Perception of self: distinguishing autoimmunity from autoinflammation

Disease activity drives divergent epigenetic and transcriptomic reprogramming of monocyte subpopulations in systemic lupus erythematosus

OBJECTIVES

Systemic lupus erythematosus (SLE) is characterised by systemic inflammation involving various immune cell types. Monocytes, pivotal in promoting and regulating inflammation in SLE, differentiate from classic monocytes into intermediate and non-classic monocytes, assuming diverse roles and changing their proportions in inflammation. In this study, we investigated the epigenetic and transcriptomic profiles of these and novel monocyte subsets in SLE in relation to activity and progression.

METHODS

We obtained the DNA methylomes and transcriptomes of classic, intermediate, non-classic monocytes in patients with SLE (at first and follow-up visits) and healthy donors. We integrated these data with single-cell transcriptomics of SLE and healthy donors and interrogated their relationships with activity and progression.

RESULTS

In addition to shared DNA methylation and transcriptomic alterations associated with a strong interferon signature, we identified monocyte subset-specific alterations, especially in DNA methylation, which reflect an impact of SLE on monocyte differentiation. SLE classic monocytes exhibited a proinflammatory profile and were primed for macrophage differentiation. SLE non-classic monocytes displayed a T cell differentiation-related phenotype, with Th17-regulating features. Changes in monocyte proportions, DNA methylation and expression occurred in relation to disease activity and involved the STAT pathway. Integration of bulk with single-cell RNA sequencing datasets revealed disease activity-dependent expansion of SLE-specific monocyte subsets, further supported the interferon signature for classic monocytes, and associated intermediate and non-classic populations with exacerbated complement activation.

CONCLUSIONS

Disease activity in SLE drives a subversion of the epigenome and transcriptome programme in monocyte differentiation, impacting the function of different subsets and allowing to generate predictive methods for activity and progression.

Interleukin-1 Blockers in Recurrent and Acute Pericarditis: State of the Art and Future Directions

Diseases of the pericardium encompass a spectrum of conditions, including acute and recurrent pericarditis, where inflammation plays a pivotal role in the pathogenesis and clinical manifestations. Anti-inflammatory therapy indeed forms the cornerstone of treating these conditions: NSAIDs, colchicine, and corticosteroids (as a second-line treatment) are recommended by current guidelines. However, these medications come with several contraindications and are not devoid of adverse effects. In recent years, there has been an increased focus on the role of the inflammasome and potential therapeutic targets. Recurrent pericarditis also shares numerous characteristics with other autoinflammatory diseases, in which interleukin-1 antagonists have already been employed with good efficacy and safety. The objective of this review is to summarize the available studies on the use of anti-IL-1 drugs both in acute and recurrent pericarditis.

Multi-Omics Approach to Improved Diagnosis and Treatment of Atopic Dermatitis and Psoriasis

Psoriasis and atopic dermatitis fall within the category of cutaneous immune-mediated inflammatory diseases (IMIDs). The prevalence of IMIDs is increasing in industrialized societies, influenced by both environmental changes and a genetic predisposition. However, the exact immune factors driving these chronic, progressive diseases are not fully understood. By using multi-omics techniques in cutaneous IMIDs, it is expected to advance the understanding of skin biology, uncover the underlying mechanisms of skin conditions, and potentially devise precise and personalized approaches to diagnosis and treatment. We provide a narrative review of the current knowledge in genomics, epigenomics, and proteomics of atopic dermatitis and psoriasis. A literature search was performed for articles published until 30 November 2023. Although there is still much to uncover, recent evidence has already provided valuable insights, such as proteomic profiles that permit differentiating psoriasis from mycosis fungoides and β-defensin 2 correlation to PASI and its drop due to secukinumab first injection, among others.

Nanomedicine-mediated regulated cell death in cancer immunotherapy

Immunotherapy has attracted widespread attention in cancer treatment and has achieved considerable success in the clinical treatment of some tumors, but it has a low response rate in most tumors. To achieve sufficient activation of the immune response, significant efforts using nanotechnology have been made to enhance cancer immune response. In recent years, the induction of various regulated cell death (RCD) has emerged as a potential antitumor immuno-strategy, including processes related to apoptosis, autophagy, necroptosis, pyroptosis, ferroptosis, and cuproptosis. In particular, damage-associated molecular patterns (DAMPs) released from the damaged membrane of dying cells act as in situ adjuvants to trigger antigen-specific immune responses by the exposure of an increased antigenicity. Thus, RCD-based immunotherapy offers a new approach for enhancing cancer treatment efficacy. Furthermore, incorporation with multimodal auxiliary therapies in cell death-based immunotherapy can trigger stronger immune responses, resulting in more efficient therapeutic outcome. This review discusses different RCD modalities and summarizes recent nanotechnology-mediated RCDs in cancer immunotherapy.

