Dry eye disease and uveitis: A closer look at immune mechanisms in animal models of two ocular autoimmune diseases

Clinical management of eye diseases: carotenoids and their nanoformulations as choice of therapeutics

Eye diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR), impose a substantial health cost on a worldwide scale. Carotenoids have emerged as intriguing candidates for pharmacological treatment of various disorders. Their therapeutic effectiveness, however, is hindered by poor solubility and vulnerability to degradation. Nanocarriers, such as nanoparticles, liposomes, and micelles, provide a transformational way to overcome these limits. This review explores the pharmacological potential of carotenoids, namely lutein, zeaxanthin, and astaxanthin, to treat several ocular disorders. The main emphasis is on their anti-inflammatory and antioxidant actions, which help to counteract inflammation and oxidative stress, crucial factors in the development of AMD and DR. The review evaluates the significant benefits of nano-formulated carotenoids, such as improved bioavailability, higher cellular absorption, precise administration to particular ocular tissues, and greater biostability, which make them superior to conventional carotenoids. Some clinical studies on the beneficial properties of carotenoids in eye diseases are discussed. Furthermore, safety and regulatory concerns are also taken into account. Ultimately, carotenoids, especially when created in their nano form, have significant potential for safeguarding eyesight and enhancing the overall well-being of several individuals afflicted with vision-endangering eye diseases.

ROS-responsive celastrol-nanomedicine alleviates inflammation for dry eye disease

Dry eye disease (DED) is a major global eye disease leading to severe eye discomfort and even vision impairment. The incidence of DED has been gradually increasing with the high frequency of use of electronic devices. It has been demonstrated that celastrol (Cel) has excellent therapeutic efficacy in ocular disorders. However, the poor water solubility and short half-life of Cel limit its further therapeutic applications. In this work, a reactive oxygen species (ROS) sensitive polymeric micelle was fabricated for Cel delivery. The micelles improve the solubility of Cel, and the resulting Cel loaded micelles exhibit an enhanced intervention effect for DED. Thein vitroresults demonstrated that Cel-nanomedicine had a marked ROS responsive release behavior. The results ofin vitroandin vivoexperiments demonstrated that Cel has excellent biological activities to alleviate inflammation in DED by inhibiting TLR4 signaling activation and reducing pro-inflammatory cytokine expression. Therefore, the Cel nanomedicine can effectively eliminate ocular inflammation, promote corneal epithelial repair, and restore the number of goblet cells and tear secretion, providing a new option for the treatment of DED.

Effect of serum metabolites on the risk of iridocyclitis: a bidirectional Mendelian randomization study

Previous research has linked serum metabolite levels to iridocyclitis, yet their causal relationship remains unexplored. This study investigated this potential causality by analyzing pooled data from 7824 iridocyclitis patients in a Genome-Wide Association Study (GWAS) using Mendelian randomization (MR) and linkage disequilibrium score regression (LDSC). Employing rigorous quality control and comprehensive statistical methods, including sensitivity analyses, we examined the influence of 486 serum metabolites on iridocyclitis. Our MR analysis identified 23 metabolites with significant causal effects on iridocyclitis, comprising 17 known and 6 unidentified metabolites. Further refinement using Cochran's Q test and MR-PRESSO indicated 16 metabolites significantly associated with iridocyclitis risk. LDSC highlighted the heritability of certain metabolites, underscoring genetic influences on their levels. Notably, tryptophan, proline, theobromine, and 7-methylxanthine emerged as risk factors, while 3,4-dihydroxybutyrate appeared protective. These findings enhance our understanding of the metabolic interactions in iridocyclitis, offering insights for diagnosis, unraveling pathophysiological mechanisms, and informing potential avenues for prevention and personalized treatment.

Beneficial mechanisms of dimethyl fumarate in autoimmune uveitis: insights from single-cell RNA sequencing

BACKGROUND

Dimethyl fumarate (DMF) is a fumaric acid ester that exhibits immunoregulatory and anti-inflammatory properties. However, the function of DMF in autoimmune uveitis (AU) is incompletely understood, and studies comprehensively exploring the impact of DMF on immune cells are still lacking.

METHODS

To explore the function of DMF in uveitis and its underlying mechanisms, we conducted single-cell RNA sequencing (scRNA-seq) on the cervical draining lymph node (CDLN) cells of normal, experimental autoimmune uveitis (EAU), and DMF-treated EAU mice. Additionally, we integrated scRNA-seq data of the retina and CDLNs to identify the potential impact of DMF on ocular immune cell infiltration. Flow cytometry was conducted to verify the potential target molecules of DMF.

RESULTS

Our study showed that DMF treatment effectively ameliorated EAU symptoms. The proportional and transcriptional alterations in each immune cell type during EAU were reversed by DMF treatment. Bioinformatics analysis in our study indicated that the enhanced expression of Pim1 and Cxcr4 in EAU was reversed by DMF treatment. Further experiments demonstrated that DMF restored the balance between effector T (Teff) /regulatory T (Treg) cells through inhibiting the pathway of PIM1-protein kinase B (AKT)-Forkhead box O1 (FOXO1). By incorporating the scRNA-seq data of the retina from EAU mice into analysis, our study identified that T cells highly expressing Pim1 and Cxcr4 were enriched in the retina. DMF repressed the ocular infiltration of Teff cells, and this effect might depend on its inhibition of PIM1 and CXCR4 expression. Additionally, our study indicated that DMF might reduce the proportion of plasma cells by inhibiting PIM1 expression in B cells.

CONCLUSIONS

DMF effectively attenuated EAU symptoms. During EAU, DMF reversed the Teff/Treg cell imbalance and suppressed the ocular infiltration of Teff cells by inhibiting PIM1 and CXCR4 expression. Thus, DMF may act as a new drug option for the treatment of AU.

