Influence of corticosteroid therapy on IL-18 and nitric oxide production during Behçet's disease

Promotion of 14-3-3ζ/Heme Oxygenase-1 Axis on Endotoxin-Induced Uveitis and Microglia Ferroptosis in Mice

PURPOSE

Uveitis is a common, sight-threatening inflammatory ocular disease and is the main cause of blindness, which is caused by autoimmune response, infection, and injury. The contribution of 14-3-3ζ in uveitis remains obscure. This study aims to investigate the role of 14-3-3ζ in regulating ferroptosis in retinal inflammation and its contribution to uveitis.

METHODS

A lipopolysaccharide (LPS)-induced uveitis mouse model and BV-2 cell line were used to examine the effect of LPS stimulation on the expression of 14-3-3ζ and ferroptosis in microglia. The expression of heme oxygenase-1 (HO-1) was also analyzed to understand its role in promoting microglial ferroptosis.

RESULTS

We found that LPS stimulation increased the expression of 14-3-3ζ and promoted ferroptosis in microglia. Additionally, 14-3-3ζ was found to promote microglial ferroptosis by stabilizing the expression of HO-1. These findings suggest that the 14-3-3ζ/HO-1 axis plays a crucial role in promoting microglial ferroptosis in retinal inflammation.

CONCLUSION

The study provides valuable insights into the mechanisms underlying uveitis and highlights the potential of the 14-3-3ζ/HO-1 axis as a therapeutic target for the disease. Further research in this area could lead to the development of preventive and therapeutic strategies for uveitis.

[The CD40-CD40L axis: Current and future implications in clinical immunology]

The CD40-CD40 ligand (CD40L) pathway is a backbone of communication between cells of the immune system. It makes it possible to generate a proinflammatory signal and thus participates in the pathogenesis of dysimmune diseases, transplant rejection and atherosclerosis. Because of this therapeutic target of choice, several generations of anti-CD40L monoclonal antibodies have emerged since the 1990s. The first generation of antibodies was responsible for thromboembolic toxicity for which the mechanisms are starting to be defined. New generations of antibodies were designed to overcome this toxicity and are still being developed in lupus, rheumatoid arthritis, Sjogren's syndrome or immunologic thrombocytopenia. In addition to these targeted therapies, there are data suggesting the impact of several drugs among molecules used in cardiology and clinical immunology on the level of CD40L. The objective of this review is to recall the clinical issues related to the CD40-CD40L axis and to present current or future treatments that block CD40L which would allow clinicians to diversify their options for managing dysimmune diseases.

Comprehensive analysis of immunoglobulin and clinical variables identifies functional linkages and diagnostic indicators associated with Behcet's disease patients receiving immunomodulatory treatment

BACKGROUND

Behcet's disease (BD) is a relapsing systemic vascular autoimmune/inflammatory disease. Despite much effort to investigate BD, there are virtually no unique laboratory markers identified to help in the diagnosis of BD, and the pathogenesis is largely unknown. The aim of this work is to explore interactions between different clinical variables by correlation analysis to determine associations between the functional linkages of different paired variables and potential diagnostic biomarkers of BD.

METHODS

We measured the immunoglobulin proteome (IgG, IgG1-4, IgA, IgA1-2) and 29 clinical variables in 66 healthy controls and 63 patients with BD. We performed a comprehensive clinical variable linkage analysis and defined the physiological, pathological and pharmacological linkages based on the correlations of all variables in healthy controls and BD patients without and with immunomodulatory therapy. We further calculated relative changes between variables derived from comprehensive linkage analysis for better indications in the clinic. The potential indicators were validated in a validation set with 76 patients with BD, 30 healthy controls, 18 patients with Takayasu arteritis and 18 patients with ANCA-associated vasculitis.

RESULTS

In this study, the variables identified were found to act in synergy rather than alone in BD patients under physiological, pathological and pharmacological conditions. Immunity and inflammation can be suppressed by corticosteroids and immunosuppressants, and integrative analysis of granulocytes, platelets and related variables is likely to provide a more comprehensive understanding of disease activity, thrombotic potential and ultimately potential tissue damage. We determined that total protein/mean corpuscular hemoglobin and total protein/mean corpuscular hemoglobin levels, total protein/mean corpuscular volume, and plateletcrit/monocyte counts were significantly increased in BD compared with controls (P < 0.05, in both the discovery and validation sets), which helped in distinguishing BD patients from healthy and vasculitis controls. Chronic anemia in BD combined with increased total protein contributed to higher levels of these biomarkers, and the interactions between platelets and monocytes may be linked to vascular involvement.

