Targeting cytokines to treat autoinflammatory diseases

A narrative review on the role of cytokines in the pathogenesis and treatment of familial Mediterranean fever: an emphasis on pediatric cases

Familial Mediterranean Fever (FMF) is a hereditary autoinflammatory disease characterized by an early onset of recurrent fever and serositis episodes. FMF is caused by mutations in the MEFV gene which encodes the pyrin protein, an IL-1β mediated inflammation regulator. Recent findings have identified a plethora of molecules and pathways involved in the regulation of inflammation and innate immunity, hence increasing our understanding of the etiology and inflammatory nature of FMF. Cytokines, in particular, have been found to play a key role in the pathogenesis and treatment of the disease. Indeed, various studies associated cytokines' genetic variations and expression with susceptibility to and severity of the disease, which was further supported by the positive response of patients, both children and adults, to targeted cytokine blocking therapies. These studies highlighted the potential use of cytokines as biomarkers and target in resistant/intolerant patients and contributed to improving the early detection of FMF in children, thus enhancing their quality of life and providing alternative treatment for severe cases. The aim of this review is to provide the latest updates on the pivotal role of cytokines in FMF and to discuss the efficacy and safety of anti-cytokine biologics by primarily focusing on pediatric FMF cases.

Paradoxical Psoriasis in Patients Receiving Therapy with Tumor Necrosis Factor Inhibitors: Potential Pathogenic Mechanisms and the Role of Genetic Factors

TNF inhibitors (TNFi) have revolutionized the therapeutic management of various chronic immune-mediated inflammatory diseases. Despite their known benefits, these therapies are related to paradoxical adverse effects (PAEs), including paradoxical psoriasis (PP). Although the underlying mechanism remains somewhat unclear, some theories suggest that genetic factors, particularly certain single-nucleotide polymorphisms (SNPs), may play an important role. The present review aimed to research and analyze recent findings regarding the pathomechanisms involved in the appearance of PP and the association between various genetic factors and PP in individuals treated with TNFi. We performed a literature search and found that certain genes (IL23R, TNF, FBXL19, CTLA4, SLC12A8, TAP1) are strongly associated with the occurrence of PP in pediatric and adult patients during therapy with TNFi. The identification of the specific SNPs involved in the appearance of PP and other PAEs in patients treated with TNFi for various diseases and in different populations may later favor the recognition of those patients at a high risk of developing such adverse effects and could guide personalized therapeutic strategies in future years.

Genetic variations of IL10 and IL6R genes in acute anterior uveitis in Han Chinese

BACKGROUND

Several autoimmune disorders have been linked to polymorphisms in IL10 and IL6R genes. This research aimed to study whether single nucleotide polymorphisms (SNPs) in the genes of IL10 and IL6R were associated with acute anterior uveitis (AAU) in Han Chinese.

METHODS

Genotyping was carried out by the iPLEX Gold Genotyping Assay. Our study comprised 420 patients with AAU and 918 healthy subjects from Han Chinese. Using the chi-square (χ2) test, alleles and genotypes were analyzed between AAU subjects and healthy controls.

RESULTS

All ten SNPs were successfully genotyped and four SNPs (IL10/rs1800871, IL10/rs3021094, IL10/rs2222202, IL6R/rs4845618) exhibited weak associations with AAU, as indicated by their Puncorr values. However, upon applying the Bonferroni correction, there was no significant association between AAU and the control subjects. Additionally, the haplotype analysis of the ten SNPs revealed no association with AAU.

CONCLUSION

Our findings suggested that polymorphisms of the tested ten SNPs on the IL10 and IL6R genes did not show any association with the risk of developing AAU among the Han Chinese population.

Interleukin inhibitors and the associated risk of candidiasis

Interleukins (ILs) are vital in regulating the immune system, enabling to combat fungal diseases like candidiasis effectively. Their inhibition may cause enhanced susceptibility to infection. IL inhibitors have been employed to control autoimmune diseases and inhibitors of IL-17 and IL-23, for example, have been associated with an elevated risk of Candida infection. Thus, applying IL inhibitors might impact an individual's susceptibility to Candida infections. Variations in the severity of Candida infections have been observed between individuals with different IL inhibitors, necessitating careful consideration of their specific risk profiles. IL-1 inhibitors (anakinra, canakinumab, and rilonacept), IL-2 inhibitors (daclizumab, and basiliximab), and IL-4 inhibitors (dupilumab) have rarely been associated with Candida infection. In contrast, tocilizumab, an inhibitor of IL-6, has demonstrated an elevated risk in the context of coronavirus disease 2019 (COVID-19) treatment, as evidenced by a 6.9% prevalence of candidemia among patients using the drug. Furthermore, the incidence of Candida infections appeared to be higher in patients exposed to IL-17 inhibitors than in those exposed to IL-23 inhibitors. Therefore, healthcare practitioners must maintain awareness of the risk of candidiasis associated with using of IL inhibitors before prescribing them. Future prospective studies need to exhaustively investigate candidiasis and its associated risk factors in patients receiving IL inhibitors. Implementing enduring surveillance methods is crucial to ensure IL inhibitors safe and efficient utilization of in clinical settings.

