Interleukin-6 blockade in ocular inflammatory diseases

Exploring the role of the ocular surface in the lung-eye axis: Insights into respiratory disease pathogenesis

Chronic respiratory diseases (CRDs) represent a significant proportion of global health burden, with a wide spectrum of varying, heterogenic conditions largely affecting the pulmonary system. Recent advances in immunology and respiratory biology have highlighted the systemic impact of these diseases, notably through the elucidation of the lung-eye axis. The current review focusses on understanding the pivotal role of the lung-eye axis in the pathogenesis and progression of chronic respiratory infections and diseases. Existing literature published on the immunological crosstalk between the eye and the lung has been reviewed. The various roles of the ocular microbiome in lung health are also explored, examining the eye as a gateway for respiratory virus transmission, and assessing the impact of environmental irritants on both ocular and respiratory systems. This novel concept emphasizes a bidirectional relationship between respiratory and ocular health, suggesting that respiratory diseases may influence ocular conditions and vice versa, whereby this conception provides a comprehensive framework for understanding the intricate axis connecting both respiratory and ocular health. These aspects underscore the need for an integrative approach in the management of chronic respiratory diseases. Future research should further elucidate the in-depth molecular mechanisms affecting this axis which would pave the path for novel diagnostics and effective therapeutic strategies.

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

Aqueous humour interleukin-6 and vision outcomes with anti-vascular endothelial growth factor therapy

BACKGROUND

This analysis evaluated aqueous humour (AH) interleukin (IL)-6 concentrations and the association between AH IL-6 and visual outcomes in patients with neovascular age-related macular degeneration (nAMD) or diabetic macular oedema (DMO) receiving anti-vascular endothelial growth factor (VEGF) monotherapy.

METHODS

Post hoc analysis of the multicentre, double-masked, randomised HARBOR (NCT00891735) and READ-3 (NCT01077401) trials. HARBOR enrolled treatment-naïve nAMD patients. READ-3 enrolled treatment-naïve/previously treated DMO patients. HARBOR patients received ranibizumab 0.5 or 2.0 mg monthly or as needed; AH samples were collected at month 2, after two previous intravitreal injections. READ-3 patients received ranibizumab 0.5 or 2.0 mg as needed; AH samples were collected at baseline and months 3, 6, 9, and 12.

MAIN OUTCOME MEASURE

association between AH IL-6 concentrations and month 24 best-corrected visual acuity (BCVA).

RESULTS

In both trials (HARBOR, N = 36; READ-3, N = 137), patients with higher AH IL-6 concentrations had worse visual outcomes. HARBOR patients with low AH IL-6 concentrations at month 2 had a mean (95% CI) BCVA change at month 24 of +2.9 (-2.6, 8.3) letters, whereas patients with high AH concentrations had a mean (95% CI) BCVA change of -9.0 (-22.7, 4.7) letters. READ-3 patients with low AH concentrations at baseline had a mean (95% CI) BCVA change at month 12 of +9.3 (7.4, 11.3) letters, whereas patients with high AH concentrations had a mean (95% CI) BCVA change of +5.6 (2.2, 9.1) letters.

CONCLUSIONS

Higher IL-6 AH concentrations may predict suboptimal visual responses to anti-VEGF monotherapy in patients with nAMD/DMO.

Immunomodulatory effect of vitamin D supplementation on Behçet's disease patients: effect on nitric oxide and Th17/Treg cytokines production

INTRODUCTION

In the last decade, an immuno-modulatory effect of vitamin D supplementation have emerged as a potential therapeutic approach for some inflammatory and autoimmune diseases. As previously reported, vitamin D deficiency was strongly linked to several diseases as Behçet's disease (BD). BD is a chronic systemic inflammatory disorder with autoimmunity, genetic and environmental factors involvement. The aim of our current study is to set up a new therapeutic strategy in BD, combining conventional therapy and vitamin D supplementation.

MATERIALS AND METHODS

Blood samples were collected from active and inactive BD patients and healthy controls (HC) to evaluate 25(OH) vitamin D levels using an electrochemiluminescence method. All deficient and insufficient vitamin D BD patients' were supplemented with vitamin D3 (CHOLECALCIFEROL, 200 000 UI/1 ml). In this context, NO, IL-17A and IL-10 levels were evaluated in patients and HC in vivo and ex vivo using Griess and ELISA methods respectively.

RESULTS

Before supplementation, we noted with interest that BD patients had vitamin D deficiency, associated with elevated in vivo and ex vivo NO and IL-17A levels compared to HC. Conversely, low IL-10 levels were observed in the same BD patients in comparison to HC. Interestingly, restored vitamin D status in supplemented BD patients was related to the decreased NO levels. In the same way, the IL-10/IL-17A ratio was improved.

CONCLUSIONS

Collectively, our data suggest that vitamin D supplementation in combination with conventional treatments has a beneficial effect and could constitute a good therapeutic candidate for alleviating inflammatory responses during Behçet disease.

Relationship between vitreous interleukin-6 levels and vitreous particles findings on widefield optical coherence tomography in posterior uveitis

PURPOSE

To investigate relationship between vitreous interleukin-6 levels and vitreous particles findings on widefield optical coherence tomography in posterior uveitis.

METHODS

This retrospective study examined vitreous inflammatory cells (hyperreflective particles) of posterior uveitis on widefield optical coherence tomography (WOCT). We examined the number of hyperreflective particles (possibility of vitreous inflammatory cells) observed on WOCT and the correlations with interleukin-6 (IL-6) levels. The relationship between vitreous IL-6 levels and image findings from WOCT from 37 eyes (34 patients) with posterior uveitis were analyzed. Mean patient age was 63.4±15.7 years. (Mean± standard deviation) IL-6 concentration in vitreous humor was 79.9±7380.9 pg/mL Uveitis was infectious in 9 cases and non-infectious in 28 cases with multiplex polymerase chain reaction system. We measured the number and size of vitreous cells in the posterior vitreous, defined as the space between the upper vitreous and the internal limiting membrane on WOCT at the macular, upper, and lower regions. Image analysis software was also used for cell counting.

RESULTS

A strong correlation was seen between human and software counts. Pearson's correlation coefficient (PCC) was performed to compare categorial variables (on macular +0.866; upper cavity +0.713; lower cavity +0.568; total vitreous cavity +0.834; P<0.001 each). IL-6 levels correlated with both vitreous cell counts and cell counts observed on macular WOCT (human-counted group +0.339, P = 0.04; software-counted group +0.349, P = 0.03). Infectious uveitis showed higher IL-6 levels (P = 0.016) and high cell counts compared with non-infectious uveitis (P = 0.04).

CONCLUSIONS

Vitreous number of hyperreflective particles (cells) findings on WOCTcorrelated well with human and software cell counts. Vitreous cells findings on WOCT also correlated with IL-6 concentrations on macular.

Update on the systemic management of noninfectious uveitis in children and adolescents

Noninfectious uveitis (NIU) in children and adolescents is a rare but treatable cause of visual impairment in children. Treatments for pediatric NIU and their side effects, along with the risks of vision loss and the need for long-term disease monitoring, pose significant challenges for young patients and their families. Treatment includes local and systemic approaches and this review will focus on systemic therapies that encompass corticosteroids, conventional synthetic disease-modifying antirheumatic drugs (csDMARD), and biological disease-modifying antirheumatic drugs (bDMARD). Treatment is generally planned in a stepwise approach. Methotrexate is well-established as the preferential csDMARD in pediatric NIU. Adalimumab, an antitumor necrosis factor (TNF) agent, is the only bDMARD formally approved for pediatric NIU and has a good safety and efficacy profile. Biosimilars are gaining increasing visibility in the treatment of pediatric NIU. Other bDMARD with some evidence in literature for the treatment of pediatric NIU include infliximab, tocilizumab, abatacept, rituximab and, more recently, Janus kinase inhibitors. Important aspects of managing children on these systemic therapies include vaccination issues, risk of infection, and psychological distress. Also, strategies need to address regarding primary nonresponse/secondary loss of response to anti-TNF treatment, biological switching, and monitoring regimens for these drugs. Optimal management of pediatric uveitis involves a multidisciplinary team, including specialist pediatric uveitis and rheumatology nurses, pediatric rheumatologists, psychological support, orthoptic and optometry support, and play specialists.

