Equine recurrent uveitis

BACKGROUND: Uveitis is common in horses, potentially turning chronic (persistent or recurrent) resulting in impaired vision or blindness. All mainstay therapeutics aims at controlling inflammation, but long-term or lifelong treatment is often needed with possibly severe side effects. Therefore, intravitreal injections with low-dose gentamicin (IVGI) have been used in attempt to give a long-lasting result with potentially less side effects. OBJECTIVES: To retrospectively assess outcome and long-term complications following one or two low-dose IVGI in Swedish horses with chronic uveitis...

The perception of circulating granulocytes as cells with a predetermined immune response mainly triggered by pathogens is evolving, recognizing their functional heterogeneity and adaptability, particularly within the neutrophil subset. The involvement of these cells in the pathophysiology of autoimmune uveitis has become increasingly clear, yet their exact role remains elusive. We used an equine model for autoimmune-mediated recurrent pan-uveitis to investigate early responses of granulocytes in different inflammatory environments...

Regenerative therapy and biologics have the promise to treat equine ocular surface diseases, including corneal ulceration or immune-mediated keratitis, or intraocular diseases such as uveitis. The use of blood-derived products such as serum or platelet-rich plasma, mesenchymal stem cells, or amniotic membrane grafts may be beneficial for the treatment of ulcerative and chronic keratitis in horses. Furthermore, the use of stem cells or gene therapy has promise for the treatment of Intraocular diseases such as equine recurrent uveitis by providing efficacious, practical, and long-term therapy for these blinding diseases...

OBJECTIVE: The objective of this study was to use shotgun label-free tandem mass spectrometry (LF-MS/MS) to evaluate aqueous humor (AH) from horses with uveitis (UH) compared to ophthalmologically healthy horses (HH). ANIMALS STUDIED: Twelve horses diagnosed with uveitis based on ophthalmic examination and six ophthalmologically healthy horses (postmortem) purchased for teaching purposes. PROCEDURES: All horses received a complete ophthalmic examination and physical exam...

OBJECTIVE: The objective of the study was to determine the effect of gentamicin on CD3+ T-lymphocyte proliferation and cell viability using an in vitro cell culture model as a means of investigating the mechanism of action of low-dose intravitreal gentamicin injection. ANIMALS STUDIED: Three adult horses with no evidence of ophthalmic or systemic disease. PROCEDURE: Peripheral blood lymphocytes were treated with gentamicin at concentrations 37...

PURPOSE: To evaluate the correlation between equine pectinate ligament descemetization and ocular disease. METHODS: The pathology database of the North Carolina State University Veterinary Medical Center was searched from 2010-2021 for all equine globes. Disease status was then assigned as affected by glaucoma, uveitis, or "other" based upon clinical records. The iridocorneal angles (ICA) of each globe were evaluated for the presence of pectinate ligament descemetization, the length of descemetization, as well as for the degree of angle collapse and the extent of cellular infiltrate or proteinaceous debris...

Horses with recurrent uveitis can be treated by intravitreal injection of low dose gentamicin under sedation and after local anaesthetic techniques including the retrobulbar nerve block. Since it is reported that retinal degeneration can be secondary to an acute increase of intraocular pressure (IOP), the current randomized controlled study was carried out in order to investigate the changes in IOP following retrobulbar anaesthesia, with two different volumes of local anesthetic (lidocaine) solution (10 and 5 mL), and intravitreal injection of 6 mg gentamicin in two different volumes of solution (0...

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...

Equine recurrent uveitis (ERU) is a blinding ocular disorder among horses, and the Appaloosa horse breed is disproportionally affected by a chronic form of this intraocular inflammatory disease known as insidious uveitis. Strong breed predisposition and previous investigations suggest that there is a genetic component to the pathology of insidious uveitis among Appaloosa horses; however, no estimates of the heritability of the disease have previously been determined. This study aimed to characterize the genetic underpinning of the disease by estimating the heritability for insidious uveitis among Appaloosas...

This review, which is part of the "Currents in One Health" series, describes the importance of the study of immune-mediated ocular disease in the development of innovative therapeutics, such as cell and gene therapy for the eye. Recent examples of cell and gene therapy studies from the author's laboratory are reviewed to emphasize the importance of One Health initiatives in developing innovative therapies for ocular diseases. Spontaneous immune-mediated corneal disease is common in horses, cats, dogs, and humans...

BACKGROUND: Equine recurrent uveitis (ERU) is the leading cause of blindness for horses; previous research implicated the leopard complex spotting allele (LP) as a genetic risk factor for insidious uveitis in the Appaloosa. There is limited information about risk in the Knabstrupper. OBJECTIVE: To evaluate clinical manifestations, disease frequency, and potential risk factors for ERU in Knabstrupper horses. STUDY DESIGN: Cross-sectional study...