Clinical utility of measuring CD4+ T follicular cells in patients with immune dysregulation

Mechanistic studies of autoimmune disorders have identified circulating T follicular helper (cTfh) cells as drivers of autoimmunity. However, the quantification of cTfh cells is not yet used in clinical practice due to the lack of age-stratified normal ranges and the unknown sensitivity and specificity of this test for autoimmunity. We enrolled 238 healthy participants and 130 patients with common and rare disorders of autoimmunity or autoinflammation. Patients with infections, active malignancy, or any history of transplantation were excluded. In 238 healthy controls, median cTfh percentages (range 4.8%-6.2%) were comparable among age groups, sexes, races, and ethnicities, apart from a significantly lower percentages in children less than 1 year of age (median 2.1%, CI: 0.4%-6.8, p < 0.0001). Among 130 patients with over 40 immune regulatory disorders, a cTfh percentage exceeding 12% had 88% sensitivity and 94% specificity for differentiating disorders with adaptive immune cell dysregulation from those with predominantly innate cell defects. This threshold had a sensitivity of 86% and specificity of 100% for active autoimmunity and normalized with effective treatment. cTfh percentages exceeding 12% distinguish autoimmunity from autoinflammation, thereby differentiating two endotypes of immune dysregulation with overlapping symptoms and different therapies.

Multimodal repertoire analysis unveils B cell biology in immune-mediated diseases

OBJECTIVES

Despite the involvement of B cells in the pathogenesis of immune-mediated diseases (IMDs), biological mechanisms underlying their function are scarcely understood. To overcome this gap, here we constructed and investigated a large-scale repertoire catalogue of five B cell subsets of patients with IMDs.

METHODS

We mapped B cell receptor regions from RNA sequencing data of sorted B cell subsets. Our dataset consisted of 595 donors under IMDs and health. We characterised the repertoire features from various aspects, including their association with immune cell transcriptomes and clinical features and their response to belimumab treatment.

RESULTS

Heavy-chain complementarity-determining region 3 (CDR-H3) length among naïve B cells was shortened among autoimmune diseases. Strong negative correlation between interferon signature strength and CDR-H3 length was observed in naïve B cells and suggested the role for interferon in premature B cell development. VDJ gene usage was skewed especially in plasmablasts and unswitched-memory B cells of patients with systemic lupus erythematosus (SLE). We developed a scoring system to quantify this skewing, and it positively correlated with peripheral helper T cell transcriptomic signatures and negatively correlated with the amount of somatic hyper mutations in plasmablasts, suggesting the association of extrafollicular pathway. Further, this skewing led to high usage of IGHV4-34 gene with 9G4 idiotypes in unswitched-memory B cells, which showed a prominent positive correlation with disease activity in SLE. Gene usage skewing in unswitched-memory B cells was ameliorated after belimumab treatment.

CONCLUSIONS

Our multimodal repertoire analysis enabled us the system-level understanding of B cell abnormality in diseases.

What General Neurologists Should Know about Autoinflammatory Syndromes?

Autoinflammatory disorders encompass a wide range of conditions with systemic and neurological symptoms, which can be acquired or inherited. These diseases are characterized by an abnormal response of the innate immune system, leading to an excessive inflammatory reaction. On the other hand, autoimmune diseases result from dysregulation of the adaptive immune response. Disease flares are characterized by systemic inflammation affecting the skin, muscles, joints, serosa, and eyes, accompanied by unexplained fever and elevated acute phase reactants. Autoinflammatory syndromes can present with various neurological manifestations, such as aseptic meningitis, meningoencephalitis, sensorineural hearing loss, and others. Early recognition of these manifestations by general neurologists can have a significant impact on the prognosis of patients. Timely and targeted therapy can prevent long-term disability by reducing chronic inflammation. This review provides an overview of recently reported neuroinflammatory phenotypes, with a specific focus on genetic factors, clinical manifestations, and treatment options. General neurologists should have a good understanding of these important diseases.

Paradigm Shift in Diagnosis and Targeted Therapy in Recurrent Pericarditis

PURPOSE OF THE REVIEW

We review the pathophysiology, diagnosis, and contemporary treatment for recurrent pericarditis, with focus on interleukin-1 (IL-1) inhibitors.

RECENT FINDINGS

Recurrent pericarditis occurs in about 15-30% of patients who have acute pericarditis. With increased understanding of the autoinflammatory pathophysiology of recurrent pericarditis, IL-1 inhibitors including anakinra, canakinumab, and rilonacept have been applied to this condition with great promise. In particular, the RHAPSODY trial found rilonacept significantly improves pain and inflammation, while also reducing recurrence with few adverse events. The next IL-1 inhibitor on the block for pericarditis, goflikicept, is also discussed. Understanding the role of the inflammasome via the autoinflammatory pathway in pericarditis has led to incorporation of IL-1 inhibitors in the treatment of recurrent pericarditis, with proven efficacy and safety and randomized trials. This will lead to increase uptake of this agent which demonstrated lower rates of recurrence and faster time to resolution.