Inflammasome-triggered IL-18 controls skin inflammation in the progression of Buruli ulcer

Buruli ulcer is an emerging chronic infectious skin disease caused by Mycobacterium ulcerans. Mycolactone, an exotoxin produced by the bacterium, is the only identified virulence factor so far, but the functions of this toxin and the mechanisms of disease progression remain unclear. By interfering Sec61 translocon, mycolactone inhibits the Sec61-dependent co-translational translocation of newly synthesized proteins, such as induced cytokines and immune cell receptors, into the endoplasmic reticulum. However, in regard to IL-1β, which is secreted by a Sec61-independent mechanism, mycolactone has been shown to induce IL-1β secretion via activation of inflammasomes. In this study, we clarified that cytokine induction, including that of IL-1β, in infected macrophages was suppressed by mycolactone produced by M. ulcerans subsp. shinshuense, despite the activation of caspase-1 through the inflammasome activation triggered in a manner independent of mycolactone. Intriguingly, mycolactone suppressed the expression of proIL-1β as well as TNF-α at the transcriptional level, suggesting that mycolactone of M. ulcerans subsp. shinshuense may exert additional inhibitory effect on proIL-1β expression. Remarkably, constitutively produced IL-18 was cleaved and mature IL-18 was actually released from macrophages infected with the causative mycobacterium. IL-18-deficient mice infected subcutaneously with M. ulcerans exhibited exacerbated skin inflammation during the course of disease progression. On the other hand, IL-1β controls bacterial multiplication in skin tissues. These results provide information regarding the mechanisms and functions of the induced cytokines in the pathology of Buruli ulcer.

Can vitamin D be an adjuvant therapy for juvenile rheumatic diseases?

Vitamin D, known for its essential role in calcium and bone homeostasis, has multiple effects beyond the skeleton, including regulation of immunity and modulation of autoimmune processes. Several reports have shown suboptimal serum 25 hydroxyvitamin D [25(OH)D] levels in people with different inflammatory and autoimmune rheumatic conditions, and an association between 25(OH)D levels, disease activity and outcomes. Although most available data pertain to adults, insights often are extended to children. Juvenile rheumatic diseases (JRDs) are a significant health problem during growth because of their complex pathogenesis, chronic nature, multisystemic involvement, and long-term consequences. So far, there is no definitive or clear evidence to confirm the preventive or therapeutic effect of vitamin D supplementation in JRDs, because results from randomized controlled trials (RCTs) have produced inconsistent outcomes. This review aims to explore and discuss the potential role of vitamin D in treating selected JRDs. Medline/PubMed, EMBASE, and Scopus were comprehensively searched in June 2023 for any study on vitamin D supplementary role in treating the most common JRDs. We used the following keywords: "vitamin D" combined with the terms "juvenile idiopathic arthritis", "juvenile systemic scleroderma", "juvenile systemic lupus erythematosus", "juvenile inflammatory myopathies", "Behcet disease", "periodic fever syndromes" and "juvenile rheumatic diseases". Observational studies have found that serum 25(OH)D concentrations are lower in juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, juvenile systemic scleroderma, Behcet disease and proinflammatory cytokine concentrations are higher. This suggests that vitamin D supplementation might be beneficial, however, current data are insufficient to confirm definitively the complementary role of vitamin D in the treatment of JRDs. Considering the high prevalence of vitamin D deficiency worldwide, children and adolescents should be encouraged to supplement vitamin D according to current recommendations. More interventional studies, especially well-designed RCTs, assessing the dose-response effect and adjuvant effect in specific diseases, are needed to determine the potential significance of vitamin D in JRDs treatment.

Autoinflammatory Recurrent Pericarditis Associated with a New NLRP12 Mutation in a Male Adolescent

Idiopathic recurrent pericarditis (IRP) can be the hallmark of an autoinflammatory syndrome with recurrent attacks of chest pain and symptom-free intervals following an acute episode. The recurrence rate may be 35% in the pediatric population, frequently with less severe manifestations than at the first episode. Pericarditis can be the sole clinical manifestation or may be part of a systemic autoinflammatory disease (SAID), especially in the case of a recurrence. Familial Mediterranean Fever (FMF), Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS), Mevalonate-Kinase Deficiency (MKD), nucleotide-binding oligomerization domain 2 (NOD2)-associated autoinflammatory syndrome, and others are closely related to IRP based on similar clinical manifestations and treatment responses to anti-interleukin 1 (IL-1) agents, such as anakinra, and should therefore be excluded in patients with IRP. A newly described SAID, an autosomal dominant disorder known as NLRP12-AID (nucleotide-binding leucine-rich repeat-containing receptor 12-related autoinflammatory disease) is caused by heterozygous mutations in the NLRP12 gene and most commonly affects children. Fewer than 40 pediatric patients with NLRP12-AID have been described in the medical literature, with none presenting with RP. We report a case of relapsing pericarditis responsive to anti-IL-1 therapy in a male adolescent who carried a missense mutation in the NLRP12 gene potentially causative of the excessive activation of inflammatory pathways. This is a unique case in the medical literature that associates recurrent pericarditis in an adolescent presumed to be related to the missense mutation in the NLRP12 gene. The role of the NLRP12 inflammasome in generating and maintaining recurrent pericardial inflammation should be considered.