Lipid nanoparticle-mediated delivery of mRNA into the mouse and human retina and other ocular tissues

Purpose

Lipid nanoparticles (LNPs) show promise in their ability to introduce mRNA to drive protein expression in specific cell types of the mammalian eye. Here, we examined the ability of mRNA encapsulated in lipid nanoparticles (LNPs) with two distinct formulations to drive gene expression in mouse and human retina and other ocular tissues.

Methods

We introduced mRNA carrying LNPs into two biological systems. Intravitreal injections were tested to deliver LNPs into the mouse eye. Human retinal pigment epithelium (RPE) and retinal explants were used to assess mRNA expression in human tissue. We analyzed specificity of expression using histology, immunofluorescence, and imaging.

Results

In mice, mRNAs encoding GFP and ciliary neurotrophic factor (CNTF) were specifically expressed by Müller glia and retinal pigment epithelium (RPE). Acute inflammatory changes measured by microglia distribution (Iba-1) or interleukin-6 (IL-6) expression were not observed 6 hours post-injection. Human RPE also expressed high levels of GFP. Human retinal explants expressed GFP in cells with apical and basal processes consistent with Müller glia and in perivascular cells consistent with macrophages.

Conclusions

We demonstrated the ability to reliably transfect subpopulations of retinal cells in mice eye tissues in vivo and in human ocular tissues. Of significance, intravitreal injections were sufficient to transfect the RPE in mice. To our knowledge we demonstrate delivery of mRNA using LNPs in human ocular tissues for the first time.

Interleukin-6 in retinal diseases: From pathogenesis to therapy

Interleukin-6 (IL-6) is a pleiotropic cytokine that participates in immunomodulation, inflammation, increases vascular permeability, hematopoiesis, and stimulates cell proliferation, among other biological processes. It exerts effects primarily through the classic and trans-signaling pathways. Many studies have demonstrated that IL-6 plays a critical role in the development of retinal diseases including diabetic retinopathy, uveitis, age-related macular degeneration, glaucoma, retinal vein occlusion, central serous chorioretinopathy and proliferative vitreoretinopathy. Thus, the progressive development of drugs targeting IL-6 and IL-6 receptor may play a role in the treatment of multiple retinal diseases. In this article, we comprehensively review the IL-6's biological functions of and its mechanisms in the pathogenesis of various retinal diseases. Furthermore, we summarize the drugs targeting IL-6 and its receptor and prospect their potential application in retinal diseases, hoping to provide new ideas for the treatment of retinal diseases.

Recurrent Scedosporium apiospermum Cutaneous Infection in a Patient with Rheumatoid Arthritis: The Potent Role of IL-6 Signaling Pathway Blockade: A Case-Based Review

Rheumatoid arthritis (RA) patients deal with a higher risk of bacterial and fungal infections compared to the general population because of their dysregulated immune system as well as the immunosuppressive therapy they usually receive. Scedosporium spp. is a fungal pathogen responsible for cutaneous, lung, central nervous system, and eye infections, mostly in immunocompromised patients, leading to death in disseminated cases. We report the case of an 81-year-old woman with rheumatoid arthritis treated with steroids and an IL-6 inhibitor who was diagnosed with scedosporiosis of the upper limb. She was treated with voriconazole for one month, which was discontinued due to adverse events, and when scedosporiosis relapsed, she switched to itraconazole. We also reviewed the current literature on RA patients presenting with Scedosporium infections. Early and accurate diagnosis of scedosporiosis has therapeutic and prognostic implications, as traditionally this fungus is resistant to commonly used antifungals. Clinical alertness regarding uncommon infections, including fungal, in patients with autoimmune diseases on immunomodulatory agents is essential for effective treatment.

Mechanisms of macular edema

Macular edema is the pathological accumulation of fluid in the central retina. It is a complication of many retinal diseases, including diabetic retinopathy, retinal vascular occlusions and uveitis, among others. Macular edema causes decreased visual acuity and, when chronic or refractory, can cause severe and permanent visual impairment and blindness. In most instances, it develops due to dysregulation of the blood-retinal barrier which permits infiltration of the retinal tissue by proteins and other solutes that are normally retained in the blood. The increase in osmotic pressure in the tissue drives fluid accumulation. Current treatments include vascular endothelial growth factor blockers, corticosteroids, and non-steroidal anti-inflammatory drugs. These treatments target vasoactive and inflammatory mediators that cause disruption to the blood-retinal barrier. In this review, a clinical overview of macular edema is provided, mechanisms of disease are discussed, highlighting processes targeted by current treatments, and areas of opportunity for future research are identified.

In Silico Prediction of the Bioactive Profile and Metabolites of Satureja nepeta in Diseases Related to the Excessive Production of Interleukin-6

Inflammatory bowel diseases are caused by an abnormal reaction of the immune system, which becomes hyperactive because the mechanisms responsible for regulating it get out of control. For an effective immune response, many proinflammatory cytokines are secreted, particularly interleukin-6 (IL-6) keystone cytokine inflammation. Many synthetic and natural compounds targeting IL-6 have been studied. The genus Satureja of the Lamiaceae family is generally known for its many virtues, in particular anti-inflammatory properties. However, the mechanism of action is unclear. This study aims to predict the impact of characterized bioactive molecules of Moroccan Satureja nepeta in the potential control of inflammatory response mediated by IL-6 cytokine. A list of 9 previously characterized natural compounds of S. nepeta was compiled, and a list of 6 potential protein targets involved in intestinal inflammation was made. The 2 lists of natural compound-target proteins were analyzed by the STITCH software (http://stitch.embl.de/) to develop protein-compound and protein-protein interaction networks (PPINs). An ontological enrichment (GO) analysis was performed by the Clue GO plugin to evaluate the PPIN generated by STITCH; finally, the molecular docking to predict the mode underlying the anti-inflammatory effects. STITCH results revealed direct and indirect interactions of S. nepeta chemical compounds with a key protein target IL-6. The array results by ClueGO showed that most compounds involved in the regulation of several biological processes related to IL-6 such as inflammation apoptosis, cell differentiation, and metabolic regulation. The targets directly related to IL-6 have been used for molecular docking. Quercetin, catechin, and gallic acid have a strong affinity with the IL-6 receptor (respectively −7.1; −6.1; −5.3). This study strongly suggests that the bioactive compounds of S. nepeta could constitute a new therapeutic alternative in the treatment of diseases related to IL-6. However, to validate the results obtained in this work, it is necessary to explore the mechanism of action of potential bioactive molecules by experimentation.