Unveiling the dark side of glucose-regulated protein 78 (GRP78) in cancers and other human pathology: a systematic review

Glucose-Regulated Protein 78 (GRP78) is a chaperone protein that is predominantly expressed in the lumen of the endoplasmic reticulum. GRP78 plays a crucial role in protein folding by assisting in the assembly of misfolded proteins. Under cellular stress conditions, GRP78 can translocate to the cell surface (csGRP78) were it interacts with different ligands to initiate various intracellular pathways. The expression of csGRP78 has been associated with tumor initiation and progression of multiple cancer types. This review provides a comprehensive analysis of the existing evidence on the roles of GRP78 in various types of cancer and other human pathology. Additionally, the review discusses the current understanding of the mechanisms underlying GRP78's involvement in tumorigenesis and cancer advancement. Furthermore, we highlight recent innovative approaches employed in downregulating GRP78 expression in cancers as a potential therapeutic target.

Rilonacept and Other Interleukin-1 Inhibitors in the Treatment of Recurrent Pericarditis

Pericarditis is the commonest form of pericardial disease. Unfortunately, despite optimal treatment, approximately 15-30% of patients with acute pericarditis have recurrence. Many of these patients are refractory to colchicine, and become corticosteroid-dependent. Recurrent pericarditis severely impairs quality of life, and is associated with significant morbidity. Inflammasome formation and overproduction of interleukin (IL)-1 have been found to drive the systemic inflammatory response in recurrent autoinflammatory pericarditis. Several IL-1 inhibitors have been evaluated for their usefulness as therapeutic options. Rilonacept is a dimeric fusion protein that functions as a soluble decoy receptor that binds to both IL-1α and IL-1β, thereby inhibiting the IL-1 pathway. It is safe and efficacious in the treatment of recurrent pericarditis in the RHAPSODY II and III trials. Anakinra is a recombinant IL-1 receptor antagonist that blocks the action of circulating IL-1α and IL-1β. It has also been shown to be safe and efficacious in the AIRTRIP and IRAP studies. Canakinumab is a selective human monoclonal antibody against IL-1β, and data on its use in recurrent pericarditis is scarce. Several questions regarding IL-1 inhibitor therapy, such as the duration of treatment and the recommended tapering protocols, as well as their use in special populations like pregnant or lactating women, remain unanswered and need to be addressed in future studies.

Clinical utility of measuring CD4 + T follicular cells in patients with immune dysregulation

Mechanistic studies of autoimmune disorders have identified circulating T follicular helper (cTfh) cells as drivers of autoimmunity. However, the quantification of cTfh cells is not yet used in clinical practice due to the lack of age-stratified normal ranges and the unknown sensitivity and specificity of this test for autoimmunity. We enrolled 238 healthy participants and 130 patients with common and rare disorders of autoimmunity or autoinflammation. Patients with infections, active malignancy, or any history of transplantation were excluded. In 238 healthy controls, median cTfh percentages (range 4.8% - 6.2%) were comparable among age groups, sexes, races, and ethnicities, apart from a significantly lower percentages in children less than 1 year of age (median 2.1%, CI: 0.4% - 6.8, p< 0.0001). Among 130 patients with over 40 immune regulatory disorders, a cTfh percentage exceeding 12% had 88% sensitivity and 94% specificity for differentiating disorders with adaptive immune cell dysregulation from those with predominantly innate cell defects. This threshold had a sensitivity of 86% and specificity of 100% for active autoimmunity and normalized with effective treatment. cTfh percentages exceeding 12% distinguish autoimmunity from autoinflammation, thereby differentiating two endotypes of immune dysregulation with overlapping symptoms and different therapies.

Dysregulation of miRNA-30e-3p targeting IL-1β in an international cohort of systemic autoinflammatory disease patients

Autoinflammation is the standard mechanism seen in systemic autoinflammatory disease (SAID) patients. This study aimed to investigate the effect of a candidate miRNA, miR-30e-3p, which was identified in our previous study, on the autoinflammation phenotype seen in SAID patients and to analyze its expression in a larger group of European SAID patients. We examined the potential anti-inflammatory effect of miR-30e-3p, which we had defined as one of the differentially expressed miRNAs in microarray analysis involved in inflammation-related pathways. This study validated our previous microarray results of miR-30e-3p in a cohort involving European SAID patients. We performed cell culture transfection assays for miR-30e-3p. Then, in transfected cells, we analyzed expression levels of pro-inflammatory genes; IL-1β, TNF-α, TGF-β, and MEFV. We also performed functional experiments, caspase-1 activation by fluorometric assay kit, apoptosis assay by flow cytometry, and cell migration assays by wound healing and filter system to understand the possible effect of miR-30e-3p on inflammation. Following these functional assays, 3'UTR luciferase activity assay and western blotting were carried out to identify the target gene of the aforementioned miRNA. MiR-30e-3p was decreased in severe European SAID patients like the Turkish patients. The functional assays associated with inflammation suggested that miR-30e-3p has an anti-inflammatory effect. 3'UTR luciferase activity assay demonstrated that miR-30e-3p directly binds to interleukin-1-beta (IL-1β), one of the critical molecules of inflammatory pathways, and reduces both RNA and protein levels of IL-1β. miR-30e-3p, which has been associated with IL-1β, a principal component of inflammation, might be of potential diagnostic and therapeutic value for SAIDs. KEY MESSAGES: miR-30e-3p, which targets IL-1β, could have a role in the pathogenesis of SAID patients. miR-30e-3p has a role in regulating inflammatory pathways like migration, caspase-1 activation. miR-30e-3p has the potential to be used for future diagnostic and therapeutic approaches.

