; sensitivity 90%, specificity 85%). Tear IgE is a useful biomarker for ocular inflammation and may indicate friction-related eyelid damage in allergy sufferers. Incorporating LWE grading into clinical assessments of ocular allergy is recommended. Full article

Neurological disorders significantly affect ocular surface homeostasis, influencing parameters such as blink rate (BR), tear production, corneal nerve density, and sensitivity. This review summarizes recent findings on ocular surface alterations associated with neurological diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), Guillain-Barré syndrome (GBS), trigeminal neuralgia (TN), multiple sclerosis (MS), and Charcot–Marie–Tooth disease (CMT). Notably, ocular manifestations such as reduced BR, decreased tear break-up time (TBUT), impaired tear secretion, and corneal nerve fiber loss are consistently reported. In AD, elevated tear amyloid-beta and tau proteins emerge as promising biomarkers for early disease detection. PD patients frequently experience dry eye symptoms attributed to reduced BR and tear film instability. GBS is linked to lagophthalmos and corneal nerve impairment, potentially leading to severe ocular surface damage. TN demonstrates bilateral ocular surface dysfunction despite unilateral neuropathic symptoms. MS is associated with significant ocular surface alterations, reflecting broader neuroinflammatory and autonomic disturbances. Similarly, CMT patients show reduced corneal sensitivity and tear production, underscoring the systemic nature of neurological impacts. Awareness of these ocular manifestations is essential for improving patient care and guiding future research into ocular biomarkers and targeted therapies. Full article

Polyhexamethylene guanidine phosphate (PHMG-p), a widely used disinfectant component in household humidifiers, has been implicated in various health issues, including pulmonary toxicity. Many people use humidifiers to improve dry eye disease (DED). The current study was performed to elucidate the effect of PHMG-p on eye dryness in a rat model using metabolomics. Male Sprague Dawley rats were exposed to PHMG-p (0.1% and 0.3%) following a previously established DED induction model using scopolamine hydrobromide and desiccation stress. Ocular surface damage was assessed using corneal fluorescein staining, tear volume measurement, and tear break-up time (TBUT). Plasma and urine samples were analyzed using ¹H-NMR-based metabolomics to identify metabolic alterations associated with PHMG-P-p exposure and DED pathogenesis. PHMG-p exposure exacerbated DED symptoms, as evidenced by a significant reduction in tear volume, shorter TBUT, and increased corneal damage compared to the control group. Metabolomic profiling identified distinct metabolic changes in PHMG-p-exposed groups, including alterations in glutamate, glycine, citrate, and succinate metabolism. These metabolic changes correlated with increased levels of inflammatory cytokines such as IL-1β, IL-6, and TNF-α in the corneal and lacrimal gland tissues. Our findings suggest that PHMG-p exposure contributes to DED pathophysiology by inducing metabolic disturbances and inflammatory responses in the ocular surface. This study highlights the need for further investigation into the potential risks of PHMG-p exposure on ocular health and provides novel insights into the metabolic underpinnings of DED. Full article

Corneal nerve integrity is vital for maintaining ocular surface health and visual clarity, but damage from injury or disease can lead to pain, persistent epithelial defects, and even vision loss. A deeper understanding of how corneal nerves regenerate at the molecular level is key to developing therapies that restore both anatomical structure and function. In this review, we bring together current insights into the pathways that drive corneal nerve repair after injury. We outline the major signaling pathways that promote neuronal survival, axon extension, and nerve–epithelial interactions, along with evolving research around novel modulators that could improve repair outcomes. Although advances in imaging and molecular therapies have led to significant progress in promoting nerve regrowth, functional sensory recovery often lags. This gap in recovery emphasizes the need for research approaches that align anatomical restoration with sensory function. In this review, we aim to clarify the mechanisms underlying corneal nerve regeneration (and their intersections) and identify opportunities for improving patient outcomes. Full article

Radiation-induced keratoconjunctivitis sicca (KCS) is a significant late complication in dogs receiving radiation therapy for intranasal tumors, particularly with hypofractionated intensity-modulated radiation therapy (IMRT). This retrospective case-control study was performed to identify anatomical and dosimetric risk factors for KCS in 15 canine patients treated with IMRT delivered in 4–6 weekly fractions of 8 Gy. Orbital structures were retrospectively contoured, and dose–volume metrics (D50) were calculated. Receiver operating characteristic (ROC) curve analysis and odds ratios were used to evaluate the associations between radiation dose and KCS development. Six dogs (33%) developed KCS within three months post-treatment. Statistically significant dose differences were observed between affected and unaffected eyes for the eyeball, cornea, and retina. ROC analyses identified dose thresholds predictive of KCS: 13.8 Gy (eyeball), 14.9 Gy (cornea), and 17.0 Gy (retina), with the retina showing the highest odds ratio (28.33). To ensure clinical relevance, KCS was diagnosed based on decreased tear production combined with corneal damage to ensure clinical relevance. This study proposes dose thresholds for ocular structures that may guide treatment planning and reduce the risk of KCS in canine patients undergoing IMRT. Further prospective studies are warranted to validate these thresholds and explore mitigation strategies for high-risk cases. Full article