Recent advances in nanomaterials-based optical sensors for detection of various biomarkers (inorganic species, organic and biomolecules)

This review briefly emphasizes the different detection approaches (electrochemical sensors, chemiluminescence, surface-enhanced Raman scattering), functional nanostructure materials (quantum dots, metal nanoparticles, metal nanoclusters, magnetic nanomaterials, metal oxide nanoparticles, polymer-based nanomaterials, and carbonaceous nanomaterials) and detection mechanisms. Further, this review emphasis on the integration of functional nanomaterials with optical spectroscopic techniques for the identification of various biomarkers (nucleic acids, glucose, uric acid, oxytocin, dopamine, ascorbic acid, bilirubin, spermine, serotonin, thiocyanate, Pb²⁺ , Cu²⁺ , Hg²⁺ , F^- , peptides, and cancer biomarkers (mucin 1, prostate specific antigen, carcinoembryonic antigen, CA15-3, human epidermal growth factor receptor 2, C-reactive protein, and interleukin-6). Analytical characteristics of nanomaterials-based optical sensors are summarized in Tables, providing the insights of nanomaterials-based optical sensors for biomarkers detection. Finally, the opportunities and challenges of nanomaterials-based optical analytical approaches for the detection of various biomarkers (inorganic, organic, biomolecules, peptides and proteins) are discussed.

Analysis of the Cytokine Expression in the Aqueous Humor of Individuals with BRVO-Associated Macular Edema

Purpose

This study aimed to determine the expression levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in the aqueous humor of patients with macular edema (ME) caused by branch retinal vein occlusion (BRVO), as well as to investigate the relationship between the cytokines as mentioned earlier and best-corrected visual acuity (BCVA), ME, and the degree of ME from the molecular level.

Methods

In a prospective observational study, fluorescein fundus angiography (FFA) and optical coherence tomography (OCT) were used to classify 58 patients with non-ischemic BRVO-ME into three groups according to the degree of ME: 14-mild, 17-moderate, and 27-severe. The specific concentration of IL-6, VEGF, ICAM-1, and VCAM-1 in the aqueous humor was detected using the BD CSCanto™ II Flow Cytometer (US). Spearman or Pearson correlation analysis was used to test the correlation between the levels of BCVA and severity of ME and the expression levels of IL-6, VEGF, ICAM-1, and VCAM-1 in the aqueous humor.

Results

According to the obtained data, BCVA did not correlate with the severity of ME, and these four cytokines expression levels in patients' aqueous humor (P > 0.05). Moreover, BCVA did not correlate with mild, moderate, or severe ME as well (P > 0.05). However, the levels of these four cytokines were correlated with the severity of the ME. These underlined cytokines were linked to the mild, moderate, and severe degrees of ME. VEGF was also significantly correlated (r > 0.8, P < 0.0001) with the severity of ME.

Conclusions

This study suggests that the severity of ME in BRVO-ME patients is significantly correlated with the expression levels of IL-6, VEGF, ICAM-1, and VCAM-1 in the aqueous humor. Lowering the level of disease-associated cytokines may potentially reduce the degree of ME. Therefore, an in-depth study of the levels and the relationship may provide some evidence for the pathogenesis, treatment, and prevention of BRVO-ME.

Do Oral Pathogens Inhabit the Eye and Play a Role in Ocular Diseases?

Fascinatingly, the immune-privileged healthy eye has a small unique population of microbiota. The human microbiome project led to continuing interest in the ocular microbiome. Typically, ocular microflorae are commensals of low diversity that colonize the external and internal sites of the eye, without instigating any disorders. Ocular commensals modulate immunity and optimally regulate host defense against pathogenic invasion, both on the ocular surface and neuroretina. Yet, any alteration in this symbiotic relationship culminates in the perturbation of ocular homeostasis and shifts the equilibrium toward local or systemic inflammation and, in turn, impaired visual function. A compositional variation in the ocular microbiota is associated with surface disorders such as keratitis, blepharitis, and conjunctivitis. Nevertheless, innovative studies now implicate non-ocular microbial dysbiosis in glaucoma, age-related macular degeneration (AMD), uveitis, and diabetic retinopathy. Accordingly, prompt identification of the extra-ocular etiology and a methodical understanding of the mechanisms of invasion and host-microbial interaction is of paramount importance for preventative and therapeutic interventions for vision-threatening conditions. This review article aims to explore the current literature evidence to better comprehend the role of oral pathogens in the etiopathogenesis of ocular diseases, specifically AMD.

Effects of Pereskia aculeate Miller Petroleum Ether Extract on Complete Freund’s Adjuvant-Induced Rheumatoid Arthritis in Rats and its Potential Molecular Mechanisms

Objective: To investigate the therapeutic effect of petroleum ether extract of P. aculeate Miller (PEEP) on rheumatoid arthritis (RA).

Methods:In vitro: The Cell Counting Kit-8 (CCK-8) was used to detect cell activity and select the optimal concentration of the extract; the effective site was screened by nitric oxide (NO) colorimetric method and Q-PCR method; the expression of p38, p-p38, p-MK2, and Tristetraprolin (TTP) in RAW 264.7 cells were detected by Western blot. In vivo: The rat model was established by complete Freund’s adjuvant (CFA). The different doses of PEEP on CFA rats were observed with life status, paw swelling, spleen index, X-ray, Hematoxylin eosin (HE) staining; the secretion of Tumor necrosis factor α (TNF-α), interleukin-6 (IL-6) and Prostaglandin E2 (PGE2) were detected by Enzyme linked immunosorbent assay (ELISA); the expressions of p38, p-p38, p-MK2, and TTP in the ankle joints of CFA rats were detected by Western blot.

Result:In vitro: PEEP, Ethyl Acetate Extract of P. aculeate Miller (EEEP), N-butanol Extract of P. aculeate Miller (BEEP) have no toxic effects on RAW264.7 macrophages. PEEP, EEEP, and BEEP reduce the secretion of NO in RAW264.7 cells induced by lipopolysaccharide (LPS), only PEEP significantly inhibited the mRNA expression levels of inflammatory factors TNF-α and IL-6; PEEP-dependently reduce the secretion of TNF-α and IL-6, decrease the expression of p-p38 and p-MK2, and the level of TTP phosphorylation in LPS-induced RAW264.7 cells. In vivo: PEEP improve the living conditions of CFA rats, reduce foot swelling, spleen index, bone surface erosion and joint space narrowing; reduce the formation of synovial cells, inflammatory cells and pannus in the foot and ankle joints. PEEP reduce the secretion of TNF-α, IL-6, PGE2 in rat serum, downregulate the expression of p-p38 and p-MK2 in the ankle joint, and reduce the phosphorylation of TTP.

Conclusion: PEEP improve the living conditions of CFA rats, reduce the degree of foot swelling, protect immune organs, reduce inflammatory cell infiltration, cartilage damage, pannus formation, reduce inflammation and RA damage. The mechanism through regulating the signal pathway of p38 mitogen-activated protein kinase (p38/MAPK), which reduces the release of TNF-α, IL-6, and PGE2 in the serum.

Cytokines, chemokines and growth factors profile in human aqueous humor in idiopathic uveitis

To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.

Inflammation in obesity, diabetes, and related disorders

Obesity leads to chronic, systemic inflammation and can lead to insulin resistance (IR), β-cell dysfunction, and ultimately type 2 diabetes (T2D). This chronic inflammatory state contributes to long-term complications of diabetes, including non-alcoholic fatty liver disease (NAFLD), retinopathy, cardiovascular disease, and nephropathy, and may underlie the association of type 2 diabetes with other conditions such as Alzheimer's disease, polycystic ovarian syndrome, gout, and rheumatoid arthritis. Here, we review the current understanding of the mechanisms underlying inflammation in obesity, T2D, and related disorders. We discuss how chronic tissue inflammation results in IR, impaired insulin secretion, glucose intolerance, and T2D and review the effect of inflammation on diabetic complications and on the relationship between T2D and other pathologies. In this context, we discuss current therapeutic options for the treatment of metabolic disease, advances in the clinic and the potential of immune-modulatory approaches.