Systemic autoinflammatory disorders

Inflammation is a physiologic defense mechanism against an out-side attack. Usually, it resolves after the removal of noxious causes, but systemic autoinflammatory disorders (SAIDs) have recurrent or repeated acute inflammation through uncontrolled gene function, which can present as gain-of-function or loss-of-function of a gene during inflammation. Most SAIDs are hereditary autoinflammatory diseases and develop by dysregulation of innate immunity through various pathways including inflammasomes, endoplasmic reticulum stress, nuclear factor-κB dysregulation, and interferon production. The clinical manifestations include periodic fever with various skin findings such as neutrophilic urticarial dermatosis, or vasculitic lesions. Some SAID cases stem from immunodeficiency or allergic reactions related to monogenic mutation. The diagnosis of SAIDs is based on clinical findings of systemic inflammation and genetic confirmation, and have to exclude infections or malignancies. Moreover, a genetic study is essential for clinical features to be suspect SAID with or without a family history. Treatment is based on understanding the immunopathology of SAID, and targeted therapy to control disease flares, reduce recurrent acute phases and prevent serious complications. Diagnosing and treating SAID requires understanding its comprehensive clinical features and pathogenesis related to genetic mutation.

Identification of novel clusters of co-expressing cytokines in a diagnostic cytokine multiplex test

Introduction

Cytokines are mediators of the immune system that are essential for the maintenance, development and resolution of immune responses. Beneficial immune responses depend on complex, interdependent networks of signaling and regulatory events in which individual cytokines influence the production and release of others. Since disruptions in these signaling networks are associated with a wide spectrum of diseases, cytokines have gained considerable interest as diagnostic, prognostic and precision therapy-relevant biomarkers. However, currently individual cytokines testing has limited value because the wider immune response context is often overlooked. The aim of this study was to identify specific cytokine signaling patterns associated with different diseases.

Methods

Unbiased clustering analyses were performed on a clinical cytokine multiplex test using a cohort of human plasma specimens drawn from individuals with known or suspected diseases for which cytokine profiling was considered clinically indicated by the attending physician.

Results and discussion

Seven clusters of co-expressing cytokines were identified, representing common patterns of immune activation. Common expression profiles of the cytokine clusters and preliminary associations of these profiles with specific diseases or disease categories were also identified. These findings increase our understanding of the immune environments underlying the clinical presentations of patients of inflammatory, autoimmune and neoplastic diseases, which could then improve diagnoses and the identification of evidence-based treatment targets.

An integrated cytokine and kynurenine network as the basis of neuroimmune communication

Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.

Immune-mediated inflammatory diseases with chronic excess of serum interleukin-18

Review: Interleukin-18 (IL-18) is a proinflammatory cytokine that promotes various innate immune processes related to infection, inflammation, and autoimmunity. Patients with systemic juvenile idiopathic arthritis and adult-onset Still’s disease exhibit chronic excess of serum IL-18, which is associated with a high incidence of macrophage activation syndrome (MAS), although the mechanisms of IL-18 regulation in such diseases remain largely unknown. Similar elevation of serum IL-18 and susceptibility to MAS/hemophagocytic lymphohistiocytosis (HLH) have been reported in monogenic diseases such as X-linked inhibitor of apoptosis deficiency (i.e., X-linked lymphoproliferative syndrome type 2) and NLRC4-associated autoinflammatory disease. Recent advances in molecular and cellular biology allow the identification of other genetic defects such as defects in CDC42, PSTPIP1, and WDR1 that result in high serum IL-18 levels and hyperinflammation. Among these diseases, chronic excess of serum IL-18 appears to be linked with severe hyperinflammation and/or predisposition to MAS/HLH. In this review, we focus on recent findings in inflammatory diseases associated with and probably attributable to chronic excess of serum IL-18 and describe the clinical and therapeutical relevance of understanding the pathology of this group of diseases.

Application and prospect of targeting innate immune sensors in the treatment of autoimmune diseases

Dysregulation of auto-reactive T cells and autoantibody-producing B cells and excessive inflammation are responsible for the occurrence and development of autoimmune diseases. The suppression of autoreactive T cell activation and autoantibody production, as well as inhibition of inflammatory cytokine production have been utilized to ameliorate autoimmune disease symptoms. However, the existing treatment strategies are not sufficient to cure autoimmune diseases since patients can quickly suffer a relapse following the end of treatments. Pattern recognition receptors (PRRs), including Toll-like receptors (TLRs), Nod-like receptors (NLRs), RIG-I like receptors (RLRs), C-type lectin receptors (CLRs) and various nucleic acid sensors, are expressed in both innate and adaptive immune cells and are involved in the development of autoimmune diseases. Here, we have summarized advances of PRRs signaling pathways, association between PRRs and autoimmune diseases, application of inhibitors targeting PRRs and the corresponding signaling molecules relevant to strategies targeting autoimmune diseases. This review emphasizes the roles of different PRRs in activating both innate and adaptive immunity, which can coordinate to trigger autoimmune responses. The review may also prompt the formulation of novel ideas for developing therapeutic strategies against autoimmune diseases by targeting PRRs-related signals.