In the pathophysiology of autoimmune-mediated uveitis, granulocytes have emerged as possible disease mediators and were shown to be pre-activated in equine recurrent uveitis (ERU), a spontaneous disease model. We therefore used granulocytes from ERU horses to identify early molecular mechanisms involved in this dysregulated innate immune response. Primary granulocytes from healthy and ERU horses were stimulated with IL8, and cellular response was analyzed with differential proteomics, which revealed significant differences in protein abundance of 170 proteins in ERU...

In the equine clinic of the LMU in Munich, therapeutic vitrectomies have been routinely performed in horses for three decades. The vitreous samples obtained during vitrectomies were usually tested for anti- Leptospira antibodies and for more than 20 years also by PCR for leptospiral DNA. If the indication for surgery was ophthalmologically inconclusive, an aqueous humor was collected preoperatively and examined for evidence of leptospiral infection. In this study, medical records from 2002 to 2017 were analyzed...

Equine recurrent uveitis (ERU) is a spontaneous, painful, and vision threatening disease affecting up to 25% of equine populations worldwide. Current treatments of ERU are non-specific and have many side effects which limits them to short-term use. In order to develop an effective therapy for ERU, we investigated the use of adeno-associated virus (AAV) gene therapy, exploiting a natural immune tolerance mechanism induced by equine interleukin-10 (Equine-IL10). The purpose of this study was to evaluate the therapeutic efficacy of a single intravitreal (IVT) dose of AAV8-Equine-IL10 gene therapy for inhibition of experimental autoimmune uveitis (EAU) in rats...

OBJECTIVE: To determine the prevalence of ocular disease in draft horses in the United States. ANIMALS: Draft horses of various breeds and ages. PROCEDURE: Nondilated ophthalmic examination was performed using slit lamp biomicroscopy and indirect ophthalmoscopy. Intraocular pressures were measured when possible. RESULTS: One hundred sixty-five draft horses were examined. Age range: 10 days to 33 years (mean 10.8 years, median 10 years); 87 geldings (52...

Equine recurrent uveitis (ERU) is an ocular inflammatory disease that can be difficult to manage clinically. As such, it is the leading cause of bilateral blindness for horses. ERU is suspected to have a complex autoimmune etiology with both environmental and genetic risk factors contributing to onset and disease progression in some or all cases. Work in recent years has aimed at unraveling the primary triggers, such as infectious agents and inherited breed-specific risk factors, for disease onset, persistence, and progression...

BACKGROUND: Iris cysts in horses are often asymptomatic and noticed incidentally. However, cysts can cause local corneal oedema and erratic behaviour like shying, decreased performance and head-shaking. OBJECTIVES: To describe the use of diode laser as a noninvasive treatment option for iris cysts in the horse and to document factors influencing its efficacy, associated complications, long-term outcome and rate of recurrence. STUDY DESIGN: Retrospective case series...

Equine recurrent uveitis (ERU) is a painful and debilitating autoimmune disease and represents the only spontaneous model of human recurrent uveitis (RU). Despite the efficacy of existing treatments, RU remains a leading cause of visual handicap in horses and humans. Cytokines, which utilize Janus kinase 2 (Jak2) for signaling, drive the inflammatory processes in ERU that promote blindness. Notably, suppressor of cytokine signaling 1 (SOCS1), which naturally limits the activation of Jak2 through binding interactions, is often deficient in autoimmune disease patients...

Equine recurrent uveitis (ERU) is an autoimmune disease defined by inflammation of the uveal tract of the eye. The cause of ERU is thought to be complex, involving both genetic and environmental factors. The purpose of this study was to investigate potential genetic risk factors for ERU in the Icelandic horse. Fifty-six Icelandic horses (11 affected with ERU and 45 controls) living in Denmark and the USA, eight years or older, were included in the study. A case-control GWAS was performed using the GGP Equine 80K array on the Illumina Infinium HD Beadchip using 40 horses...

PURPOSE: To describe the most common ocular abnormalities in the Icelandic horse with focus on equine recurrent uveitis (ERU) and association between ocular abnormalities and summer eczema and coat colors. METHODS: A descriptive cross-sectional study. A complete physical and ophthalmic examination as well as measurement of serum titers for Leptospira serovariants was performed on Icelandic horses from Denmark (DK) and the United States (USA). RESULTS: One hundred and twelve Icelandic horses living in DK and 26 Icelandic horses living in the United States were included in this study (total of 138 horses, 274 eyes)...