Microbial and Host Metabolites at the Backstage of Fever: Current Knowledge about the Co-Ordinate Action of Receptors and Molecules Underlying Pathophysiology and Clinical Implications

Fever represents an elevation of body temperature, that exerts a protective effect against pathogens. Innate immune cells and neurons are implicated in the regulation of body temperature. Pathogen-associated molecular patterns, i.e., lipopolysaccharides from Gram-negative bacteria and peptidoglycan and lipoteichoic acid from Gram-positive bacteria are exogenous pyrogens, that bind to Toll-like receptors on immune and non-immune cells. The subsequent release of pro-inflammatory cytokines [interleukin-1 (IL-1), IL-6 and Tumor necrosis factor-alpha] and their passage through the brain trigger the febrile response. In fact, neurons of the pre-optic area produce prostaglandin E2 (PGE2), that, in turn, bind to the PGE2 receptors; thus, generating fever. Apart from classical non-steroidal anti-inflammatory drugs, i.e., aspirin and acetaminophen, various botanicals are currently used as antipyretic agents and, therefore, their mechanisms of action will be elucidated.

Regulation of immunological tolerance by the p53-inhibitor iASPP

Maintenance of immunological homeostasis between tolerance and autoimmunity is essential for the prevention of human diseases ranging from autoimmune disease to cancer. Accumulating evidence suggests that p53 can mitigate phagocytosis-induced adjuvanticity thereby promoting immunological tolerance following programmed cell death. Here we identify Inhibitor of Apoptosis Stimulating p53 Protein (iASPP), a negative regulator of p53 transcriptional activity, as a regulator of immunological tolerance. iASPP-deficiency promoted lung adenocarcinoma and pancreatic cancer tumorigenesis, while iASPP-deficient mice were less susceptible to autoimmune disease. Immune responses to iASPP-deficient tumors exhibited hallmarks of immunosuppression, including activated regulatory T cells and exhausted CD8+ T cells. Interestingly, iASPP-deficient tumor cells and tumor-infiltrating myeloid cells, CD4+, and γδ T cells expressed elevated levels of PD-1H, a recently identified transcriptional target of p53 that promotes tolerogenic phagocytosis. Identification of an iASPP/p53 axis of immune homeostasis provides a therapeutic opportunity for both autoimmune disease and cancer.

Bibliometric analysis of research on immunogenic cell death in cancer

Background: Immunotherapy is changing the way we treat cancer. Immunogenic cell death (ICD) has received considerable attention in the treatments of various cancer types, due to the long-lasting antitumor responses elicited in human body. However, to date, no relevant bibliometric research has been reported.

Methods: Publications related to ICD in cancer research were collected from the Web of Science Core Collection. Using CiteSpace, VOSviewer and an online platform, the analyses of co-author, co-citation, and co-occurrence of terms retrieved from literatures were carried out.

Results: A total of 1,577 publications were included in this study. The global research literatures on ICD in cancer research have been increasing from 2005 to 2021. China, the United States and France dominated in this area and had close collaborations with many countries. Six of the top 10 most contributive institutions were from France. When it comes to author analysis, Kroemer G, Zitvogel L, Kepp O, Garg AD and Galluzzi L were in both the top 10 most productive authors and top 10 most co-cited authors lists. The co-occurring author keywords could be grouped into three clusters: “biomarkers of ICD”, “nanoparticles” and “combination therapy”. In terms of promising hotspots, keywords (author keywords and KeyWords Plus) with recent citation bursts could be summarized into two aspects: “tumor microenvironment” and “nanoparticles”.

Conclusion: Increased attention has been paid to ICD in cancer treatment. However, there are still many unresolved domains in the field of ICD, such as clinical application and molecular mechanisms of this cell death process. ICD-inducing modalities combined with nanotechnology could potentiate the current immunotherapies, and will be hotspots for future research.

Autoimmune and autoinflammatory diseases with mucocutaneous manifestations: A pediatric rheumatology perspective

The presence of mucocutaneous manifestations has clinical significance, as it may be a part of the initial presentation or activation stage of both autoimmune and autoinflammatory rheumatic diseases. The cutaneous signs may display a particular morphological and topographic distribution according to taxonomy, whereas heterogeneity is likely observed among the individuals. The review aims to cluster and systematically approach the mucocutaneous manifestations met in autoimmune and autoinflammatory rheumatic diseases of childhood. The search strategy involved a comprehensive inquiry on Web of Science, PubMed, MEDLINE, and Embase databases using relevant search terms such as "dermatologic, cutaneous, mucocutaneous, skin, rash" for each disease and category. The awareness of the distinctive mucocutaneous manifestations and their correlation with rheumatic diseases provides a convenient definition, well-timed control of the underlying condition, and prevention of cosmetic issues. In the management of rheumatic diseases, planning the pertinent differential diagnosis and determining the requirement of histopathological assessment are essential with a multidisciplinary approach to rheumatology, dermatology, and allergy-immunology specialties.