Cytokine changes in cerebrospinal fluid and plasma after emergency orthopaedic surgery

Neuroinflammation after surgery and its contribution to peri-operative neurocognitive disorders (PND) is not well understood. Studying the association between central and peripheral cytokines and neuroinflammation is a prelude to the development of treatments for PND. Here, we investigate the hypotheses that there is a greater cytokine response in cerebrospinal fluid (CSF) than plasma after orthopaedic surgery, and that plasma cytokine levels are directly related to CSF cytokine levels, indicating that plasma cytokine levels may have potential as biomarkers of neuroinflammation. Patients admitted with a fractured neck of femur were invited to participate in this study. Participants had a spinal catheter inserted just prior to induction of anaesthesia. Samples of blood and CSF were taken before, immediately after, and on the first day following emergency surgery. The catheter was then removed. Samples were analysed for the presence of ten cytokines by immunoassay. A spinal catheter was successfully inserted in 11 participants during the 18-month study period. Five plasma cytokines (IL-4, IL-6, IL-10, IL-12p70 and IL-13) rose significantly following surgery, whereas all ten CSF cytokines rose significantly (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IFN-γ and TNF-α) (adjusted-p < 0.05). Central (CSF) cytokine levels were consistently higher than their peripheral (plasma) counterparts after surgery, with some patients having a particularly marked neuroinflammatory response. The greatest increases occurred in IL-8 in CSF and IL-6 in plasma. There were significant, strong positive correlations between several of the measured cytokines in the CSF after surgery, but far fewer in plasma. There was no significant correlation between cytokine levels in the plasma and CSF at each of the three time points. To our knowledge, this is the first study to analyse paired samples of plasma and CSF for cytokine levels before and after emergency orthopaedic surgery. This study demonstrates that following surgery for a fractured neck of femur, there is a far greater rise in cytokines in the CSF compared to plasma. The lack of correlation between peripheral and central cytokines suggests measurement of peripheral cytokines are not necessarily related to which patients may have a large neuroinflammatory response.

NLRP12-associated systemic autoinflammatory diseases in children

Systemic autoinflammatory diseases (SAIDs) are a group of monogenic diseases characterized by disordered innate immunity, which causes excessive activation of inflammatory pathways. Nucleotide-binding leucine-rich repeat-containing receptor 12-related autoinflammatory disease (NLRP12-AID) is a newly identified SAID and a rare autosomal dominant disorder caused by mutations in the NLRP12 gene, which is also known as familial cold autoinflammatory syndrome 2 (FCAS2) and mostly occurs in childhood. A total of 33 cases of NLRP12-AID in children and 21 different mutation types have been reported to date. The disease is mainly characterized by periodic fever, accompanied by multisystem inflammatory damage. NLRP12-AID is diagnosed through early clinical identification and genetic detection. Emerging drugs targeting interleukin-1-related inflammatory pathways are expected to change the treatment options and improve the quality of life of pediatric patients. This article aims to summarize the characteristics and pathogenesis of reported NLRP12-AID cases in children and provide ideas for clinical diagnosis and treatment.

Successful Treatment of Covid-19 Associated Cytokine Release Syndrome with Colchicine. A Case Report and Review of Literature

We describe the case of a 42 year old, healthy patient with Covid-19 who despite improvement in his respiratory symptoms developed a mild to moderate cytokine release syndrome (CRS) and an associated monoarticular gout flare. Since the patient refused admission to the hospital and had stable vital signs, we chose to treat him with a safe anti-inflammatory and non-immunosuppressive therapy. To hit two birds with one stone, we considered colchicine, as it has systemic anti-inflammatory effects and is also effective in gout flare. Unexpectedly, 48 hours after treatment, not only did his ongoing fever and toe pain disappear, he also had significant improvements in his general state of health and all his inflammatory markers including fibrinogen, ferritin, D-dimer, and IL-6 levels normalized. To our knowledge, the use of colchicine in Covid-19 and CRS has not been reported. This observation merits the consideration of colchicine as a safe, inexpensive and oral medication for the treatment of mild to moderate CRS in Covid-19 patients. More importantly, in Covid-19 patients with early lung involvement colchicine may be an appropriate candidate to prevent CRS in adjunction with routine antiviral agents. Indeed, multicenter, randomized controlled studies are required to evaluate the benefits of this therapy.

Interfering with interferons: targeting the JAK-STAT pathway in complications of systemic juvenile idiopathic arthritis (SJIA)

Systemic JIA (SJIA) is distinguished from other forms of JIA by the prevalence of the severe, life-threatening complications macrophage activation syndrome (SJIA-MAS) and lung disease (SJIA-LD). Alternative therapeutics are urgently needed, as disease pathogenesis diverges from what is observed in SJIA, and currently available biologics are insufficient. SJIA-MAS, defined by a cytokine storm and dysregulated proliferation of T-lymphocytes, and SJIA-LD which presents with lymphocytic interstitial inflammation and pulmonary alveolar proteinosis, are both thought to be driven by IFNs, in particular the type II IFN-γ. Involvement of IFNs and a possible crosstalk of type I IFNs with existing biologics indicate a distinct role for the JAK-STAT signalling pathway in the pathogenesis of SJIA-MAS and SJIA-LD. Here, we review this role of JAK-STATs and IFNs in SJIA complications and discuss how new insights of ongoing research are shaping future therapeutic advances in the form of JAK inhibitors and antibodies targeting IFNs.