Autoimmune Disease-Related Dry Eye Diseases and Their Placement Under the Revised Classification Systems: An Update

Dry eye disease (DED) is a chronic and progressive disorder involving the ocular surface, characterized by disturbances in tear film composition, instability of the tear film, and inflammation of the ocular surface. There are two forms of DED: aqueous-deficient dry eye (ADDE) and evaporative dry eye (EDE). Autoimmune diseases are systemic disorders involving multiple organs, including the eyes, and have a significant impact on DED. There have been multiple studies demonstrating the relation between autoimmune diseases and DED. This article reviews the current knowledge regarding the epidemiological characteristics, pathogenesis, and treatments of autoimmune disease-related DED.

Pathogenesis and current therapies for non-infectious uveitis

Non-infectious uveitis (NIU) is a disorder with various etiologies and is characterized by eye inflammation, mainly affecting people of working age. An accurate diagnosis of NIU is crucial for appropriate therapy. The aim of therapy is to improve vision, relieve ocular inflammation, prevent relapse, and avoid treatment side effects. At present, corticosteroids are the mainstay of topical or systemic therapy. However, repeated injections are required for the treatment of chronic NIU. Recently, new drug delivery systems that may ensure intraocular delivery of therapeutic drug levels have been highlighted. Furthermore, with the development of immunosuppressants and biologics, specific therapies can be selected based on the needs of each patient. Immunosuppressants used in the treatment of NIU include calcineurin inhibitors and antimetabolites. However, systemic immunosuppressive therapy itself is associated with adverse effects due to the inhibition of immune function. In patients with refractory NIU or those who cannot tolerate corticosteroids and immunosuppressors, biologics have emerged as alternative treatments. Thus, to improve the prognosis of patients with NIU, NIU should be managed with different drugs according to the response to treatment and possible side effects.

JAK inhibitors and autoimmune rheumatic diseases

The four Janus kinase (JAK) proteins and the seven Signal Transducers of Activated Transcription (STAT) mediate intracellular signal transduction downstream of cytokine receptors, which are involved in the pathology of allergic, autoimmune, and inflammatory diseases. The development of targeted small-molecule treatments with diverse selective inhibitory profiles, such as JAK inhibitors (JAKi), has supported an important change in the treatment of multiple disorders. Indeed, JAKi inhibit intracellular signalling controlled by numerous cytokines implicated in the disease process of rheumatoid arthritis and several other inflammatory and immune diseases. Therefore, JAKi have the capacity to target multiple pathways of those diseases. Other autoimmune diseases treated with JAKi include systemic sclerosis, systemic lupus erythematosus, dermatomyositis, primary Sjogren's syndrome, and vasculitis. In all of these cases, innate immunity stimulation activates adaptive immunity, resulting in the production of autoreactive T cells as well as the stimulation and differentiation of B cells. Mechanism-based treatments that target JAK-STAT pathways have the possibility of improving outcomes by reducing the consumption of glucocorticoids and/or non-specific immunosuppressive drugs in the management of systemic immune-mediated inflammatory diseases.

Clinical relationship between dry eye disease and uveitis: a scoping review

This scoping review examined the relationship between Dry Eye Disease (DED) and Uveitis. We searched Pubmed, Embase, and LILACS databases for articles in which at least one patient had DED and uveitis concomitantly. The search produced 2381 records, and 24 studies were included in the qualitative synthesis. We concluded that DED and uveitis of any etiology could appear concomitantly in patients of any age. However, both diseases seem to coexist more frequently in middle-aged women and cases of anterior uveitis. Therefore, it is crucial that ophthalmologists actively look for the coexistence of ocular surface abnormalities, especially in patients with these characteristics. Future studies should establish and quantify the risk factors and pathophysiological mechanisms of this coexistence to achieve an early diagnosis of both etiologies and comprehensive management of these patients.

Fallopia Japonica and Prunella vulgaris inhibit myopia progression by suppressing AKT and NFκB mediated inflammatory reactions

Background

The increased global incidence of myopia requires the establishment of therapeutic approaches. This study aimed to investigate the effect of Fallopia Japonica (FJ) and Prunella vulgaris (PV) extract on myopia caused by monocular form deprivation (MFD).

Methods

We used human retinal pigment epithelial cell to study the molecular mechanisms on how FJ extract (FJE) and PV extract (PVE) lowering the inflammation of the eye. The effect of FJE and PVE in MFD induced hamster model and explore the role of inflammation cytokines in myopia.

Results

FJE + PVE reduced IL-6, IL-8, and TNF-α expression in RPE cells. Furthermore, FJE and PVE inhibited inflammation by attenuating the phosphorylation of protein kinase B (AKT), and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) pathway. In addition, we report two resveratrol + ursolic acid compounds from FJ and PV and their inhibitory activities against IL-6, IL-8, and TNF-α expression levels in RPE cells treated with IL-6 and TNF-α. FJE, PVE, and FJE + PVE were applied to MFD hamsters and their axial length was measured after 21 days. The axial length showed statistically significant differences between phosphate-buffered saline- and FJE-, PVE-, and FJE + PVE-treated MFD eyes. FJE + PVE suppressed expressions of IL-6, IL-8, and TNF-α. They also inhibited myopia-related transforming growth factor-beta (TGF)-β1, matrix metalloproteinase (MMP)-2, and NF-κB expression while increasing type I collagen expression.

Conclusions

Overall, these results suggest that FJE + PVE may have a therapeutic effect on myopia and be used as a potential treatment option.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03747-2.