Optimal use of the FDG-PET/CT in the diagnostic process of fever of unknown origin (FUO): a comprehensive review

Numerous studies have clarified the usefulness of ¹⁸F-fluorodeoxyglucose (FDG)-PET/CT (positron emission tomography) for diagnosing the cause of fever of unknown origin (FUO). Various types of disease can cause FUO, but the cause remains unknown in a certain proportion of FUO, even when the advanced diagnostic methodologies are used. FDG-PET/CT is regarded as a second-line modality in the diagnostic process of FUO, and its potential to identify the cause of FUO will be maximized when the appropriate clinical considerations are understood. Accordingly, this review presents basic knowledge regarding FUO, and reports the current status of FDG-PET/CT applied to diagnosing the cause of FUO, including diagnostic performance, test protocols, possible factors influencing the diagnostic result, outcomes, and cost-effectiveness. This knowledge will enable effective future use of FDG-PET/CT to improve outcomes in patients with FUO.

Metabolic Profiling in Rheumatoid Arthritis, Psoriatic Arthritis, and Psoriasis: Elucidating Pathogenesis, Improving Diagnosis, and Monitoring Disease Activity

Immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis (RA), psoriatic arthritis (PsA), and psoriasis (Ps), represent autoinflammatory and autoimmune disorders, as well as conditions that have an overlap of both categories. Understanding the underlying pathogeneses, making diagnoses, and choosing individualized treatments remain challenging due to heterogeneous disease phenotypes and the lack of reliable biomarkers that drive the treatment choice. In this review, we provide an overview of the low-molecular-weight metabolites that might be employed as biomarkers for various applications, e.g., early diagnosis, disease activity monitoring, and treatment-response prediction, in RA, PsA, and Ps. The literature was evaluated, and putative biomarkers in different matrices were identified, categorized, and summarized. While some of these candidate biomarkers appeared to be disease-specific, others were shared across multiple IMIDs, indicating common underlying disease mechanisms. However, there is still a long way to go for their application in a routine clinical setting. We propose that studies integrating omics analyses of large patient cohorts from different IMIDs should be performed to further elucidate their pathomechanisms and treatment options. This could lead to the identification and validation of biomarkers that might be applied in the context of precision medicine to improve the clinical outcomes of these IMID patients.

Interleukin-1 Antagonists for the Treatment of Recurrent Pericarditis

Although most patients with acute pericarditis will recover, a minority will have recurrent, debilitating episodes. In these patients, refractory symptoms result in high morbidity, and typically require a prolonged duration of anti-inflammatory treatment. Initially, the efficacy of colchicine in both recurrent pericarditis and periodic fever syndromes suggested the central role of the inflammasome in pericarditis. Subsequently, the success of interleukin-1 antagonists in autoinflammatory diseases prompted further investigation in recurrent pericarditis. In current clinical practice, interleukin-1 antagonists include canakinumab, anakinra, and rilonacept. Both anakinra and rilonacept have demonstrated efficacy in randomized trials of patients with recurrent pericarditis. The aim of the current review is to explain the biological rationale for interleukin-1 antagonists in recurrent pericarditis, highlight supporting clinical evidence, and emphasizing future areas of investigation.

Platelet Storage Pool Deficiency and Elevated Inflammatory Biomarkers Are Prevalent in Postural Orthostatic Tachycardia Syndrome

A significant number of postural orthostatic tachycardia syndrome (POTS) patients have platelet delta granule storage pool deficiency (δ-SPD). The etiology of POTS is unknown but a number of laboratories, including ours, have reported elevations of G-protein-coupled adrenergic receptor and muscarinic acetylcholine receptor autoantibodies in POTS patients, detected by a variety of techniques, suggesting that the disorder is an autoimmune condition. Thus, it could also be considered an inflammatory disease. In a pilot study, we investigated a limited number of platelet-related cytokines and chemokines and discovered many that were elevated. This case−control study validates our pilot study results that POTS patients have an activated innate immune system. Plasma of 35 POTS patients and 35 patients with unexplained bleeding symptoms and categorized as “non-POTS” subjects was analyzed by multiplex flow cytometry to quantify 16 different innate immune system cytokines and chemokines. Electron microscopy was used to quantify platelet dense granules. Ten of 16 biomarkers of inflammation were elevated in plasma from POTS patients compared to non-POTS subjects, with most of the differences extremely significant, with p values < 0.0001. Of particular interest were elevations of IL-1β and IL-18 and decreased or normal levels of type 1 interferons in POTS patients, suggesting that the etiology of POTS might be autoinflammatory. All POTS patients had δ-SPD. With a growing body of evidence that POTS is an autoimmune disease and having elevations of the innate immune system, our results suggest a potential T-cell-mediated autoimmunity in POTS characteristic of a mixed-pattern inflammatory disease similar to rheumatoid arthritis.

Rilonacept (Interleukin-1 Inhibition) for the Treatment of Pericarditis

PURPOSE OF REVIEW

We reviewed the contemporary literature and clinical trials to discuss the applications of the interleukin-1 (IL-1) inhibitor rilonacept to treat pericarditis, with regards to pathophysiology, pharmacology, efficacy, and safety.