Anti-inflammatory Effects of GTE in Eye Diseases

Ocular inflammation is a common complication of various eye diseases with wide consequences from irritations to potentially sight-threatening complications. Green tea is a popular beverage throughout the world. One of the proven health benefits of consuming green tea extract (GTE) is anti-inflammation. Catechins are the biologically active constituents of GTE. In in vitro and in vivo studies, GTE and catechins present inhibition of inflammatory responses in the development of ocular inflammation including infectious, non-infectious or autoimmune, and oxidative-induced complications. Research on the ocular inflammation in animal models has made significant progress in the past decades and several key disease mechanisms have been identified. Here we review the experimental investigations on the effects of GTE and catechins on various ocular inflammation related diseases including glaucoma, age-related macular degeneration, uveitis and ocular surface inflammation. We also review the pharmacokinetics of GTE constituents and safety of green tea consumption. We discuss the insights and perspectives of these experimental results, which would be useful for future development of novel therapeutics in human.

Epigenetic Modifications and Therapy in Uveitis

Uveitis is a sight-threatening intraocular inflammation, and the exact pathogenesis of uveitis is not yet clear. Recent studies, including multiple genome-wide association studies (GWASs), have identified genetic variations associated with the onset and progression of different types of uveitis, such as Vogt–Koyanagi–Harada (VKH) disease and Behcet’s disease (BD). However, epigenetic regulation has been shown to play key roles in the immunoregulation of uveitis, and epigenetic therapies are promising treatments for intraocular inflammation. In this review, we summarize recent advances in identifying epigenetic programs that cooperate with the physiology of intraocular immune responses and the pathology of intraocular inflammation. These attempts to understand the epigenetic mechanisms of uveitis may provide hope for the future development of epigenetic therapies for these devastating intraocular inflammatory conditions.

Efficacy and safety of tocilizumab in Behçet's syndrome with refractory arterial lesions: A single-centre observational cohort study in China

Objective

The aim of this observational cohort study was to assess the effectiveness and safety of the IL-6-receptor inhibitor tocilizumab (TCZ) in Behçet’s syndrome (BS) with refractory arterial involvement.

Methods

Ten patients admitted to the Rheumatology and Immunology Department of Peking University People’s Hospital between January 2014 and December 2019 were enrolled. The enrolled patients met the BS international criteria and exhibited severe arterial impairments. Refractory arterio-BS was diagnosed based on objective vascular symptoms unexplainable by other known illnesses, and resistance to traditional immunosuppressants and glucocorticoids after 12 weeks. Patients received 8 mg/kg TCZ infusions every 4 weeks for ≥24 weeks, with simultaneous continuation of immunosuppressants and glucocorticoids. Clinical and imaging data were assessed before and after TCZ treatment.

Results

The enrolled patients were men aged 44.3 (10.5) years; the median disease duration was 186.5 (45.7) months, and the average age of arterial impairment onset was 38.7 (12.9) years. The following trends were observed: improvement and maintenance of symptoms after the 26.8 (7.2)-month follow-up, n = 9; complete remission, n = 6; partial response, n = 3; immunosuppressant dose reduction, n = 4; radiologic improvement of arterial lesions, n = 4; and TCZ discontinuation owing to enlarged abdominal aortic aneurysm relapse, n = 1. The average daily glucocorticoid dose reduced from 54.5 (20.6) to 8.3 (3.6) mg/d (P < 0.001), while the median ESR and CRP values reduced from 50 (2–82) mm/h and 32.9 (2.1–62.3) mg/dl to 4 (1–10) mm/h and 2.9 (0.2–12.1) mg/dl, respectively (P < 0.001). No TCZ-associated side effects were noted.

Conclusion

TCZ proved to be safe and effective for refractory arterial lesions in BS, with a steroid- and immunosuppressant-sparing benefit.

Inflammatory mediators in diabetic retinopathy: Deriving clinicopathological correlations for potential targeted therapy

The role of inflammation in diabetic retinopathy (DR) is well-established and dysregulation of a large number of inflammatory mediators is known. These include cytokines, chemokines, growth factors, mediators of proteogenesis, and pro-apoptotic molecules. This para-inflammation as a response is not directed to a particular pathogen or antigen but is rather directed toward the by-products of the diabetic milieu. The inflammatory mediators take part in cascades that result in cellular level responses like neurodegeneration, pericyte loss, leakage, capillary drop out, neovascularization, etc. There are multiple overlaps between the inflammatory pathways occurring within the diabetic retina due to a large number of mediators, their varied sources, and cross-interactions. This makes understanding the role of inflammation in clinical manifestations of DR difficult. Currently, mediator-based therapy for DR is being evaluated for interventions that target a specific step of the inflammatory cascade. We reviewed the role of inflammation in DR and derived a simplified clinicopathological correlation between the sources and stimuli of inflammation, the inflammatory mediators and pathways, and the clinical manifestations of DR. By doing so, we deliberate mediator-specific therapy for DR. The cross-interactions between inflammatory mediators and the molecular cycles influencing the inflammatory cascades are crucial challenges to such an approach. Future research should be directed to assess the feasibility of the pathology-based therapy for DR.

Effect of preoperative eyedrops on cytokine concentrations in aqueous humor of patients undergoing femtosecond laser-assisted cataract surgery

PURPOSE

To compare the anti-inflammatory activity of preoperatively applied eyedrops, as determined by cytokine concentrations in aqueous humor collected during surgery in patients undergoing femtosecond laser-assisted cataract surgery.

METHODS

A total of 120 patients undergoing femtosecond laser-assisted cataract surgery were randomly assigned to four groups of 30 patients each. Groups were administered 0.1% fluorometholone eyedrops, 0.45% ketorolac tromethamine eyedrops, both 0.1% fluorometholone and 0.45% ketorolac tromethamine eyedrops, or no eyedrops. Eyedrops were instilled 1 h, 20 min, and just before surgery. After anterior capsulotomy and nuclear fragmentation using a femtosecond laser, 0.1 cc aqueous humor was obtained using a needle and syringe. Cytokine and prostaglandin E₂ (PGE₂) concentrations were quantitatively determined.

RESULTS

The 120 patients included 59 men and 61 women, of mean age 65.02 years. The mean interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations after treatment did not differ significantly in the four groups. The average interleukin-8 (IL-8) concentrations were significantly lower in the fluorometholone (4.80 pg/mL), ketorolac tromethamine (4.84 pg/mL), and fluorometholone + ketorolac tromethamine (4.68 pg/mL) groups than in the control group (6.83 pg/mL). Furthermore, the average PGE₂ concentrations were significantly lower in the ketorolac tromethamine (270.04 pg/mL) and fluorometholone + ketorolac tromethamine (239.00 pg/mL) groups, but not in the fluorometholone (393.16 pg/mL) group, than in the control group (472.36 pg/mL).

CONCLUSION

Preoperative fluorometholone instillation reduced IL-8, and ketorolac tromethamine instillation reduced IL-8 and PGE₂, in aqueous humor of patients undergoing femtosecond laser surgery, with the combination of both eyedrops being more effective than either alone.

TRIAL REGISTRATION

KCT0005717.