A Potent Leukocyte Transmigration Blocker: GT-73 Showed a Protective Effect against LPS-Induced ARDS in Mice

We recently developed a molecule (GT-73) that blocked leukocyte transendothelial migration from blood to the peripheral tissues, supposedly by affecting the platelet endothelial cell adhesion molecule (PECAM-1) function. GT-73 was tested in an LPS-induced acute respiratory distress syndrome (ARDS) mouse model. The rationale for this is based on the finding that the mortality of COVID-19 patients is partly caused by ARDS induced by a massive migration of leukocytes to the lungs. In addition, the role of tert-butyl and methyl ester moieties in the biological effect of GT-73 was investigated. A human leukocyte, transendothelial migration assay was applied to validate the blocking effect of GT-73 derivatives. Finally, a mouse model of LPS-induced ARDS was used to evaluate the histological and biochemical effects of GT-73. The obtained results showed that GT-73 has a unique structure that is responsible for its biological activity; two of its chemical moieties (tert-butyl and a methyl ester) are critical for this effect. GT-73 is a prodrug, and its lipophilic tail covalently binds to PECAM-1 via Lys536. GT-73 significantly decreased the number of infiltrating leukocytes in the lungs and reduced the inflammation level. Finally, GT-73 reduced the levels of IL-1β, IL-6, and MCP-1 in bronchoalveolar lavage fluid (BALF). In summary, we concluded that GT-73, a blocker of white blood cell transendothelial migration, has a favorable profile as a drug candidate for the treatment of ARDS in COVID-19 patients.

Autoimmune and Autoinflammatory Pericarditis: Definitions and New Treatments

PURPOSE OF THE REVIEW

The purpose of the review is to analyze the pathogenetic mechanisms that underlie acute pericarditis, with attention to autoimmune and autoinflammatory pericarditis, and, in addition, to review the available therapeutic armamentarium.

RECENT FINDINGS

Several studies have been published on the use of anti-IL-1 drugs in recurrent pericarditis, including anakinra and rilonacept. The latest, the RHAPSODY study, based on the use of rilonacept in recurrent pericarditis, has recently reached phase 3 with promising results in terms of efficacy and safety. Alterations in the function of the inflammasome and the consequent overproduction of IL-1 play a pivotal role in the genesis of autoinflammatory pericarditis. Recent studies added evidence to the importance of anti-IL-1 drugs in the treatment of recurrent pericarditis with raised C-reactive protein. In the era of tailored medicine, anti-IL-1 agents may be very useful in the subset of patients with recurrent pericarditis and a clear inflammatory phenotype.

Biological treatment in resistant adult-onset Still’s disease: A single-center, retrospective cohort study

Objectives

The aim of this study was to assess the demographic and clinical characteristics of patients with adult-onset Still’s disease (AOSD) under biological treatment.

Patients and methods

This retrospective cohort study included a total of 19 AOSD patients (13 males, 6 females; median age: 37 years; range, 28 to 52 years) who received biological drugs due to refractory disease between January 2008 and January 2020. The data of the patients were obtained from the patient files. The response to the treatment was evaluated based on clinical and laboratory assessments at third and sixth follow-up visits.

Results

Interleukin (IL)-1 inhibitor was prescribed for 13 (68.4%) patients and IL-6 inhibitor prescribed for six (31.6%) patients. Seventeen (89.5%) patients experienced clinical remission.

Conclusion

Biological drugs seem to be effective for AOSD patients who are resistant to conventional therapies. Due to the administration methods and the high costs of these drugs, however, tapering the treatment should be considered, after remission is achieved.

COVID-19 in patients with familial Mediterranean fever treated with colchicine: case based review

Coronavirus disease 2019 (COVID-19) refers to the clinical picture of an important and severe infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Considering the current knowledge on the pathophysiology and clinical manifestations of COVID-19, it is safe to state that both COVID-19 and inflammatory rheumatic disorders cause a cytokine storm and merit treatment with anti-rheumatic drugs. Three patients, who were on regular follow-up due to the diagnosis of familial Mediterranean fever (FMF), contracted COVID-19 infection; and their pre-clinical and post-clinical data as well as laboratory, prognosis and treatment data were investigated. Effects of colchicine in FMF patients who contracted COVID-19 infection were presented in this study. All the cases recovered from COVID-19 without complications. The present study suggests that colchicine can positively affect the prognosis of COVID-19 in FMF patients; therefore, experience of rheumatologists in the use of anti-inflammatory drugs can be highly instrumental in management of COVID-19 patients.

Distinct Gene Expression Signatures Characterize Strong Clinical Responders Versus Nonresponders to Canakinumab in Children With Systemic Juvenile Idiopathic Arthritis

OBJECTIVE

Canakinumab is a human anti-interleukin-1β (anti-IL-1β) blocking agent that effectively neutralizes IL-1β-mediated signaling for treatment of systemic juvenile idiopathic arthritis (JIA). While many patients have dramatic clinical response to IL-1 blockade, approximately one-third fail to respond, but there are currently no validated clinical or immunologic predictors of response. We undertook this study to characterize distinct gene signatures for treatment response and nonresponse to canakinumab in systemic JIA patients.