JAK-STAT Signaling Pathway in Non-Infectious Uveitis

Non-infectious uveitis (NIU) refers to various intraocular inflammatory disorders responsible for severe visual loss. Cytokines participate in the regulation of ocular homeostasis and NIU pathological processes. Cytokine receptors transmit signals by activating Janus kinase (JAK) and signal transducer and activator of transcription (STAT) proteins. Increasing evidence from human NIU and experimental models reveals the involvement of the JAK-STAT signaling pathway in NIU pathogenesis. Several small-molecule drugs that potentially inhibit multiple cytokine-dependent pathways are under investigation for treating autoimmune diseases, implicating possible applications for NIU treatment. This review summarizes the current understanding of the diverse roles of the JAK-STAT signaling pathway in ocular homeostasis and NIU pathology, providing a rationale for targeting JAKs and STATs for NIU treatment. Moreover, available evidence for the safety and efficacy of JAK inhibitors for refractory uveitis and potential approaches for treatment optimization are discussed.

Fucoxanthin: A Promising Phytochemical on Diverse Pharmacological Targets

Fucoxanthin (FX) is a special carotenoid having an allenic bond in its structure. FX is extracted from a variety of algae and edible seaweeds. It has been proved to contain numerous health benefits and preventive effects against diseases like diabetes, obesity, liver cirrhosis, malignant cancer, etc. Thus, FX can be used as a potent source of both pharmacological and nutritional ingredient to prevent infectious diseases. In this review, we gathered the information regarding the current findings on antimicrobial, antioxidant, anti-inflammatory, skin protective, anti-obesity, antidiabetic, hepatoprotective, and other properties of FX including its bioavailability and stability characteristics. This review aims to assist further biochemical studies in order to develop further pharmaceutical assets and nutritional products in combination with FX and its various metabolites.

Apolipoprotein A1 Modulates Teff/Treg Balance Through Scavenger Receptor Class B Type I-Dependent Mechanisms in Experimental Autoimmune Uveitis

Purpose

Experimental autoimmune uveitis (EAU) is a representative animal model of human uveitis. In this study, we investigated whether apolipoprotein A1 (APOA1) can alleviate EAU and explored its underlying mechanism.

Methods

Mice were immunized with interphotoreceptor retinoid-binding protein 1-20 and treated with APOA1 or vehicle. The retinas, draining lymph nodes (DLNs), and spleens were analyzed. Isolated T cells were used for proliferation, differentiation, and function assays in vitro. Selective inhibitors and pathway agonists were used to study signaling pathways. The effect of APOA1 on peripheral blood mononuclear cells (PBMCs) from uveitis patients was also examined.

Results

Administration of APOA1 ameliorated EAU. APOA1 suppressed pathogenic CD4+ T cell expansion in DLNs and spleen, and decreased the infiltration of effector T (Teff) cells into retina. APOA1 also inhibited T cell proliferation and T helper 1 cell differentiation in vitro and promoted regulatory T (Treg) cell differentiation. APOA1 restricted inflammatory cytokine production from lipopolysaccharide-stimulated PBMCs. Mechanistic studies revealed that the effect of APOA1 was mediated by scavenger receptor class B type I (SR-BI) and downstream signals including phosphatidylinositol 3-kinase/Protein kinase B (PKB, or Akt), p38 mitogen-activated protein kinase, and nuclear factor–κB.

Conclusions

APOA1 ameliorates EAU by regulating the Teff/Treg partially through SR-BI. Our results suggest that APOA1 can be a therapeutic alternative for autoimmune uveitis.

Therapeutic Potential of Microvesicles in Cell Therapy and Regenerative Medicine of Ocular Diseases With an Especial Focus on Mesenchymal Stem Cells-Derived Microvesicles

These days, mesenchymal stem cells (MSCs), because of immunomodulatory and pro-angiogenic abilities, are known as inevitable factors in regenerative medicine and cell therapy in different diseases such as ocular disorder. Moreover, researchers have indicated that exosome possess an essential potential in the therapeutic application of ocular disease. MSC-derived exosome (MSC-DE) have been identified as efficient as MSCs for treatment of eye injuries due to their small size and rapid diffusion all over the eye. MSC-DEs easily transfer their ingredients such as miRNAs, proteins, and cytokines to the inner layer in the eye and increase the reconstruction of the injured area. Furthermore, MSC-DEs deliver their immunomodulatory cargos in inflamed sites and inhibit immune cell migration, resulting in improvement of autoimmune uveitis. Interestingly, therapeutic effects were shown only in animal models that received MSC-DE. In this review, we summarized the therapeutic potential of MSCs and MSC-DE in cell therapy and regenerative medicine of ocular diseases.

Therapeutic Effect of IL-38 on Experimental Autoimmune Uveitis: Reprogrammed Immune Cell Landscape and Reduced Th17 Cell Pathogenicity

Purpose

The purpose of this study was to elucidate the effects of interleukin (IL)-38 on experimental autoimmune uveitis (EAU) and its underlying mechanisms.

Methods

Mice with EAU were treated with IL-38, and the retinas and cervical draining lymph nodes (CDLNs) were analyzed by flow cytometry. Single-cell RNA sequencing (scRNA-seq) was conducted to analyze the immune cell profiles of CDLNs from normal, EAU, and IL-38-treated mice.

Results

Administration of IL-38 attenuated EAU symptoms and reduced the proportion of T helper 17 (Th17) and T helper 1 (Th1) cells in the retinas and CDLNs. In scRNA-seq analysis, IL-38 downregulated the IL-17 signaling pathway and reduced the expression of Th17 cell pathogenicity-related genes (Csf2 and Il23r), findings which were also confirmed by flow cytometry. In vitro, IL-38 reduced the granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation function of IL-23 and inhibited IL-23R expression in Th17 cells. Moreover, when co-cultured with Th17 cells, IL-38 prevented IL-23 production in antigen-presenting cells (APCs).

Conclusions

Our data demonstrate the therapeutic effect of IL-38 on EAU, and suggest that the effect of IL-38 may be caused by dampening of the GM-CSF/IL-23R/IL-23 feedback loop between Th17 cells and APCs.