RECENT FINDINGS

Rilonacept is an emerging novel agent for treating recurrent pericarditis, with phase II and III clinical trials recently published. Rilonacept rapidly resolved pericarditis pain and inflammation, markedly reduced recurrent pericarditis episodes, and had few adverse events indicating a high safety profile. Recurrent pericarditis is associated with significant morbidity and unmet need for novel therapies. Inflammasomes and the IL-1 pathways were found to be critical in its pathophysiology, leading to IL-1 inhibitors being developed. The high efficacy and safety of rilonacept for recurrent pericarditis means it could potentially be considered as a second-line therapy ahead of or as an alternative to corticosteroids, and highlight the great promise of targeted immunomodulatory therapy in this field.

Promise of the NLRP3 Inflammasome Inhibitors in In Vivo Disease Models

Nucleotide-binding oligomerization domain NOD-like receptors (NLRs) are conserved cytosolic pattern recognition receptors (PRRs) that track the intracellular milieu for the existence of infection, disease-causing microbes, as well as metabolic distresses. The NLRP3 inflammasome agglomerates are consequent to sensing a wide spectrum of pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Certain members of the NLR family have been documented to lump into multimolecular conglomerates called inflammasomes, which are inherently linked to stimulation of the cysteine protease caspase-1. Following activation, caspase-1 severs the proinflammatory cytokines interleukin (IL)-1β and IL-18 to their biologically active forms, with consequent commencement of caspase-1-associated pyroptosis. This type of cell death by pyroptosis epitomizes a leading pathway of inflammation. Accumulating scientific documentation has recorded overstimulation of NLRP3 (NOD-like receptor protein 3) inflammasome involvement in a wide array of inflammatory conditions. IL-1β is an archetypic inflammatory cytokine implicated in multiple types of inflammatory maladies. Approaches to impede IL-1β's actions are possible, and their therapeutic effects have been clinically demonstrated; nevertheless, such strategies are associated with certain constraints. For instance, treatments that focus on systemically negating IL-1β (i.e., anakinra, rilonacept, and canakinumab) have been reported to result in an escalated peril of infections. Therefore, given the therapeutic promise of an NLRP3 inhibitor, the concerted escalated venture of the scientific sorority in the advancement of small molecules focusing on direct NLRP3 inflammasome inhibition is quite predictable.

Multi-omics approach to precision medicine for immune-mediated diseases

Recent innovation in high-throughput sequencing technologies has drastically empowered the scientific research. Consequently, now, it is possible to capture comprehensive profiles of samples at multiple levels including genome, epigenome, and transcriptome at a time. Applying these kinds of rich information to clinical settings is of great social significance. For some traits such as cardiovascular diseases, attempts to apply omics datasets in clinical practice for the prediction of the disease risk have already shown promising results, although still under way for immune-mediated diseases. Multiple studies have tried to predict treatment response in immune-mediated diseases using genomic, transcriptomic, or clinical information, showing various possible indicators. For better prediction of treatment response or disease outcome in immune-mediated diseases, combining multi-layer information together may increase the power. In addition, in order to efficiently pick up meaningful information from the massive data, high-quality annotation of genomic functions is also crucial. In this review, we discuss the achievement so far and the future direction of multi-omics approach to immune-mediated diseases.

Mechanisms of Regulated Cell Death: Current Perspectives

Balancing cell survival and cell death is fundamental to development and homeostasis. Cell death is regulated by multiple interconnected signaling pathways and molecular mechanisms. Regulated cell death (RCD) is implicated in fundamental processes such as organogenesis and tissue remodeling, removal of unnecessary structures or cells, and regulation of cell numbers. RCD can also be triggered by exogenous perturbations of the intracellular or extracellular microenvironment when the adaptive processes that respond to stress fail. During the past few years, many novel forms of non-apoptotic RCD have been identified, and the characterization of RCD mechanisms at a molecular level has deepened our understanding of diseases encountered in human and veterinary medicine. Given the complexity of these processes, it has become clear that the identification of RCD cannot be based simply on morphologic characteristics and that descriptive and diagnostic terms presently used by pathologists-such as individual cell apoptosis or necrosis-appear inadequate and possibly misleading. In this review, the current understanding of the molecular machinery of each type of non-apoptotic RCD mechanisms is outlined. Due to the continuous discovery of new mechanisms or nuances of previously described processes, the limitations of the terms apoptosis and necrosis to indicate microscopic findings are also reported. In addition, the need for a standard panel of biomarkers and functional tests to adequately characterize the underlying RCD and its role as a mechanism of disease is considered.

Damage-Associated Molecular Patterns Modulation by microRNA: Relevance on Immunogenic Cell Death and Cancer Treatment Outcome

Simple Summary

Inside the cell, damage-associated molecular pattern molecules (DAMPs) play several physiological functions, but when they are released or translocated to the extracellular space, they gain additional immunogenic roles. Thus, DAMPs are considered key hallmarks of immunogenic cell death (ICD) in cancer, a functionally unique regulated form of stress-mediated cell death that activates the immune system response against tumor cells. Several epigenetic modulators of DAMPs have been reported. In this review, we aimed to provide an overview of the effects of microRNAs (miRNAs) on the expression of DAMPs and the putative link between miRNA, DAMPs, and cell death, focused on ICD. Overall, we propose that miRNAs, by targeting DAMPs, play critical roles in the regulation of both cell death and immune-associated mechanisms in cancer, while evidence of their potential involvement in ICD is limited. Finally, we discuss emerging data regarding the impact of miRNAs’ modulation on cancer treatment outcome.