METHODS

We performed a secondary analysis of whole-blood gene expression microarrays using blood samples obtained from healthy controls and systemic JIA patients at baseline and on day 3 after canakinumab treatment (GEO accession no. GSE80060). Patients were considered strong clinical responders if they met the ACR90 response (exhibited ≥90% improvement in the American College of Rheumatology [ACR] JIA response criteria; nonresponders were those who met ACR30 [exhibiting ≤30% improvement in the ACR JIA response criteria]). A random-effects model with patient identity as the random variable was used for differential expression analysis.

RESULTS

We identified a distinct gene expression signature in patients with a strong clinical response to canakinumab treatment as compared to nonresponders, mediated by up-regulation of neutrophil- and IL-1-associated genes and characterized by increasing divergence from control transcriptomes with increasing clinical response. We also identified a signature including up-regulated CD163 expression that was associated with canakinumab nonresponse. Intriguingly, canakinumab treatment induced either up- or down-regulation of type I interferon (IFN) genes, independent of clinical response.

CONCLUSION

Here, we identify a gene signature in systemic JIA patients prior to receiving treatment that distinguishes strong responders to canakinumab from nonresponders. Further prospective studies are needed to assess the utility of these insights for treatment decisions in systemic JIA and to track the association of up-regulated type I IFN signatures with systemic JIA complications.

Cytokines in Febrile Diseases

The human body has a perfect thermoregulatory system to meet the needs of normal life activities. The central regulation of body temperature is mainly explained by the theory of "setting point (setpoint, SP)". Fever is a positive but nonspecific response of the body to infections and other pyrogens, which causes immune cells to release cytokines, leading to a brain protein-mediated rise in body temperature. Cytokines can be roughly divided into 2 categories: proinflammatory cytokines and anti-inflammatory cytokines. IL-1, TNF-α, and IL-6 are proinflammatory cytokines, whereas IL-4 and IL-10 are anti-inflammatory cytokines. IL-2 is a cytokine that can both activate and inhibit immunity. IL-8 is a neutrophil chemotactic factor, and IFN is a cytokine that plays a key role in the proper induction and maintenance of innate and acquired immunity. This article reviews the pathophysiological characteristics of fever and the cytokines related to fever (IL-2, 4, 6, 8, 10, IFN, TNF, etc.).

Clinical characteristics and comorbidities in adult-onset Still's disease using a large US administrative claims database

OBJECTIVES

We aimed to describe clinical characteristics, treatment patterns and major comorbidities of a US-based adult-onset Still's disease (AOSD) cohort.

METHODS

Administrative claims data from Truven MarketScan were collected from 2009 to 2015. An AOSD case was defined as ≥1 M06.1 International Classification of Diseases 10th revision (ICD-10) medical claim code. We extracted data for the AOSD cohort (n = 106) and 1:5 matched controls (n = 530) without AOSD. Outcomes of interest and a novel claims-based set of Yamaguchi criteria were identified by relevant ICD 9th revision (ICD-9) and ICD-10 codes. Bivariate descriptive analyses were conducted on all variables. Comorbidity rates and rate ratios were calculated in AOSD cases and matched controls. Statistical significance of cohort differences was determined to compare AOSD cases and matched controls.

RESULTS

The AOSD cohort, with a mean age of 43.08 (standard deviation, s.d. 13.9) years and with female predominance (68.9%) was observed over a mean of 750.12 (637.6) days. A total of 35.9% of AOSD patients fulfilled claims-based Yamaguchi criteria compared with 0.4% matched controls (P< 0.05). We identified severe AOSD-related complications, including macrophage activation syndrome (4.7%) and acute respiratory distress syndrome (12.3%). Treatment commonly involved systemic glucocorticoids (62.2%), MTX (51%) and anakinra (24.5%). Compared with matched controls, serious infections were significantly increased (rate ratio 2.58, 95% CI: 1.53, 4.37, P = 0.0004), while hyperlipidaemia (0.54, 95% CI: 0.35, 0.85; P = 0.008) and obesity (0.30, 95% CI: 0.15, 0.62; P = 0.001) were significantly decreased in AOSD patients.

CONCLUSION

We characterized a first US-based AOSD cohort using a large national administrative claims database, and identified key complications, treatments and comorbidities.

Elevated circulating pro-inflammatory low-density granulocytes in adult-onset Still’s disease

Objectives

Neutrophilia is a hallmark of adult-onset Still’s disease (AOSD). This study aimed to investigate the role of a distinct subset of granulocytes, the low-density granulocytes (LDGs) in the pathogenesis of AOSD.

Methods

A total of 56 patients with AOSD were included in the study. LDGs were quantified by flow cytometry. Correlations between LDGs with disease activity and laboratory parameters were determined by Spearman’s nonparametric test. The cellular sources of the pro-inflammatory cytokines in AOSD were determined by intracellular staining.