Uveal Effusion Syndrome as the Initial Manifestation of Primary Sjögren's Syndrome and Review of the Literature

Purpose: The authors report a38-year-old woman with primary Sjögren's syndrome who initially showed recurrent blurred vision caused by uveal effusion syndrome and later developed dry mouth, dry eyes, and arthralgia. During the 5-year-course of disease, the patient's 3-time-onset was all manifested as blurred vision after decreased immunity. Despite the initial absence of sufficient immunological evidence, the final presence of positive serum anti-SS-A, rheumatoid factors, ANA, and inflammatory findings in minor salivary gland biopsy indicated primary Sjögren's syndrome.Methods: Retrospective review of a case note.Conclusions: The manifestation of UES requires further exploration of its real pathogenesis, and the possibility of systemic disease should never be excluded.

CD47 Deficiency Ameliorates Ocular Autoimmune Inflammation

Autoimmune uveitis is a sight-threatening ocular inflammatory condition in which the retina and uveal tissues become a target of autoreactive immune cells. The CD47 is a ubiquitously expressed transmembrane protein which plays multiple roles in fundamental cellular functions including phagocytosis, proliferation, and adhesion. Signal regulatory protein alpha (SIRPα), one of the CD47 ligands, is predominantly expressed in myeloid lineage cells such as dendritic cells (DCs) or macrophages, and CD47-SIRPα signaling pathway is implicated in the development of autoimmune diseases. Our current study demonstrates how CD47 depletion is effective in the prevention of experimental autoimmune uveitis (EAU), an animal model of human autoimmune uveitis, in animals deficient of CD47 (CD47-/- ). Systemic suppression of SIRPα+ DCs in animals deficient in CD47 resulted in the inability of autoreactive CD4+ T cells to develop, which is crucial to induction of EAU. Of interest, retinal microglia, the resident immune cell of the retina, express SIRPα, however these cells were not operative in EAU suppression in response to CD47 depletion. These results identify CD47 as a significant regulator in the development of SIRPα+ DCs that is vital to disease induction in EAU.

A Review of the Various Roles and Participation Levels of B-Cells in Non-Infectious Uveitis

Non-infectious uveitis is an inflammatory disorder of the eye that accounts for severe visual loss without evident infectious agents. While T cells are supposed to dominate the induction of inflammation in non-infectious uveitis, the role of B cells in the pathogenesis of this disease is obscure. Therefore, this review aimed to discuss diverse B-cell participation in different non-infectious uveitides and their roles in the pathogenesis of this disease as well as the mechanism of action of rituximab. Increasing evidence from experimental models and human non-infectious uveitis has suggested the participation of B cells in non-infectious uveitis. The participation levels vary in different uveitides. Furthermore, B cells play multiple roles in the pathogenic mechanisms. B cells produce autoantibodies, regulate T cell responses via antibody-independent functions, and constitute ectopic lymphoid structures. Regulatory B cells perform pivotal anti-inflammatory functions in non-infectious uveitis. Rituximab may work by depleting pro-inflammatory B cells and restoring the quantity and function of regulatory B cells in this disease. Identifying the levels of B-cell participation and the associated roles is beneficial for optimizing therapy. Diversified experimental model choices and emerging tools and/or methods are conducive for future studies on this topic.

Associations between seven-year C-reactive protein trajectory or pack-years smoked with choroidal or retinal thicknesses in young adults

Inflammation and cigarette smoking predispose to macular diseases, and choroidal and retinal thinning. We explored the choroidal and retinal thicknesses in young adults against their 7-year C-reactive protein (CRP) level trajectory and pack-years smoked. Participants from the Raine study, a longitudinal cohort study, had serum CRP levels analysed at the 14-, 17-, and 20-year follow-ups. Group-based trajectory modelling was used to classify participants according to their 7-year CRP levels. At the 20-year follow-up (at 18–22 years old), participants completed questionnaires on their smoking history, and underwent optical coherence tomography imaging to obtain their choroidal and retinal thicknesses at the macula. Three CRP trajectories were identified: consistently low CRP levels (78% of sample), increasing (11%), or consistently high (11%). 340 and 1035 participants were included in the choroidal and retinal thickness analyses, respectively. Compared to those in the “Low” trajectory group, participants in the “Increasing” and “High” groups had 14–21 μm thinner choroids at most macular regions. Every additional pack-year smoked was linked with a 0.06–0.10 μm thinner retina at the inner and outer macular rings, suggesting a dose-dependent relationship between smoking and thinner retinas. These associations may suggest that an increased risk of future visual impairment or eye disease associated with these risk factors may be present since young adulthood.

Biotherapies in Uveitis

Non-infectious uveitis (NIU) represents one of the leading causes of blindness in developed countries. The therapeutic strategy aims to rapidly control intra-ocular inflammation, prevent irremediable ocular damage, allow corticosteroid sparing and save the vision, and has evolved over the last few years. Anterior NIU is mostly managed with topical treatment in adults. However, for intermediate, posterior and pan-uveitis, notably when both eyes are involved, systemic treatment is usually warranted. Biotherapies are recommended in case of inefficacy or non-tolerance of conventional immunosuppressive drugs in non-anterior NIU. Anti-tumor necrosis factor alpha (anti-TNF-α) agents are by far the most widely used, especially adalimumab (ADA) and infliximab (IFX). In case of sight-threatening uveitis in Behçet's disease or in case of risk of severe recurrences, respectively IFX and ADA may be recommended as first-line therapy. Many questions are left unanswered; how long to treat NIU, how to discontinue anti-TNF-α agents, what biologic to use in case of anti-TNF-α failure? The objective of this review is to present an updated overview of knowledge on the use of biological treatments in NIU.