KSI-301: antibody biopolymer conjugate in retinal disorders

KSI-301 is a new intravitreal anti-vascular endothelial growth factor (VEGF) antibody biopolymer conjugate under investigation for the treatment of age-related macular degeneration (AMD), diabetic macular oedema (DME) and retinal vein occlusion (RVO). Preclinical and early clinical trials so far have shown promising results in retinal vascular diseases. When using anti-VEGF agents for treatment of retinal disorders, the frequency of injections and follow-up visits has increased the treatment burden, greatly affecting the treatment outcome. There are new anti-VEGF agents in the horizon with extended duration of action, durability, safety profile and efficacy, which seem to address the above issues. PubMed search and Medline search were performed on newer anti-VEGF agents, KSI-301, antibody biopolymer conjugate in retina, KODIAK KSI-301, DAZZLE study, GLEAM study, GLIMMER study, GLOW study and BEACON study. This review article showcases the biophysical properties and ongoing trials related to KSI-301. Moreover, we discuss the efficacy and safety profile of KSI-301 on the basis of the results of available trials.

Differential Diagnosis of Sjögren Versus Non-Sjögren Dry Eye Through Tear Film Biomarkers

PURPOSE

Systemic implications necessitate the identification of dry eye patients with Sjögren syndrome (SS). This study aims to explore the utility of tear MUC5AC and inflammatory cytokine levels in the differential diagnosis of SS-related dry eye.

METHODS

A prospective, observational, case-control study was conducted on 62 patients (those with a definitive diagnosis of SS dry eye, non-SS dry eye, and age-matched healthy controls with no dry eye). Clinical evaluations included the following tests in the order listed here: noninvasive tear break-up time, osmolarity, tear sampling, Schirmer test without anesthesia, and ocular surface staining (lissamine green for conjunctiva and fluorescein for cornea). Tear MUC5AC levels were assessed with enzyme-linked immunosorbent assay, and cytokines [interferon-gamma, tumor necrosis factor alpha, interleukin (IL)-6, IL-17a, IL-1β, IL-8, IL-10, and IL-12p70] were measured using a Luminex assay in a masked fashion.

RESULTS

The Bulbar conjunctival lissamine green staining score was significantly greater in patients or controls with SS versus non-SS dry eye. This greater conjunctival staining was associated with a reduction in tear MUC5AC (B = -17.8 ng/mL, 95% confidence interval = -31.8 to -3.9, P = 0.01). Among the tear cytokines, a significant association was found between IL-8 levels (hazard ratio [HR] = 1.002, 95% confidence interval = 1.000-1.003, P = 0.03) and SS diagnosis. When patients were stratified based on tear MUC5AC levels, significantly increased tear IL-8 levels were detected in patients with SS dry eye but not with non-SS dry eye, in comparison with healthy controls.

CONCLUSIONS

Tear levels of goblet cell-specific MUC5AC combined with IL-8 can potentially serve as a useful biomarker for differential diagnosis of SS dry eye from non-SS dry eye.

Imbalance in the Levels of Angiogenic Factors in Patients with Acute and Chronic Central Serous Chorioretinopathy

BACKGROUND

The pathogenesis of central serous chorioretinopathy (CSC) remains a subject of intensive research. We aimed to determine correlations between plasma levels of selected angiogenic factors and different forms of CSC.

METHODS

Eighty patients were enrolled in the study including 30 with a chronic form of CSC, 30 with acute CSC, and 20 controls. Presence of active CSC was determined by fluorescein angiography (FA), indocyanine green angiography (ICGA), and swept-source optical coherence tomography (SS-OCT). Plasma concentrations of angiopoietin-1, endostatin, fibroblast growth factor, placental growth factor (PlGF), platelet-derived growth factor (PDGF-AA), thrombospondin-2, vascular endothelial growth factor (VEGF), VEGF-D, and pigment epithelium-derived factor were measured, and the results were compared between groups. Additionally, mean choroidal thickness (CT) was measured in all patients.

RESULTS

Levels of angiopoietin-1 (p = 0.008), PlGF (p = 0.045), and PDGF-AA (p = 0.033) differed significantly between the three groups. Compared with the controls, VEGF (p = 0.024), PlGF (p = 0.013), and PDGF-AA (p = 0.012) were downregulated in the whole CSC group, specifically PDGF-AA (p = 0.002) in acute CSC and angiopoietin-1 (p = 0.007) in chronic CSC. An inverse correlation between mean CT and VEGF levels was noted in CSC patients (rho = -0.27, p = 0.044).

CONCLUSIONS

Downregulated angiopoietin-1, VEGF, PDGF-AA, and PlGF levels may highlight the previously unknown role of the imbalanced levels of proangiogenic and antiangiogenic factors in the pathogenesis of CSC. Moreover, downregulated VEGF levels may suggest that choroidal neovascularization in CSC is associated with arteriogenesis rather than angiogenesis.

Altered plasma cytokine levels in acute and chronic central serous chorioretinopathy

PURPOSE

To evaluate plasma levels of selected cytokines and investigate their correlation with choroidal thickness (CT) in patients with acute and chronic central serous chorioretinopathy (CSC).

METHODS

We enrolled 30 patients with acute CSC, 30 patients with chronic CSC and 20 controls. Plasma concentrations of 12 cytokines, interleukins IL-8, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10 and IL-12 p70, granulocyte-macrophage colony-stimulating factor, interferon-γ, tumour necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), were measured using multiplex immunoassays. Differences in cytokine levels between groups were assessed. We also investigated correlations between cytokine levels and CT using swept-source optical coherence tomography, as well as an association between plasma cytokine profile and systemic hypertension.

RESULTS

We noted differences in IL-6 (p = 0.005), IL-10 (p = 0.03), IL-12 p70 (p = 0.028) and VEGF (p = 0.029) levels between groups. Pro-inflammatory IL-12 p70 and multidirectional IL-10 cytokines were upregulated, while pro-angiogenic VEGF was downregulated in chronic CSC as compared with controls (p = 0.005, p = 0.025 and p = 0.027, respectively). Interleukin-6 (IL-6) was upregulated in acute and chronic CSC (p = 0.030 and p = 0.005, respectively). Interleukin-5 (IL-5), IL-6 and IL-12 levels correlated with mean CT in acute CSC (p = 0.008, p = 0.003 and p = 0.044, respectively), while IL-8, IL-6 and TNF-α plasma levels correlated with hypertension in chronic CSC (p = 0.005, p = 0.033 and p = 0.001, respectively).

CONCLUSION

We provided new evidence for the possible role of plasma cytokines in the pathogenesis of CSC. Our results suggest that IL-6 may be important in the pathophysiology of acute and chronic CSC. The association between inflammatory response and hypertension in patients with CSC was also confirmed.

Development of a zebrafish screening model for diabetic retinopathy induced by hyperglycemia: Reproducibility verification in animal model

This study aimed at creating a zebrafish screening model for diabetic retinopathy, and evaluated the effects of aflibercept, which is being used to treated diabetic retinopathy. A morphological change occurred at 160 mM of glucose. The survival and hatching rate decreased in a dose-dependent manner. In the 130 mM glucose group, the retinal vessel diameter was more than double that in the normal group. The zebrafish embryo morphology changed in 200 μg/mL and 400 μg/mL at aflibercept. The survival and hatching rate decrease at 400 μg/mL. Aflibercept 100 μg/mL was a nontoxic and effective dose for the zebrafish diabetic retinopathy model. The expression of diabetic retinopathy inflammatory markers was increased in hyperglycemia. But the inflammation was improved by aflibercept in the zebrafish eye. In a zebrafish diabetic retinopathy model, the diameters of retinal vessels were reduced after treatment with aflibercept, and molecular biological and histopathological efficacy was confirmed. This model can serve for screening of new drug candidates for treatment of in diabetic retinopathy.