Abstract

Immunogenic cell death (ICD) in cancer is a functionally unique regulated form of stress-mediated cell death that activates both the innate and adaptive immune response against tumor cells. ICD makes dying cancer cells immunogenic by improving both antigenicity and adjuvanticity. The latter relies on the spatiotemporally coordinated release or exposure of danger signals (DAMPs) that drive robust antigen-presenting cell activation. The expression of DAMPs is often constitutive in tumor cells, but it is the initiating stressor, called ICD-inducer, which finally triggers the intracellular response that determines the kinetics and intensity of their release. However, the contribution of cell-autonomous features, such as the epigenetic background, to the development of ICD has not been addressed in sufficient depth. In this context, it has been revealed that several microRNAs (miRNAs), besides acting as tumor promoters or suppressors, can control the ICD-associated exposure of some DAMPs and their basal expression in cancer. Here, we provide a general overview of the dysregulation of cancer-associated miRNAs whose targets are DAMPs, through which new molecular mediators that underlie the immunogenicity of ICD were identified. The current status of miRNA-targeted therapeutics combined with ICD inducers is discussed. A solid comprehension of these processes will provide a framework to evaluate miRNA targets for cancer immunotherapy.

Crosstalk between Interleukin-1β and Type I Interferons Signaling in Autoinflammatory Diseases

Interleukin-1β (IL-1β) and type I interferons (IFNs) are major cytokines involved in autoinflammatory/autoimmune diseases. Separately, the overproduction of each of these cytokines is well described and constitutes the hallmark of inflammasomopathies and interferonopathies, respectively. While their interaction and the crosstalk between their downstream signaling pathways has been mostly investigated in the frame of infectious diseases, little information on their interconnection is still available in the context of autoinflammation promoted by sterile triggers. In this review, we will examine the respective roles of IL-1β and type I IFNs in autoinflammatory/rheumatic diseases and analyze their potential connections in the pathophysiology of some of these diseases, which could reveal novel therapeutic opportunities.

Dynamic landscape of immune cell-specific gene regulation in immune-mediated diseases

Genetic studies have revealed many variant loci that are associated with immune-mediated diseases. To elucidate the disease pathogenesis, it is essential to understand the function of these variants, especially under disease-associated conditions. Here, we performed a large-scale immune cell gene-expression analysis, together with whole-genome sequence analysis. Our dataset consists of 28 distinct immune cell subsets from 337 patients diagnosed with 10 categories of immune-mediated diseases and 79 healthy volunteers. Our dataset captured distinctive gene-expression profiles across immune cell types and diseases. Expression quantitative trait loci (eQTL) analysis revealed dynamic variations of eQTL effects in the context of immunological conditions, as well as cell types. These cell-type-specific and context-dependent eQTLs showed significant enrichment in immune disease-associated genetic variants, and they implicated the disease-relevant cell types, genes, and environment. This atlas deepens our understanding of the immunogenetic functions of disease-associated variants under in vivo disease conditions.

Bridging autoinflammatory and autoimmune diseases

Background

Autoimmunity is used to cause by impairment of adaptive immunity alone, whereas autoinflammatory was originally defined as a consequence of unregulated innate immunity. So, the pathogenetic mechanisms of autoimmune diseases were well-thought-out to be mediated by B and T lymphocytes. Whereas, autoinflammatory diseases were defined as unprovoked times of inflammation with the absence of a high titre of autoantibodies.

Main body of the abstract

Autoimmune and autoinflammatory diseases were split into two groups, but considering the similarities, it can be considered as only one group of diseases with a large immune pathological and clinical spectrum which involves at one end pure autoimmune diseases and the other pure autoinflammatory diseases.

Conclusions

We can safely conclude that there is bridging between autoinflammatory and autoimmune diseases.

Systemic autoinflammatory disease in adults

Systemic autoinflammatory disorders comprise an expanding group of rare conditions. They are mediated by dysfunction of the innate immune system and share a core of phenotypic manifestations including recurrent attacks of fever, cutaneous signs, chest or abdominal pain, lymphadenopathy, vasculopathy, and musculoskeletal symptoms. Diagnosis is often established in childhood, but a growing number of adult patients are being recognized with systemic autoinflammatory disorders, including adult-onset disease. In this review, we provide a concise update on the pathophysiology, clinical presentation, and diagnostic approach of systemic autoinflammatory disorders with an emphasis on the adult patient population. Despite the recent advances in genetic testing, the diagnosis of autoinflammatory disease in adult patients is often based on a thorough knowledge of the clinical phenotype. Becoming acquainted with the clinical features of these rare disorders may assist in developing a high index of suspicion for autoinflammatory disease in patients presenting with unexplained episodes of fever or inflammation.