In Vivo Anti-Inflammation Potential of Aster koraiensis Extract for Dry Eye Syndrome by the Protection of Ocular Surface

Dry eye syndrome (DES) is a corneal disease often characterized by an irritating, itching feeling in the eyes and light sensitivity. Inflammation and endoplasmic reticulum (ER) stress may play a crucial role in the pathogenesis of DES, although the underlying mechanism remains elusive. Aster koraiensis has been used traditionally as an edible herb in Korea. It has been reported to have wound-healing and inhibitory effects against insulin resistance and inflammation. Here, we examined the inhibitory effects of inflammation and ER stress by A. koraiensis extract (AKE) in animal model and human retinal pigmented epithelial (ARPE-19) cells. Oral administration of AKE mitigated DE symptoms, including reduced corneal epithelial thickness, increased the gap between lacrimal gland tissues in experimental animals and decreased tear production. It also inhibited inflammatory responses in the corneal epithelium and lacrimal gland. Consequently, the activation of NF-κB was attenuated by the suppression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Moreover, AKE treatment ameliorated TNF-α-inducible ocular inflammation and thapsigargin (Tg)-inducible ER stress in animal model and human retinal pigmented epithelial (ARPE-19) cells. These results prove that AKE prevents detrimental functional and histological remodeling on the ocular surface and in the lacrimal gland through inhibition of inflammation and ER stress, suggesting its potential as functional food material for improvement of DES.

Cluster Analysis of Dry Eye Disease Models Based on Immune Cell Parameters - New Insight Into Therapeutic Perspective

Dry eye disease (DED) can be represented as a display of disease in the mucosal part of the eye. It is quite distinct from the retinal side of the eye which connects with the neurons and thus represents the neuroimmunological disease. DED can occur either by the internal damage of the T cells inside the body or by microbial infections. Here we summarize the most common animal model systems used for DED relating to immune factors. We aimed to identify the most important immune cell/cytokine among the animal models of the disease. We also show the essential immune factors which are being tested for DED treatment. In our results, both the mechanism and the treatment of its animal models indicate the involvement of Th1 cells and the pro-inflammatory cytokine (IL-1β and TNF-α) related to the Th1-cells. The study is intended to increase the knowledge of the animal models in the field of the ocular surface along with the opening of a dimension of thoughts while designing a new animal model or treatment paradigm for ocular surface inflammatory disorders.

Preparation and characterization of a pterostilbene-peptide prodrug nanomedicine for the management of dry eye

In the present study, a pterostilbene-peptide amphiphile (PS-GA-RGD) that can spontaneously self-assemble into prodrug nanomedicine, was rationally designed and developed as a novel ophthalmic formulation for the potential management of dry eye. The formed PS-GA-RGD nanomedicine was characterized by dynamic latter scattering (DLS) and transmission electron microscopy (TEM). After esterase treatment, active pterostilbene (PS) sustainably released from the PS-GA-RGD nanomedicine within 48 h, as indicated by an in vitro release study. In comparison with native PS, the formed PS-GA-RGD nanomedicine caused minimal cytotoxicity towards RAW 264.7 and HCEC cells in the 0-20 μM range and did not delay wound healing of HCEC monolayer within 6 h. Furthermore, PS-GA-RGD nanomedicine effectively reduced the intracellular reactive oxygen species (ROS) level in H₂O₂ challenged RAW264.7 macrophages and remarkably suppressed the secretion of inflammatory cytokines (e.g., NO, TNF-α, and IL-6) in lipopolysaccharide (LPS) activated RAW264.7 macrophages. Ocular tolerance to the proposed PS-GA-RGD nanomedicine was good after a single instillation in in vivo ocular irritation tests. Overall, the proposed PS-GA-RGD nanomedicine had potent anti-oxidant capacity and anti-inflammatory efficacy, which may be a promising ophthalmic formulation for the management of dry eye.

Dry Eye in Systemic Sclerosis Patients: Novel Methods to Monitor Disease Activity

Background: In systemic sclerosis (SSc) patients, dry eye syndrome (DES) is the most frequent ocular feature. The aim of this study was to investigate ocular DES-related SSc patients and to establish any correlation with the severity of the disease. Methods: Retrospectively, data from 60 patients with SSc underwent ophthalmic examination, where non-invasive film tear break-up time (NIF-TBUT), tear film lipid layer thickness (LLT), anesthetic-free Schirmer test I, tear osmolarity measurement (TearLab System), and modified Rodnan skin score (mRSS) data were collected. The visual analog scale (VAS) and Symptom Assessment in Dry Eye (SANDE) methods were utilized. The results were correlated with mRSS and the duration of SSc. Results: Severe DES occurred in 84% of cases, and was more severe in women. The eyelids were involved in 86.6%, secondary to meibomian gland disease (MGD). A direct correlation was found between the tear osmolarity (mean 328.51 ± 23.8 SD) and skin score (mRSS) (r = 0.79; p < 0.01). Significantly reduced NIF-TBUT, LLT, and Schirmer test I values were observed in the case of severe skin involvement. Conclusions: SSc patients show lipid tear dysfunction related to the severity and duration of the disease due to inflammation and the subsequent atrophy of the meibomian glands.

The off-label uses profile of tofacitinib in systemic rheumatic diseases

Tofacitinib is an oral, small molecule JAK inhibitor that targets JAK1/JAK3. Tofacitinib has been approved by the FDA to be used in the treatments of rheumatoid arthritis, psoriatic arthritis, plaque psoriasis and ulcerative colitis. Considering the important pathogenic role of the JAK/STAT pathway in autoimmune disease, tofacitinib could be, theoretically, effective in the treatments of other systemic rheumatic diseases. Here we reviewed the published literature to profile the perspectives about the off-label uses of tofacitinib, especially in those refractory cases with poor response to conventional therapies or biologic agents. Tofacitinib can be a new therapeutic option and help reducing hormone dependence and correlated adverse events.

Can the CRP/albumin Ratio be Used as a New Indicator of Activation in Patients with Uveitis?