Background: Congenital insensitivity to pain with anhidrosis (CIPA) is a rare autosomal recessive syndrome caused by loss-of-function mutations in the Neurotrophic Tyrosine Kinase Receptor 1 gene, characterized by recurrent episodes of infections and unexplained fever, anhidrosis, absence of reactions to noxious stimuli, intellectual disability, self-mutilating behaviors, and damage to many body organs, including the eyes. Main text: We systematically searched the Medline/PubMed, Scopus, and Web of Science databases from their inception until March 2025 for papers describing the clinical manifestations of patients with CIPA. The inclusion criterion was papers reporting ocular manifestations of patients diagnosed with CIPA. We excluded non-English papers or those reporting ocular manifestations of patients diagnosed with syndromes other than CIPA. Also, we excluded review articles, clinical trials, gray literature, or any paper that did not report ocular manifestations of patients with CIPA or that reported patients with previous ocular surgeries. Out of 6243 studies, 28 were included in the final analysis, comprising 118 patients. The mean age was 7.37 years, and males represented 63.5% (n = 75). Of the patients, fifty-six had bilateral ocular manifestations. The most common ocular manifestations were the absence of corneal reflex in 56 patients (47.5%, bilateral in 56), whereas corneal ulcerations were the second most common manifestation in 46 patients (38.98%, bilateral in 8), followed by corneal opacity in 32 patients (27.11%, bilateral in 19). Topical lubricants, topical antibiotics, and lateral tarsorrhaphy were common management modalities for these patients. Absent corneal sensitivity, corneal ulcers, and corneal opacities, among other manifestations, are common ocular presentations in patients with CIPA. Conclusions: Self-mutilation, intellectual disability, decreased lacrimation, and absence of the corneal reflex are factors that may explain the development of these manifestations in CIPA. The early detection of these manifestations can improve patient conditions and prevent further complications, in addition to helping to guide the clinical diagnosis of CIPA in these patients. Full article

Background and Clinical Significance: Ocular cicatricial pemphigoid (OCP) is a rare autoimmune disease affecting the conjunctiva and oral mucosa. Chronic inflammation causes conjunctival scarring, leading to symblepharon, trichiasis, corneal damage, and possible blindness. Diagnosis is clinical, supported by biopsy and immunofluorescence. Treatment includes systemic corticosteroids, immunosuppressants, and biologics in refractory cases. Case Presentation: A 64-year-old male presented with ocular irritation, trichiasis, and counting fingers (CF) visual acuity in the left eye. Slit-lamp examination revealed conjunctival inflammation, corneal epithelial defect, and symblepharon in the left eye. Biopsy confirmed ocular cicatricial pemphigoid (OCP). He was treated with topical steroids, cyclosporine, subconjunctival injections, and systemic corticosteroids, followed by surgery, which improved BCVA to 0.10 logMAR. Two years later, disease progression resulted in severe inflammation and visual decline in both eyes. Systemic azathioprine and corticosteroids achieved partial control. Due to insufficient response, rituximab therapy was initiated, leading to significant reduction in inflammation and stabilization of disease. Right eye BCVA improved to 0.16 logMAR; the left remained at CF. The patient continues to receive rituximab during exacerbations and is under regular follow-up. Conclusions: Early diagnosis and timely systemic treatment are essential in preventing vision loss in OCP. In refractory cases, biologic agents like rituximab may offer effective disease control. Full article

Dry eye disease (DED) is characterized by tear film instability and oxidative stress-induced epithelial damage. This study was conducted to compare the therapeutic effects of 2% rebamipide (REB) and 3% diquafosol (DQS) on oxidative stress-related apoptotic damage of the ocular surface in DED. Human corneal epithelial cells (HCECs) were exposed to hyperosmotic stress in vitro and treated with REB or DQS. Cell viability and cleaved caspase-3 expression were evaluated using the MTT assay and Western blotting. DED was induced in vivo in C57BL/6 mice using subcutaneous scopolamine injection. Thereafter, the mice were assigned to normal control (NC), dry eye (DE), DQS-treated (DQS), or REB-treated (REB) groups. Clinical evaluations, including measurement of tear film break-up time, corneal smoothness, and the lipid layer, were performed on days 7 and 14. In addition, CD4⁺ IFN-γ⁺ T cells, inflammatory cytokines, reactive oxygen species (ROS), lipid peroxidation markers, and corneal apoptosis were analyzed on day 14. Glycocalyx integrity and goblet cell density were also evaluated. The results indicate that REB improved HCEC survival and suppressed cleaved caspase-3 expression more effectively than DQS (p < 0.05). Both treatments improved clinical outcomes in the murine dry eye model; however, REB showed superior efficacy in reducing ROS levels, lipid peroxidation, and apoptosis, and in preserving corneal glycocalyx integrity and conjunctival goblet cell density. These findings highlight the therapeutic potential and protective effects of REB against oxidative stress-related damage and apoptosis in DED. Full article