Results

Active AOSD patients displayed significantly higher levels of LDGs compared with inactive AOSD patients and healthy controls (HCs) (P&lt;0.001). Circulating LDGs were significantly correlated with CRP, ESR and the modified Pouchot score in patients with AOSD (P&lt;0.01). The levels of LDGs were significantly decreased after the active AOSD patients achieved disease remission (P=0.0391). CD14+ monocytes constituted over 90% IL-1β+ peripheral blood mononuclear cells (PBMCs) and over 80% TNF-α+ PBMCs in both active AOSD patients and HCs, respectively. In active AOSD, CD14+ monocytes accounted for 24.6% to 75.0% of IL-6+ PBMCs, while LDGs comprised 22.8% to 72.2% of IL-6+ PBMCs. In contrast, over 90% IL-6+ PBMCs were CD14+ monocytes in HCs. A significant correlation was identified between the levels of LDGs and serum IL-6 levels in AOSD (P&lt;0.0001).

Conclusion

Active AOSD is associated with elevated levels of a pro-inflammatory subset of neutrophils, the LDGs that produce IL-6. Our data highlight an unappreciated role of LDGs in the aberrant innate immune responses in AOSD.

NLRP3 inflammasome priming: A riddle wrapped in a mystery inside an enigma

The NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome is an immunological sensor that detects a wide range of microbial- and host-derived signals. Inflammasome activation results in the release of the potent pro-inflammatory cytokines IL-1β and IL-18 and triggers a form of inflammatory cell death known as pyroptosis. Excessive NLRP3 activity is associated with the pathogenesis of a wide range of inflammatory diseases, thus NLRP3 activation mechanisms are an area of intensive research. NLRP3 inflammasome activation is a tightly regulated process that requires both priming and activation signals. In particular, recent research has highlighted the highly complex nature of the priming step, which involves transcriptional and posttranslational mechanisms, and numerous protein binding partners. This review will describe the current understanding of NLRP3 priming and will discuss the potential opportunities for targeting this process therapeutically to treat NLRP3-associated diseases.

Canakinumab for Treatment of Adult-Onset Still's Disease to Achieve Reduction of Arthritic Manifestation (CONSIDER): phase II, randomised, double-blind, placebo-controlled, multicentre, investigator-initiated trial

BACKGROUND

Inhibition of interleukin (IL)-1 represents a promising treatment option in adult-onset Still's disease (AOSD).

OBJECTIVE

To investigate the efficacy and safety of canakinumab in patients with AOSD and active joint involvement by means of a multicentre, double-blind, randomised, placebo-controlled trial.

METHODS

Patients with AOSD and active joint involvement (tender and swollen joint counts of ≥4 each) were treated with canakinumab (4 mg/kg, maximum 300 mg subcutaneous every 4 weeks) or placebo. The primary endpoint was the proportion of patients with a clinically relevant reduction in disease activity at week 12 as determined by the change in disease activity score (ΔDAS28>1.2).

RESULTS

At enrolment, patients had high active disease with a mean DAS28(ESR) of 5.4 in the canakinumab and 5.3 in the placebo group, respectively. In the intention-to-treat analysis, 12 patients (67%) in the canakinumab group and 7 patients (41%) in the placebo group fulfilled the primary outcome criterion (p=0.18). In the per-protocol analysis, significantly higher American College of Rheumatology (ACR) 30% (61% vs 20%, p=0.033), ACR 50% (50% vs 6.7%, p=0.009) and ACR 70% (28% vs 0%, p=0.049) response rates were observed in the canakinumab group compared with the placebo group. Two patients in the canakinumab group experienced a serious adverse event.

CONCLUSION

Although the study was terminated prematurely and the primary endpoint was not achieved, treatment with canakinumab led to an improvement of several outcome measures in AOSD. The overall safety findings were consistent with the known profile of canakinumab. Thus, our data support indication for IL-1 inhibition with canakinumab in AOSD.

Single-Chain Soluble Receptor Fusion Proteins as Versatile Cytokine Inhibitors

Cytokines are small secreted proteins that among many functions also play key roles in the orchestration of inflammation in host defense and disease. Over the past years, a large number of biologics have been developed to target cytokines in disease, amongst which soluble receptor fusion proteins have shown some promise in pre-clinical studies. We have previously shown proof-of-concept for the therapeutic targeting of interleukin (IL)-33 in airway inflammation using a newly developed biologic, termed IL-33trap, comprising the ectodomains of the cognate receptor ST2 and the co-receptor IL-1RAcP fused into a single-chain recombinant fusion protein. Here we extend the biophysical and biological characterization of IL-33trap variants, and show that IL-33trap is a stable protein with a monomeric profile both at physiological temperatures and during liquid storage at 4°C. Reducing the N-glycan heterogeneity and complexity of IL-33trap via GlycoDelete engineering neither affects its stability nor its inhibitory activity against IL-33. We also report that IL-33trap specifically targets biologically active IL-33 splice variants. Finally, we document the generation and antagonistic activity of a single-chain IL-4/13trap, which inhibits both IL-4 and IL-13 signaling. Collectively, these results illustrate that single-chain soluble receptor fusion proteins against IL-4, IL-13, and IL-33 are novel biologics that might not only be of interest for research purposes and further interrogation of the role of their target cytokines in physiology and disease, but may also complement monoclonal antibodies for the treatment of allergic and other inflammatory diseases.