Purpose: To evaluate whether the C-reactive protein (CRP)/albumin ratio (CAR) in patients with uveitis during an attack is a marker that can give information about the activity, severity and prognosis of the disease.Methods: This study included 35 patients with an uveitis attack and 35 healthy volunteers. The localization and severity of uveitis were recorded. Patients' complete blood count (CBC) during the attack, CRP, CAR, erythrocyte sedimentation rate(ESR), neutrophil/lymphocyte ratio(NLR), and platelet/lymphocyte ratio(PLR) were recorded.Results: The mean age was 34.1 ± 12.5 years for the 35 uveitis cases and 30.1 ± 4.1 years for the healthy volunteers. CRP and CAR were significantly higher in uveitis patients (p = .015 and 0.011, respectively). While CRP and CAR were significantly higher in severe anterior uveitis than mild anterior uveitis (p = .036 and 0.022, respectively), only CAR was significantly higher in severe posterior and panuveitis than mild ones(p = .017).Conclusion: CAR may be an important parameter in determining the activation of the uveitis.

Phenylboronic acid-tethered chondroitin sulfate-based mucoadhesive nanostructured lipid carriers for the treatment of dry eye syndrome

Dry eye syndrome is a common eye disease that affects many people worldwide. It is usually treated with eye drops, which has low bioavailability owing to rapid clearance from the ocular surface and leads to poor patient compliance and side effects. For the purpose of improving the therapeutic efficacy, nanostructured lipid carrier (NLC)-loaded dexamethasone (DEX) was prepared and functionalized with (3-aminomethylphenyl)boronic acid-conjugated chondroitin sulfate (APBA-ChS). As APBA has a boronic acid group, it can form a high-affinity complex with sialic acids present in the ocular mucin, which contributes to extension of corneal retention time and improvement of drug delivery. Compared with eye drops, Rhodamine B (RhB)-labeled APBA-ChS-NLC could significantly prolong the residence time on the corneal surface. Moreover, the DEX-APBA-ChS-NLC showed no irritation to the rabbit eye as indicated in irritation studies and histological images. The pharmacodynamics study indicated that DEX-APBA-ChS-NLC could relieve symptoms of dry eye disease in rabbits. These results demonstrated that the developed mucoadhesive drug carrier could improve the delivery of drugs and have promising potential to treat anterior eye diseases. STATEMENT OF SIGNIFICANCE: In this research, (3-aminomethylphenyl)boronic acid-conjugated chondroitin sulfate (APBA-ChS)-based nanostructured lipid carriers (NLCs) including dexamethasone (DEX) were designed and constructed. APBA-ChS, which is present on the surface of DEX-NLC and contains the boronic acid group, can form complex with sialic acids in the ocular mucin, hence leading to prolonged precorneal retention. This affinity between boronic acid and sialic acids was used to develop a mucoadhesive drug delivery system. The developed mucoadhesive drug carrier demonstrated prolonged retention time and alleviation of dry eye syndrome. APBA-ChS-based NLC may be considered a promising ocular drug delivery system for treating anterior eye diseases.

Resolution of uveitis

Autoimmune uveitis is a sight-threatening, rare disease, potentially leading to blindness. Uveitis is a synonym for intraocular inflammation, presenting as various clinical phenotypes with different underlying immune responses in patients, whereas different animal models usually represent one certain clinical and immunological type of uveitis due to genetic uniformity and the method of disease induction. T cells recognizing intraocular antigens initiate the disease, recruiting inflammatory cells (granulocytes, monocytes/macrophages) to the eyes, which cause the damage of the tissue. The treatment of uveitis so far aims at downregulation of inflammation to protect the ocular tissues from damage, and at immunosuppression to stop fueling T cell reactivity. Uveitis is usually prevented by specific mechanisms of the ocular immune privilege and the blood-eye-barriers, but once the disease is induced, mechanisms of the immune privilege as well as a variety of novel regulatory features including new Treg cell populations and suppressive cytokines are induced to downregulate the ocular inflammation and T cell responses and to avoid relapses and chronicity. Here we describe mechanisms of regulation observed in experimental animal models as well as detected in studies with peripheral lymphocytes from patients.

JAK inhibitors for the treatment of autoimmune and inflammatory diseases

Cytokines play a central role in the pathophysiology of autoimmune and inflammatory diseases. Several cytokines signal through the JAK-STAT pathway, which is now recognized as a major target to inhibit the effect of a wide array of cytokines. JAK inhibitors are increasingly used in the setting of inflammatory and autoimmune diseases. While the currently approved drugs are panJAK inhibitors, more selective small molecules are being developed and tested in various rheumatic disorders. In this extensive review, we present evidence- or hypothesis-based perspectives for these drugs in various rheumatologic conditions, such as rheumatoid arthritis, systemic lupus erythematosus, giant cell arteritis, and autoinflammatory diseases.

Recent advances of exosomes in immune-mediated eye diseases

Exosomes, nanosized extracellular vesicles of 30-150 nm, are shed by almost all cell types. Bearing proteins, lipids, RNAs, and DNAs, exosomes have emerged as vital biological mediators in cell-to-cell communication, affecting a plethora of physiological and pathological processes. Particularly, mounting evidence indicates that immunologically active exosomes can regulate both innate and adaptive immune responses. Herein, we review recent advances in the research of exosomes in several immune-mediated eye diseases, including Sjögren's syndrome (SS) dry eye, corneal allograft rejection, autoimmune uveitis, and age-related macular degeneration (AMD). Additionally, we discuss the potential of exosomes as novel biomarkers and drug delivery vesicles for the diagnosis and treatment of eye diseases.

Conjunctival HLA-DR Expression and Its Association With Symptoms and Signs in the DREAM Study

Purpose

Evaluation of dry eye disease (DED) relies on subjective symptoms and signs. We examined HLA-DR expression (HLA-DR%) in conjunctival cells, a minimally invasive biomarker with objective metrics, as an alternative method.