Eye on the Enigmatic Link: Dysbiotic Oral Pathogens in Ocular Diseases; The Flip Side

Mouth and associated structures were regarded as separate entities from the rest of the body. However, there is a paradigm shift in this conception and oral health is now considered as a fundamental part of overall well-being. In recent years, the subject of oral-foci of infection has attained a resurgence in terms of systemic morbidities while limited observations denote the implication of chronic oral inflammation in the pathogenesis of eye diseases. Hitherto, there is a paucity for mechanistic insights underlying the reported link between periodontal disease (PD) and ocular comorbidities. In light of prevailing scientific evidence, this review article will focus on the understudied theme, that is, the impact of oral dysbiosis in the induction and/or progression of inflammatory eye diseases like diabetic retinopathy, scleritis, uveitis, glaucoma, age-related macular degeneration (AMD). Furthermore, the plausible mechanisms by which periodontal microbiota may trigger immune dysfunction in the Oro-optic-network and promote the development of PD-associated AMD have been discussed.

Interleukin-6 promotes migration and extracellular matrix synthesis in retinal pigment epithelial cells

Proliferative vitreoretinopathy (PVR) is the most common cause of surgical failure in the rhegmatogenous retinal detachment (RD) treatment. Retinal pigment epithelial (RPE) cell proliferation, migration, and the synthesis of extracellular matrix (ECM) are intrinsic to the formation of a PVR membrane. High level of interleukin-6 (IL-6) has been found in the vitreous of PVR patients, while the role of IL-6 in RPE cells remaining further characterized. In the present study, we evaluated the potential regulatory effects of IL-6 on cell migration, ECM components, and transforming growth factor β2 (TGF-β2) expression in RPE cells. Furthermore, cell counting kit-8 (CCK‑8) assay was used to investigate cell proliferation activity. We found that IL-6 promoted fibronectin (Fn) and type I collagen (COL-1), TGF-β2 expression in RPE cells, also stimulate RPE cell migration effectively. Moreover, the induction of IL-6 activated the Janus kinase/signal transducers and activators of transcription (JAK/STAT3) and the nuclear factor kappa-B (NF-κB) signaling pathways significantly. Simultaneously, both JAK/STAT3 and NF-κB pathways inhibitors, WP1066 and BAY11-7082, alleviated IL-6-induced biological effects, respectively. However, it was noted that IL-6 had little effect on α-smooth muscle actin (α-SMA) expression. Collectively, our results reveal that IL-6 promotes RPE cell migration and ECM synthesis via activating JAK/STAT3 and NF-κB signaling pathways, which may play a crucial role in PVR formation.

Tocilizumab versus Rituximab in Patients with Moderate to Severe Steroid-resistant Graves' Orbitopathy

Introduction: To describe the efficacy of tocilizumab in patients with Graves' orbitopathy resistant or dependent to steroids and compare to rituximab treated patients.Patients and Methods: Graves's orbitopathy response was considered as decrease of at least 2 points of the CAS.Results: Twenty-one patients were included, 7 patients were treated with tocilizumab and 14 with rituximab. The primary was achieved in all 7 patients (100%) on tocilizumab and 9 out of 14 patients on (64%) rituximab (p = .17). Mean change in CAS was consistent with a decrease of 3.3 ± 0.5 points in patients on tocilizumab versus 2.5 ± 1.9 in patients on rituximab (p = .07). One patient on tocilizumab (14%) and 4 patients (29%) on rituximab experienced significant relapse during the follow-up. The difference in relapse-free survival was not significant in patients on tocilizumab (10.8 ± 4 months) compared with rituximab (17.88 ± 3.66).Conclusion: We showed a significant improvement in the CAS, visual acuity, diplopia, and proptosis with both tocilizumab and rituximab.

Advances in steroid sparing medical management of active thyroid eye disease

Thyroid eye disease (TED) is an autoimmune inflammatory disease of the orbit and the most common extrathyroidal manifestation of Graves disease. The release of pro-inflammatory cytokines is associated with inflammation of the ocular surface and lacrimal gland along with periorbital skin erythema and edema. Resultant tissue remodeling, fibrosis, and fat deposition can impart permanent physical changes to the ocular adnexa with effects on function and cosmesis. These changes occur in the active phase of disease, and it is during this time that steroids are often relied on to help alleviate symptoms. Due to the common and predictable side effects of long-term and high-dose steroid use, there has been a continuous effort to find alternative steroid-sparing medical management options for TED. This review highlights the various research studies that support the use of these medications.

Cytokine and chemokine profile changes in patients after intravitreal conbercept injection for center macular edema due to branch retinal vein occlusion

PURPOSE

This study aimed to ascertain cytokine concentrations in patients with center macular edema (CME) due to branch retinal vein occlusion (BRVO) before and during the period of treatment with intravitreal injection of conbercept (IVC) and to determine the relationship between these concentrations and disease activity.

MATERIALS AND METHODS

The Bio-Plex^® 200 System and the Bio-Plex^TM Human Cytokine Standard 27-Plex, Group I (Bio-Rad, Hercules, California, USA) were used to detect cytokine concentrations in aqueous humour. Experimental aqueous humour samples were collected from 22 patients with CME due to BRVO when IVC was administered at baseline and at 1 month, and control aqueous samples were collected by limbal paracentesis from 16 patients undergoing routine cataract surgery.

RESULTS

Significantly higher concentrations of vascular endothelial growth factor (VEGF), interleukin 6 (IL-6), IL-8, interferon gamma-induced protein 10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) were found in the BRVO group than in the control group. In the BRVO group, VEGF levels were significantly lower one month after IVC than at baseline. However, the other cytokines did not significantly change during IVC treatment. The decreases in VEGF levels were closely related to the decreases in central macular thickness (CMT) and the increases in best-corrected visual acuity (BCVA).

CONCLUSIONS

Many factors, such as angiogenic, inflammatory and growth factors, contribute to the pathogenesis of CME due to BRVO. IVC had no significant effect on cytokines other than VEGF in patients with CME due to BRVO. The changes in BCVA and CMT were associated with VEGF levels after IVC treatment.

Recent Trends in Electrochemical Sensors for Vital Biomedical Markers Using Hybrid Nanostructured Materials

This work provides a succinct insight into the recent developments in electrochemical quantification of vital biomedical markers using hybrid metallic composite nanostructures. After a brief introduction to the biomarkers, five types of crucial biomarkers, which require timely and periodical monitoring, are shortlisted, namely, cancer, cardiac, inflammatory, diabetic and renal biomarkers. This review emphasizes the usage and advantages of hybrid nanostructured materials as the recognition matrices toward the detection of vital biomarkers. Different transduction methods (fluorescence, electrophoresis, chemiluminescence, electrochemiluminescence, surface plasmon resonance, surface-enhanced Raman spectroscopy) reported for the biomarkers are discussed comprehensively to present an overview of the current research works. Recent advancements in the electrochemical (amperometric, voltammetric, and impedimetric) sensor systems constructed with metal nanoparticle-derived hybrid composite nanostructures toward the selective detection of chosen vital biomarkers are specifically analyzed. It describes the challenges involved and the strategies reported for the development of selective, sensitive, and disposable electrochemical biosensors with the details of fabrication, functionalization, and applications of hybrid metallic composite nanostructures.

Immune Th17 lymphocytes play a critical role in the multiple beneficial properties of resveratrol

Modulation of the inflammatory response is one of the major issues of the 21st century due to its importance in the occurrence of various pathologies (cancer, autoimmune diseases, degenerative diseases) and their progression over time. Whether acute or chronic, the inflammatory response is directly related to the immune response through different subtypes of T lymphocytes. In addition, among the compounds capable of modulating the cells of the immune system, resveratrol, a polyphenol with pleiotropic biological properties, seems to be a good candidate. Indeed, resveratrol is able to alter the immune response by modulating the process of lymphocyte differentiation and subsequently diminishing the inflammatory-associated response. More specifically, thanks to its ability to act as a sirtuin-1 agonist, it can deacetylate the transcription factor STAT3 and alter nuclear factors essential to the process of lymphocyte differentiation. We present and discuss these different aspects in relation to various pathologies and how the alteration of the ratios between the different lymphocyte subtypes by resveratrol is an important element to take into account when studying its anti-inflammatory and immunomodulatory properties.