Although approached through many concepts, the pleiotropic healing issue, specifically, maintaining/reestablishing tissue integrity, remains a central challenge in pharmacology, particularly when the process is misdirected or not properly controlled. Robert and Szabo’s concept of cytoprotection holds that innate cell (epithelial (Robert), endothelial (Szabo)) integrity and protection/maintenance/reestablishment in the stomach is translated to other organ therapy (cytoprotection → organoprotection) via the cytoprotection agent’s effect. Therefore, we defend stable gastric pentadecapeptide BPC 157 therapy’s efficacy and pleiotropic beneficial effects, along with its high safety (LD1 not achieved), against speculation of its negative impact, speculation of angiogenesis toward tumorigenesis, increased NO and eNOS, damaging free radical formation, and neurodegenerative diseases (Parkinson’s disease and Alzheimer’s disease). Contrarily, in wound healing and general healing capabilities, as reviewed, as a cytoprotective agent and native cytoprotection mediator, BPC 157 controls angiogenesis and the NO-system’s healing functions and counteracts the pathological presentation of neurodegenerative diseases in acknowledged animal models (i.e., Parkinson’s disease and Alzheimer’s disease), and it presents prominent anti-tumor potential in vivo and in vitro. BPC 157 resolved cornea transparency maintenance, cornea healing “angiogenic privilege” (vs. angiogenesis/neovascularization/tumorigenesis), and it does not produce corneal neovascularization but rather opposes it. Per Folkman’s concept, it demonstrates an anti-tumor effect in vivo and in vitro. BPC 157 exhibits a distinctive effect on the NO-level (increase vs. decrease), always combined with the counteraction of free radical formation, and, in mice and rats, BPC 157 therapy counteracts Parkinson’s disease-like and Alzheimer’s disease-like disturbances. Thus, BPC 157 therapy means targeting angiogenesis and NO’s cytotoxic and damaging actions but maintaining, promoting, or recovering their essential protective functions. Full article

This study investigates the pathophysiological process of healed perforated corneal ulcers (HPCUs) in humans. All subjects underwent keratoplasty due to opacities or leakage from HPCUs. Half of each specimen was fixed with 4% glutaraldehyde for transmission electron microscope (TEM) examination. The other half was fixed in 10% formaldehyde for immunofluorescence (IF) examination. TEM identified layered structures with two cell types (polygonal and elongated) connected by gap or adherent junctions during early stage of healing. Both apoptotic and mitotic changes were found in both types of cells. There were no endothelial cells or Descemet’s membrane (DM) present in early stage of healing. During the intermediate stage, the healed area comprised three layers: epithelium, Bowman’s layer, and stroma, with an increase in stromal collagen. Later, adjacent endothelial cells crept in, forming DM and completing the cornea’s 5-layer structure. IF examinations revealed that vimentin⁺ and α-smooth muscle actin (αSMA)⁺ myofibroblasts gathered around the damaged site. Proliferating cell nuclear antigen⁺ cells, which indicated cell proliferation, were found in both cells. Anti-phospho-histone H2AX antibodies were found in some epithelial cells. CK14-positive cells were only found in superficial polygonal cells. Corneal wound healing is a complex process that includes apoptosis, cell migration, mitosis, differentiation, and extracellular matrix remodeling. Full article

Dry eye is an ophthalmic disease with an intricate pathomechanism, and there are no effective interventions or medications available. We investigated the effects of a peptide, DFCPPGFNTK (DFC), screened from tilapia skin hydrolysate on dry eye and its underlying mechanisms. In vitro, human corneal epithelial cells (HCECs) were challenged by 100 mM NaCl in a hyperosmotic environment. DFC restored the cell viability of HCECs induced by NaCl, reduced the transition of mitochondrial membrane potential, delayed the apoptosis of damaged cells, reduced the production of reactive oxygen (ROS) and malondialdehyde (MDA), increased the activities of superoxide dismutase (SOD) and catalase (CAT), and increased the expression rate of Bcl-2/Bax. Compared to the model group, the protein expression levels of COX-2 and iNOS were down-regulated, the mRNA expression of Tnf-α and Il-6 were decreased, the protein expression levels of Nrf2 and HO-1 were increased, and the levels of autophagy-related proteins p62 and LC3B were regulated. In vivo, the dry eye model was developed by administering eye drops of 0.2% BAC to mice for 14 days. DFC increased tear secretion, changed the morphology of tear fern crystals, prevented corneal epithelial thinning, reduced the loss of conjunctival goblet cells (GCs), and inhibited the apoptosis of mice corneal epithelial cells. In summary, DFC improved dry eye by inhibiting oxidative stress, apoptosis, inflammation, and autophagy. Full article