Methods

Dry Eye Assessment and Management (DREAM) study participants completed the Ocular Surface Disease Index questionnaire. Clinicians evaluated tear volume, tear breakup time, and corneal and conjunctival staining. Conjunctival impression cytology samples (n = 1049) were assessed for HLA-DR% in total cells (TCs), epithelial cells (ECs), and white blood cells (WBCs). Associations (categorized into <5%, 5%–15%, >15%–25%, and >25%) with symptoms and signs were evaluated.

Results

The HLA-DR% varied markedly across samples. Over 40% had <5 HLA-DR% positive cells in TCs and ECs and under 23% in WBCs. Higher HLA-DR% was associated with higher conjunctival staining for ECs (mean score 2.77 for <5% and 3.28 for >25%, linear trend P = 0.009) and TCs (mean score 2.82 for <5% and 3.29 for >25%, linear trend P = 0.04) and in TCs was associated with higher corneal staining (mean score 3.59 for <5% and 4.46 for >25%, linear trend P = 0.03). HLA-DR% in WBCs did not correlated with signs (all P ≥ 0.58), and in TCs, ECs or WBCs were not associated with symptoms (P> 0.06).

Conclusions

The distribution of HLA-DR% in conjunctival cells reflects the heterogeneity of disease in DREAM participants. High percentages of samples with <5% positive cells indicate that HLA-DR% may not be a sensitive marker for DED in all patients.

Translational Relevance

High HLA-DR% in ECs in association with high conjunctival staining may identify a subgroup of DED patients prone to epithelial disease and possibly need a different approach from current standards of treatment.

Uveitis: Autoimmunity… and beyond

OBJECTIVE

Uveitis is the most common ophthalmological finding in the practice of rheumatology and clinical immunology. The condition is frequently idiopathic but about 60 causes of uveitis have been described. Our aim was to analyze the clinical patterns and etiologies of uveitis in a tertiary referral center.

METHODS

The records of 912 consecutive patients referred to the department of internal medicine (Lyon University Hospital, Lyon, France) for the diagnostic work-up of uveitis were examined. Demographic, clinical, anatomical, and etiological features of uveitis were analyzed.

RESULTS

The mean age at onset was 48.8 years; 59.8% of the patients were women and 78.2% were Caucasians. Anterior uveitis was the most common type of uveitis (40.6%), followed by panuveitis (31.7%), posterior (18.75%) and intermediate uveitis (9%). 46.9% of the patients had idiopathic uveitis. The most common etiologies were systemic diseases (37.3%), such as sarcoidosis (17.1%), HLA-B27-related uveitis and/or spondyloarthritis (12.5%), and tuberculosis (7.5%).

CONCLUSION

We describe one of the largest cohorts of consecutive uveitis patients referred to a department of internal medicine. The high percentage of uveitis associated with underlying (systemic) diseases highlights the need for a multidisciplinary approach, in order to reduce the diagnostic delay.

Effect of Uveitis on the Development of Keratopathy: A Population-Based Cohort Study

Purpose

The purpose of this study was to evaluate the effect of uveitis on the development of various keratopathies via the use of the National Health Insurance Research Database (NHIRD) in Taiwan.

Methods

Approximately 1 million patients were randomly sampled from the registry of the NHIRD. Patients diagnosed with uveitis by ophthalmologists were enrolled in the study group after exclusion. Each individual in the study group was age and sex matched to four non-uveitis individuals who serve as the control group. In addition to keratopathy, other possible risk factors and medications were included in the multivariate model, and the effects of different subtypes of uveitis for developing keratopathies were also analyzed.

Results

A total of 4773 uveitis patients (2662 male and 2111 female) and 19,092 non-uveitis patients (10,648 male and 8444 female) were enrolled. There were 406 events of keratopathy in the study group, and another 764 events occurred in the control group. A higher incidence rate was found in the study group after adjustment (adjusted hazard ratio [aHR]: 1.772), with a greater cumulative probability (P < 0.0001). For the subgroup analysis, anterior uveitis (aHR = 1.765) and panuveitis (aHR = 3.386) increased the risk of developing keratopathies. Moreover, male sex was associated with a higher aHR than female sex for developing keratopathies in the study group.

Conclusions

The presence of uveitis significantly elevates the risk for developing keratopathy.

Autoimmunity in 2016

The number of peer-reviewed articles published during the 2016 solar year and retrieved using the "autoimmunity" key word remained stable while gaining a minimal edge among the immunology articles. Nonetheless, the quality of the publications has been rising significantly and, importantly, acquisitions have become available through scientific journals dedicated to immunology or autoimmunity. Major discoveries have been made in the fields of systemic lupus erythematosus, rheumatoid arthritis, autoimmunity of the central nervous system, vasculitis, and seronegative spondyloarthrithritides. Selected examples include the role of IL17-related genes and long noncoding RNAs in systemic lupus erythematosus or the effects of anti-pentraxin 3 (PTX3) in the treatment of this paradigmatic autoimmune condition. In the case of rheumatoid arthritis, there have been reports of the role of induced regulatory T cells (iTregs) or fibrocytes and T cell interactions with exciting implications. The large number of studies dealing with neuroimmunology pointed to Th17 cells, CD56(bright) NK cells, and low-level TLR2 ligands as involved in multiple sclerosis, along with a high salt intake or the micriobiome-derived Lipid 654. Lastly, we focused on the rare vasculitides to which numerous studies were devoted and suggested that unsuspected cell populations, including monocytes, mucosal-associated invariant T cells, and innate lymphoid cells, may be crucial to ANCA-associated manifestations. This brief and arbitrary discussion of the findings published in 2016 is representative of a promising background for developments that will enormously impact the work of laboratory scientists and physicians at an exponential rate.