Aqueous Humor Mediator and Cytokine Aberrations in Diabetic Retinopathy and Diabetic Macular Edema: A Systematic Review and Meta-Analysis

Purpose

To evaluate the relationship between the aqueous humor levels of VEGF, TNF-α, IL-10, IL-6, IL-12, MCP-1, and IP-10 with DR/DME.

Methods

PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched up to October 2018. Systematic review and meta-analysis were conducted.

Results

18 studies comprising 362 cases with DR (100 with DME) and 620 controls without DR were included in this meta-analysis. There was a significant association between VEGF levels in the aqueous humor and DR (standardized mean difference (SMD) 1.94 (95% CI 1.05-2.83)) and DME (1.07 (0.71, 1.42)). Furthermore, a significant correlation was observed between levels of IL-6 and DR (3.53 (0.37, 6.69)), and similarly correlation with DME (1.26 (0.30, 2.21)). The relationship between MCP-1 and DR and DME was significant, in which the SMD was (0.49 (0.09, 0.89)) and (1.49 (0.78, 2.20)), respectively. However, IL-12, IP-10, and TNF-α had no correlation with DR and DME, whereas there was a significant relationship between IL-8 and DME (1.68 (0.97, 2.40)).

Conclusion

Elevated levels of VEGF, IL-6, and MCP-1 in the aqueous humor were associated with the risk for the presence of DR, and levels of VEGF, IL-6, IL-8, and MCP-1 were associated with the risk of DME. Furthermore, these biomarkers may be used as potential predictors or therapeutic targets for DR/DME.

Modelling Macular Edema: The Effect of IL-6 and IL-6R Blockade on Human Blood-Retinal Barrier Integrity In Vitro

Purpose

Macular edema (ME) is a leading cause of visual loss in a range of retinal diseases and despite the use of antivascular endothelial growth factor (anti-VEGF) agents, its successful treatment remains a major clinical challenge. Based on the indirect clinical evidence that interleukin-6 (IL-6) is a key additional candidate mediator of ME, we interrogated the effect of IL-6 on blood–retinal barrier (BRB) integrity in vitro.

Methods

Human retinal pigment epithelial cell (ARPE-19) and human retinal microvascular endothelial cell (HRMEC) monolayers were used to mimic the outer and inner BRB, respectively. Their paracellular permeability was assessed by measuring the passive permeation of 40 kDa fluorescein isothiocyanate (FITC)-dextran across confluent cells in the presence of IL-6. Transendothelial/epithelial electrical resistance (TEER) then was measured and the distribution of the tight junction protein ZO-1 was assessed by immunofluorescence using confocal microscopy.

Results

Treatment with IL-6 for 48 hours significantly increased the diffusion rate of FITC-dextran, decreased TEER, and disrupted the distribution of ZO-1 in ARPE-19 cells, which constitutively express the IL-6 transmembrane receptor, and this was reversed with IL-6R blockade. In contrast, IL-6 did not affect the paracellular permeability, TEER, or ZO-1 distribution in HRMECs.

Conclusions

These in vitro data support the hypothesis that IL-6 reversibly disrupts the integrity of ARPE-19 cells, but it does not affect HRMECs.

Translational Relevance

IL-6 is a candidate therapeutic target in the treatment of outer BRB driven ME.

Interleukin-6 inhibition in the management of non-infectious uveitis and beyond

Background

Uveitis consists of a spectrum of inflammatory disorders characterized by ocular inflammation. The underlying pathophysiology consists of a complex interplay of various inflammatory pathways. Interleukin 6 is an important mediator of inflammation in uveitis and constitutes focus of research toward development of newer biological therapies in the management of non-infectious uveitis.

Main body

Pan-blockade of the inflammatory pathways with steroids is generally the first step in the management of acute non-infectious uveitis. However, long-term therapy with steroids is associated with systemic and ocular side effects, thereby necessitating the need for development of steroid sparing agents. IL-6 is a cytokine produced by various immune cells, in response to molecular patterns and affects multiple inflammatory cells. In particular, IL-6 is involved in differentiation of CD-4 cells into Th-17 cells that have been shown to play a significant role in various immune-mediated diseases such as uveitis. This broad-spectrum immunomodulatory activity makes IL-6 an excellent target for immunomodulatory therapy. Tocilizumab was the first IL-6 inhibitor to demonstrate efficacy in humans. It inhibits IL-6 from binding to both membrane-bound and soluble receptor and can be administered via intravenous (IV) and subcutaneous (SC) routes. It has been FDA approved for treatment of rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). Following the approval in systemic diseases, its efficacy was demonstrated in various uveitis studies including a phase 2 clinical trial (STOP-Uveitis). Overall, tocilizumab has shown a good safety profile with the risk of malignancy consistent with that expected in patients with rheumatoid arthritis. However, tocilizumab therapy has been shown to increase the risk for gastrointestinal perforation and dose-dependent neutropenia. Following the success of tocilizumab, several other agents targeting the IL-6 pathway are in the pipeline. These include sirukumab, siltuximab, olokizumab, clazakizumab, and EBI-031 which target IL-6; Sarilumab and ALX-0061 act on the IL-6 receptor.

Conclusion

Studies have shown that IL-6 inhibitors can be effective in the management of NIU. In addition, the levels of IL-6 are elevated in other ocular vascular diseases such as retinal vein occlusion and diabetic macular edema. The roles of IL-6 inhibition may be broadened in the future to include the management of retinal vascular diseases and non-uveitic macular edema.

Targeting innate immune mediators in type 1 and type 2 diabetes

Type 1 and type 2 diabetes are characterized by chronic inflammation; both diseases involve pancreatic islet inflammation, while systemic low-grade inflammation is a feature of obesity and type 2 diabetes. Long-term activation of the innate immune system impairs insulin secretion and action, and inflammation also contributes to macrovascular and microvascular complications of diabetes. However, despite strong preclinical evidence and proof-of-principle clinical trials demonstrating that targeting inflammatory pathways can prevent cardiovascular disease and other complications in patients with diabetes, there are still no approved treatments for diabetes that target innate immune mediators. Here, we review recent advances in our understanding of the inflammatory pathogenesis of type 1 and type 2 diabetes from a translational angle and point out the critical gaps in knowledge that need to be addressed to guide drug development.

Inflammation in the Pathophysiology and Therapy of Cardiometabolic Disease

The role of chronic inflammation in the pathogenesis of type 2 diabetes mellitus and associated complications is now well established. Therapeutic interventions counteracting metabolic inflammation improve insulin secretion and action and glucose control and may prevent long-term complications. Thus, a number of anti-inflammatory drugs approved for the treatment of other inflammatory conditions are evaluated in patients with metabolic syndrome. Most advanced are clinical studies with IL-1 antagonists showing improved β-cell function and glycemia and prevention of cardiovascular diseases and heart failure. However, alternative anti-inflammatory treatments, alone or in combinations, may turn out to be more effective, depending on genetic predispositions, duration, and manifestation of the disease. Thus, there is a great need for comprehensive and well-designed clinical studies to implement anti-inflammatory drugs in the treatment of patients with metabolic syndrome and its associated conditions.