CONCLUSIONS

All these results demonstrate the utility of our approach in elucidating the pathogenesis and in identifying novel biomarkers for autoimmune diseases in the future.

Effect of combined colchicine-corticosteroid treatment on neutrophil/lymphocyte ratio: a predictive marker in Behçet disease activity

BACKGROUND AND AIMS

Behçet's disease (BD) is an auto-immune vasculitis, characterized by episodic inflammation of multiple organs. The neutrophil to lymphocyte ratio (NLR) is used as a marker of inflammation in several diseases nowadays. While nitric oxide (NO) seem to be involved in BD pathogenicity. Our study aims to investigate the NLR as an inflammatory marker of BD activity as well as to evaluate the relationship between the NO production and NLR in Algerian BD patients with different clinical manifestations before and under colchicine + corticosteroid treatment.

METHODS

For this purpose, we evaluated the NLR as the ratio of neutrophil count to lymphocyte count in naïve and treated active BD patients with different clinical manifestations and in inactive ones. Furthermore, we assessed NO production by the Griess' method in the same patients. Additionally, we evaluated in vivo interferon-γ (IFN-γ) and interleukin-4 (IL-4) levels using ELISA.

RESULTS AND DISCUSSION

Our results indicate that the NLR and nitrite levels were higher in naïve active BD patients. Interestingly, this high ratio and NO production differed according to the clinical manifestations and was associated with an increased risk of mucocutaneous and vascular involvement. Importantly, in treated BD patients NLR was higher in active patients especially in those with mucocutaneous involvement while increased nitrites levels were regardless of the clinical manifestations studied. Both NLR and NO production decreased in these treated active patients. In addition, IL-4 production differed according to the clinical manifestations studied contrary to the IFN-γ production.

CONCLUSION

Collectively our results suggest that the NLR is a potential marker of BD activity in Algerian patients, predicting the disease severity. Moreover, the positive relationship between the NLR and NO production is related to an increased risk of mucocutaneous lesions and vascular involvement. Thus, the application of these two accessible tools could be benefit for the clinical prognosis and treatment of BD.

Uric acid increases IL-1β secretion and Caspase-1 activation in PBMCs of Behçet's disease patients: The in vitro immunomodulatory effect of xanthine oxidase inhibitor Allopurinol

Behçet's disease (BD) is a multisystem disease, which shares some features with other diseases belonging to the autoinflammatory disorders panel. Recent studies have postulated that IL-1β/Caspase-1 may play a cardinal role in autoinflammatory diseases. In this study, we aimed to (i) elucidate the mechanism underlying the involvement of xanthine oxidase (XO) and Uric Acid (UA) in BD (ii) study the direct effects of UA and XO inhibitor "Allopurinol" on nitric oxide (NO) and caspase-1-mediated IL-1β release in peripheral blood mononuclear cells (PBMCs) of BD patients. In this context, plasma of BD patients and healthy controls (HC) were used to measure XO activity, UA, advanced oxidized proteins products (AOPP) and NO levels. In Addition, PBMCs of BD patients and HC were treated or not with either UA or Allopurinol. Then we quantified NO and IL-1β levels, and Caspase-1 Activity in the supernatants and lysates of PBMCs, respectively. We showed that plasma levels of XO activity, UA, AOPP and NO are significantly increased in BD patients compared to those of HC. Interestingly, a significant positive correlation between XO and UA was observed in BD patients. Additionally, while UA has markedly increased NO, IL-1β, and Caspase-1 activity levels in PBMCs of BD patients, Allopurinol has exerted an immunomodulatory effect resulting in reduced NO, IL-1β and Caspase-1 levels in PBMCs of BD patients particularly during the active stages. Collectively, our results indicate a potential clinical use of XO as a tool for assessing BD activity, and suggest that the in-vitro immunomodulatory effect of Allopurinol may have a promising therapeutic value in BD management.