A murine model of dry eye induced by topical administration of erlotinib eye drops

In the present study, the effects of erlotinib on mouse tear function and corneal epithelial tissue structure were investigated. Throughout the 3 weeks of treatment, no notable differences were observed in the body, eye or lacrimal gland weights of the control and experimental mice. However, in the experimental group, the tear volume and break‑up times of tear film were significantly lower following treatment with erlotinib compared with the control group. Corneal fluorescein staining in the experimental group revealed patchy staining, and the Lissamine green staining and inflammatory index were significantly higher in the experimental group at 3 weeks than in the control group. In the experimental group, the number of corneal epithelium layers increased significantly following treatment with erlotinib for 3 weeks and a significant increase in the number of vacuoles was observed compared with the control group. Treatment with erlotinib significantly increased the corneal epithelial cell apoptosis, and led to a significantly increased number of epithelial cell layers and increased keratin 10 expression. It also significantly reduced the number of conjunctival goblet cells. Transmission electron microscopy and scanning electron microscopy revealed that the corneal epithelial surface was irregular and there was a substantial reduction and partial loss of the microvilli in the experimental group. Mice treated with erlotinib also exhibited an increased protein expression of tumor necrosis factor‑α and decreased protein expression of phosphorylated‑epidermal growth factor receptor in the corneal epithelial cells. The topical application of erlotinib eye drops was revealed to induce dry eyes in mice. This is a novel method of developing a model of dry eyes in mice.

Clinical Effect of IRT-5 Probiotics on Immune Modulation of Autoimmunity or Alloimmunity in the Eye

Background: Although the relation of the gut microbiota to a development of autoimmune and inflammatory diseases has been investigated in various animal models, there are limited studies that evaluate the effect of probiotics in the autoimmune eye disease. Therefore, we aimed to investigate the effect of IRT-5 probiotics consisting of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus reuteri, Bifidobacterium bifidum, and Streptococcus thermophilus on the autoimmunity of uveitis and dry eye and alloimmunity of corneal transplantation. Methods: Experimental autoimmune uveitis was induced by subcutaneous immunization with interphotoreceptor-binding protein and intraperitoneal injection of pertussis toxin in C57BL/6 (B6) mice. For an autoimmune dry eye model, 12-weeks-old NOD.B10.H2^b mice were used. Donor cornea of B6 mice was transplanted into BALB/C mice. IRT-5 probiotics or phosphate buffered saline (PBS) were administered for three weeks immediately after induction of uveitis or transplantation. The inflammation score of the retinal tissues, dry eye manifestations (corneal staining and tear secretion), and graft survival were measured in each model. The changes of T cells were evaluated in drainage lymph nodes using fluorescence-activated cell sorting. Results: Retinal histology score in IRT-5 group of uveitis was lower than that in PBS group (p = 0.045). Ocular staining score was lower (p < 0.0001) and tear secretion was higher (p < 0.0001) in the IRT-5 group of NOD.B10.H2^b mice than that in the PBS group. However, the graft survival in the IRT-5 group was not different from those of PBS group. The percentage of regulatory T cells was increased in the IRT-5-treated dry eye models (p = 0.032). The percentage of CD8⁺IL-17^hi (p = 0.027) and CD8⁺ interferon gamma (IFNγ)^hi cells (p = 0.022) were significantly decreased in the IRT-5-treated uveitis models and the percentage of CD8⁺IFNγ^hi cells was markedly reduced (p = 0.036) in IRT-5-treated dry eye model. Conclusion: Our results suggest that administration of IRT-5 probiotics may modulate clinical manifestations of autoimmunity in the eye, but not on alloimmunity of corneal transplantation.

The Growing Need for Validated Biomarkers and Endpoints for Dry Eye Clinical Research

Purpose

Biomarkers with minimally invasive and reproducible objective metrics provide the key to future paradigm shifts in understanding of the underlying causes of dry eye disease (DED) and approaches to treatment of DED. We review biomarkers and their validity in providing objective metrics for DED clinical research and patient care.

Methods

The English-language literature in PubMed primarily over the last decade was surveyed for studies related to identification of biomarkers of DED: (1) inflammation, (2) point-of-care, (3) ocular imaging, and (4) genetics. Relevant studies in each group were individually evaluated for (1) methodological and analytical details, (2) data and concordance with other similar studies, and (3) potential to serve as validated biomarkers with objective metrics.

Results

Significant work has been done to identify biomarkers for DED clinical trials and for patient care. Interstudy variation among studies dealing with the same biomarker type was high. This could be attributed to biologic variations and/or differences in processing, and data analysis. Correlation with other signs and symptoms of DED was not always clear or present.

Conclusions

Many of the biomarkers reviewed show the potential to serve as validated and objective metrics for clinical research and patient care in DED. Interstudy variation for a given biomarker emphasizes the need for detailed reporting of study methodology, including information on subject characteristics, quality control, processing, and analysis methods to optimize development of nonsubjective metrics. Biomarker development offers a rich opportunity to significantly move forward clinical research and patient care in DED.

Overview

DED is an unmet medical need - a chronic pain syndrome associated with variable vision that affects quality of life, is common with advancing age, interferes with the comfortable use of contact lenses, and can diminish results of eye surgeries, such as cataract extraction, LASIK, and glaucoma procedures. It is a worldwide medical challenge with a prevalence rate ranging from 8% to 50%. Many clinicians and researchers across the globe are searching for better answers to understand the mechanisms related to the development and chronicity of DED. Though there have been many clinical trials for DED, few new treatments have emerged over the last decade. Biomarkers may provide the needed breakthrough to propel our understanding of DED to the next level and the potential to realize our goal of truly personalized medicine based on scientific evidence. Clinical trials and research on DED have suffered from the lack of validated biomarkers and less than objective and reproducible endpoints. Current work on biomarkers has provided the groundwork to move forward. This review highlights primarily ocular biomarkers that have been investigated for use in DED, discusses the methodologic outcomes in providing objective metrics for clinical research, and suggests recommendations for further work.