New onset or exacerbation of uveitis with infliximab: paradoxical effects?

Objective

To report four cases of new onset or exacerbation of uveitis following administration of infliximab.

Methods

This retrospective observational case series includes four patients who developed new onset or exacerbation of uveitis paradoxically during infliximab treatment.

Results

Four patients were assessed, including three women, with a mean age of 33 (14–84) years. Infliximab was introduced for the treatment of scleritis associated with rheumatoid arthritis (two cases), chronic anterior uveitis associated with juvenile idiopathic arthritis (JIA) (one case) and Crohn’s disease (one case). Anterior scleritis associated with rheumatoid arthritis successfully improved following infliximab administration; however, macular oedema or dense vitritis paradoxically developed in two cases. In one case, infliximab was switched to tocilizumab. In another case, infliximab was discontinued, and additional corticosteroids and immunosuppressive medications were added. In one patient with JIA, new-onset macular oedema and exacerbation of anterior uveitis were observed during infliximab treatment, so the patient was switched to adalimumab. In the patient with Crohn’s disease treated with infliximab, severe vasculitis and macular oedema occurred, requiring intravitreal triamcinolone injection. The patient was switched to adalimumab. Given that these reactions were paradoxical effects of infliximab, infliximab treatment was discontinued in all cases, and additional corticosteroids or immunosuppressive medications were added. All cases remained free of ocular inflammation at the last visit.

Conclusion

Uveitis rarely occurs de novo or is exacerbated during infliximab treatment. Cessation of infliximab led to resolution of this paradoxical adverse effect.

The role of inflammation in diabetic eye disease

Mounting evidence suggests that immunological mechanisms play a fundamental role in the pathogenesis of diabetic retinopathy (DR) and diabetic macular edema (DME). Upregulation of cytokines and other proinflammatory mediators leading to persistent low-grade inflammation is believed to actively contribute to the DR-associated damage to the retinal vasculature, inducing breakdown of the blood-retinal barrier, subsequent macular edema formation, and promotion of retinal neovascularization. This review summarizes the current knowledge of the biological processes providing an inflammatory basis for DR and DME. In addition, emerging therapeutic approaches targeting inflammation are discussed, including blockade of angiopoietin 2 and other molecular targets such as interleukin (IL)-6, IL-1β, plasma kallikrein, and integrins.

MicroRNAs in the cornea: Role and implications for treatment of corneal neovascularization

With no safe and efficient approved therapy available for treating corneal neovascularization, the search for alternative and effective treatments is of great importance. Since the discovery of miRNAs as key regulators of gene expression, knowledge of their function in the eye has expanded continuously, facilitated by high throughput genomic tools such as microarrays and RNA sequencing. Recently, reports have emerged implicating miRNAs in pathological and developmental angiogenesis. This has led to the idea of targeting these regulatory molecules as a therapeutic approach for treating corneal neovascularization. With the growing volume of data generated from high throughput tools applied to study corneal neovascularization, we provide here a focused review of the known miRNAs related to corneal neovascularization, while presenting new experimental data and insights for future research and therapy development.

Anti-IL6-Receptor Tocilizumab in Refractory and Noninfectious Uveitic Cystoid Macular Edema: Multicenter Study of 25 Patients

PURPOSE

Cystoid macular edema (CME) is a leading cause of blindness. This study assessed the efficacy and safety of tocilizumab (TCZ) in refractory CME.

DESIGN

Retrospective case series.

METHODS

Patients with CME secondary to noninfectious uveitis who had inadequate response to corticosteroids and at least 1 conventional immunosuppressive drug, and in most cases to other biological agents, were studied. CME was defined as central retinal thickness greater than 300 μm. The primary outcome measure was macular thickness. Intraocular inflammation, best-corrected visual acuity (BCVA), and corticosteroid-sparing effect were also analyzed.

RESULTS

A total of 25 patients (mean ± standard deviation age 33.6 ± 18.9 years; 17 women) with CME were assessed. Underlying diseases associated with uveitis-related CME are juvenile idiopathic arthritis (n = 9), Behçet disease (n = 7), birdshot retinochoroidopathy (n = 4), idiopathic (n = 4), and sarcoidosis (n = 1). The ocular patterns were panuveitis (n = 9), anterior uveitis (n = 7), posterior uveitis (n = 5), and intermediate uveitis (n = 4). Most patients had CME in both eyes (n = 24). TCZ was used in monotherapy (n = 11) or combined with conventional immunosuppressive drugs. Regardless of the underlying disease, compared to baseline, a statistically significant improvement in macular thickness (415.7 ± 177.2 vs 259.1 ± 499.5 μm; P = .00009) and BCVA (0.39 ± 0.31 vs 0.54 ± 0.33; P = .0002) was obtained, allowing us to reduce the daily dose of prednisone (15.9 ± 13.6 mg/day vs 3.1 ± 2.3 mg/day; P = .002) after 12 months of therapy. Remission was achieved in 14 patients. Only minor side effects were observed after a mean follow-up of 12.7 ± 8.34 months.

CONCLUSION

Macular thickness is reduced following administration of TCZ in refractory uveitis-related CME.

Green tea catechins alleviate autoimmune symptoms and visual impairment in a murine model for human chronic intraocular inflammation by inhibiting Th17-associated pro-inflammatory gene expression

Autoimmune uveitis is a sight-threatening disease mainly caused by dysregulation of immunity. We investigated the therapeutic effects of green tea extract (GTE) and its major component, epigallocatechin-3-gallate (EGCG), on a murine model of experimental autoimmune uveoretinitis (EAU). Oral administration of GTE, EGCG, dexamethasone, or water, which started 5 days before the induction, was fed every two days to each group. On day 21 post induction, the eyes were examined by confocal scanning laser ophthalmoscopy, optical coherence tomography (OCT), fundus fluorescein angiography (FFA) and electroretinography (ERG) prior to sacrificing the animals for histological assessments and gene expression studies. Retinal-choroidal thicknesses (RCT) and major retinal vessel diameter were measured on OCT sections and FFA images, respectively. Comparing to water-treated EAU animals, GTE attenuated uveitis clinical manifestations, RCT increase (1.100 ± 0.013 times vs 1.005 ± 0.012 times, P < 0.001), retinal vessel dilation (308.9 ± 6.189 units vs 240.8 units, P < 0.001), ERG amplitudes attenuation, histopathological ocular damages, and splenomegaly in EAU mice. The therapeutic effects of GTE were dose dependent and were comparable to dexamethasone. EGCG, a major active constituent of GTE, partially alleviated uveitic phenotypes including recovering visual function. Th-17 associated pro-inflammatory gene [interleukin 1 beta (IL-1β), IL-6, IL-17A, and tumor necrosis factor alpha (TNF-α)] expressions were down regulated by GTE and EGCG treatments, which showed no detectable morphological defects in liver and kidney in non-induced and EAU mice. Our findings suggest that GTE consumption can serve as a potent therapeutic agent as well as a food supplement for developing alternative treatments against autoimmune uveitis.

Platelet-rich plasma as a site-targeted approach in wound healing: a molecular perspective

Wound healing remained an equation with multiple variables that experts in the medical field are trying to solve. The need to find an adjuvant that can quicken the healing process is increasing with every day, as longer wound healing times raise the risk of infections. Platelet-rich plasma is a promising tool promoting faster healing in a variety of wounds (thermal wounds, burn wounds, surgeries, etc.), as a series of studies present encouraging results in patients that received platelet-rich plasma treatment. The aim of this paper is to review and comment on the useful benefits and limitations of using platelet-rich plasma as an adjuvant strategy in wound healing, emphasizing on skin related wounds.