Systemic autoinflammatory diseases

Systemic autoinflammatory diseases (SAIDs) are a growing group of disorders caused by a dysregulation of the innate immune system leading to episodes of systemic inflammation. In 1997, MEFV was the first gene identified as disease causing for Familial Mediterranean Fever, the most common hereditary SAID. In most cases, autoinflammatory diseases have a strong genetic background with mutations in single genes. Since 1997 more than 30 new genes associated with autoinflammatory diseases have been identified, affecting different parts of the innate immune system. Nevertheless, for at least 40-60% of patients with phenotypes typical for SAIDs, a distinct diagnosis cannot be met, leading to undefined SAIDs (uSAIDs). However, SAIDs can also be of polygenic or multifactorial origin, with environmental influence modulating the phenotype. The implementation of a disease continuum model combining the adaptive and the innate immune system with autoinflammatory and autoimmune diseases shows the complexity of SAIDs and the importance of new methods to elucidate molecular changes and causative factors in SAIDs. Diagnosis is often based on clinical presentation and genetic testing. The timeline from onset to diagnosis takes up to 7.3 years, highlighting the indisputable need to identify new treatment and diagnostic targets. Recently, other factors are under investigation as additional contributors to the pathogenesis of SAIDs. This review gives an overview of pathogenesis and etiology of SAIDs, and summarizes recent diagnosis and treatment options.

Advances in Disease Mechanisms and Translational Technologies: Clinicopathologic Significance of Inflammasome Activation in Autoimmune Diseases

Autoimmune diseases are characterized by dysregulated immune tolerance to self and inflammatory damage to tissues and organs. The development of inflammation involves multiple innate and adaptive immune pathways. Inflammasomes are multimeric cytosolic protein complexes that form to mediate host immune responses upon recognizing pathogen- or damage-associated molecular patterns via pattern-recognition receptors (PRRs). The accelerating pace of inflammasome research has demonstrated important roles for inflammasome activation in many pathologic conditions, including infectious, metabolic, autoinflammatory, and autoimmune diseases. The inflammasome generally comprises a PRR, procaspase 1, and an adaptor molecule connecting the PRR and procaspase 1. Upon inflammasome activation, procaspase 1 becomes active caspase 1 that converts pro-interleukin-1β (proIL-1β) and proIL-18 into mature and active IL-1β and IL-18, respectively. The cytokines IL-1β and IL-18 have multipotent effects on immune and nonimmune cells and induce and promote systemic and local inflammatory responses. Human studies have shown increased levels of these cytokines, altered activation of inflammasome-related molecules, and/or the presence of inflammasome activators in rheumatic diseases, including systemic lupus erythematosus, rheumatoid arthritis, crystal-induced arthropathies, and Sjögren's syndrome. Such changes are found in the primary target organs, such as the kidneys, joints, and salivary glands, as well as in the cardiovascular system. In animal models of rheumatic diseases, inflammation and tissue damage improve upon genetic or pharmacologic targeting of the inflammasome, supporting its pathogenic role. Herein, we review the clinicopathologic significance and therapeutic targeting of inflammasome activation in rheumatic diseases and related conditions based on recent findings.

Update on the management of colchicine resistant Familial Mediterranean Fever (FMF)

BACKGROUND

Familial Mediterranean Fever (FMF), an autoinflammatory disease, is characterized by self-limited inflammatory attacks of fever and polyserositis along with high acute phase response. Although colchicine remains the mainstay in treatment, intolerance and resistance in a certain portion of patients have been posing a problem for physicians.

MAIN BODY

Like many autoimmune and autoinflammatory diseases, many colchicine-resistant or intolerant FMF cases have been successfully treated with biologics. In addition, many studies have tested the efficacy of biologics in treating FMF manifestations.

CONCLUSION

Since carriers of FMF show significantly elevated levels of serum TNF alpha, IL-1, and IL-6, FMF patients who failed colchicine were successfully treated with anti IL-1, anti IL-6, or TNF inhibitors drugs. It is best to use colchicine in combination with biologics.

[New directions of pharmacotherapy of immune - inflammatory rheumatic diseases]

Deciphering immunopathogenesis, expanding the scope of diagnostics and developing new methods for treating human autoimmune diseases are among the priority areas of XXI century medicine. Particularly widely autoimmune pathology is presented in immunoinflammatory rheumatic diseases (IIRD), such as rheumatoid arthritis, systemic lupus erythematosus, systemic scleroderma, systemic vasculitis associated with the synthesis of antineutrophilic cytoplasmic antibodies, Sjogren's syndrome, idiopathic inflammatory myopathies and other other types of others. Deciphering the pathogenesis mechanisms of IIRD created the prerequisites for improving pharmacotherapy, which in the future should lead to a dramatic improvement in the prognosis for these diseases. The review discusses new approaches to IIRD pharmacotherapy associated with the inhibition of tumor necrosis factor-α, interleukin-6 (IL-6), IL-1β, IL-17, IL-23, and the prospects for using Janus kinase inhibitors, depending on the prevailing pathogenesis mechanisms - autoimmunity or autoinflammation.