Inflammatory Biomarkers in Postural Orthostatic Tachycardia Syndrome with Elevated G-Protein-Coupled Receptor Autoantibodies

A growing body of evidence suggests that postural orthostatic tachycardia syndrome (POTS) may be an autoimmune disorder. We have reported in a previous manuscript that 89% of POTS patients (n = 55) had elevations in G-protein-coupled adrenergic A1 receptor autoantibodies and 53% had elevations in muscarinic acetylcholine M4 receptor autoantibodies, as assessed by ELISA. Patients with autoimmune disorders have been reported with a variety of elevated cytokines and cytokines (such as rheumatoid arthritis); thus, we evaluated a limited number of cytokines/chemokines in POTS patients with elevated adrenergic and muscarinic receptor autoantibodies. We utilized the plasma of 34 patients from a previous study; all of the patients (100%) had autoantibodies against the A1 adrenergic receptor and 55.9% (19/34) had autoantibodies against the M4 muscarinic acetylcholine receptor. In particular, the plasma cytokine/chemokine levels were measured as biomarkers of inflammation by Quantibody® technology (Raybiotech, Peachtree Corners, GA, USA). We also evaluated the platelet dense granule numbers, as these patients frequently complain of symptoms related to platelet dysfunction. Patients were predominantly young females who displayed a multitude of co-morbidities but generally reported viral-like symptoms preceding episodes of syncope. Eighty five percent (29/34) had platelet storage pool deficiency. Patients had elevations in five of ten cytokine/chemokines biomarkers (IL1β, IL21, TNFα, INFγ, and CD30), whereas two biomarkers had decreased levels (CD40L and RANTES). Our observations demonstrate that POTS patients known to have autoantibodies against the G-protein-coupled adrenergic A1 receptor have abnormal plasma concentrations of inflammatory cytokines.

An update on the pathophysiology of acute and recurrent pericarditis

Pericarditis is an inflammatory disease of the pericardium. Progress has been done in recent years in the understanding of its pathophysiology. In particular, pre-clinical and clinical studies have contributed to increasing our knowledge on the role of interleukin (IL)-1 and NLRP3 (NACHT, leucine- rich repeat, and pyrin domain- containing protein 3) inflammasome. Based on current evidence, pericarditis should be considered as an inflammatory reaction to various stimuli, including chemical/physical, infectious, or ischemic ones, with a viral infection being a common etiology. Interaction of pathogens or irritants with toll-like receptor (TLRs) and stimulation of IL-1 receptor by IL-1α and IL-1β lead to an increased transcription of pro-inflammatory genes, including those needed for NLRP3 inflammasome assembly. This pathway is confirmed indirectly by the beneficial effect of colchicine (an indirect NLRP3 inflammasome inhibitor) and IL-1 blockers in patients with recurrent pericarditis. More recently, a direct evidence of the NLRP3 inflammasome within the inflamed pericardium has been provided as well. It may, however, occur that selfantigens on the surface of mesothelial cells or microbial peptides may stimulate autoreactive T cells along with B cells producing anti-heart antibodies, although less evidence is available on this. Some uncertainties still remain about the role of neutrophils, neutrophil extracellular traps (NETs), and pericardial interstitial cells in recurrent and constrictive pericarditis. Unraveling these aspects might have a direct impact on the development of novel targeted therapies, especially considering the increasing number of drugs targeting NETs.

Nanomedicine and Onco-Immunotherapy: From the Bench to Bedside to Biomarkers

The broad relationship between the immune system and cancer is opening a new hallmark to explore for nanomedicine. Here, all the common and synergy points between both areas are reviewed and described, and the recent approaches which show the progress from the bench to the beside to biomarkers developed in nanomedicine and onco-immunotherapy.

Impaired proteolysis by SPPL2a causes CD74 fragment accumulation that can be recognized by anti-CD74 autoantibodies in human ankylosing spondylitis

Ankylosing spondylitis (AS) is associated with autoantibody production to class II MHC‐associated invariant chain peptide, CD74/CLIP. In this study, we considered that anti‐CD74/CLIP autoantibodies present in sera from AS might recognize CD74 degradation products that accumulate upon deficiency of the enzyme signal peptide peptidase‐like 2A (SPPL2a). We analyzed monocytes from healthy controls (n = 42), psoriatic arthritis (n = 25), rheumatoid arthritis (n = 16), and AS patients (n = 15) for SPPL2a enzyme activity and complemented the experiments using SPPL2a‐sufficient and ‐deficient THP‐1 cells. We found defects in SPPL2a function and CD74 processing in a subset of AS patients, which culminated in CD74 and HLA class II display at the cell surface. These findings were verified in SPPL2a‐deficient THP‐1 cells, which showed expedited expression of MHC class II, total CD74 and CD74 N‐terminal degradation products at the plasma membrane upon receipt of an inflammatory trigger. Furthermore, we observed that IgG anti‐CD74/CLIP autoantibodies recognize CD74 N‐terminal degradation products that accumulate upon SPPL2a defect. In conclusion, reduced activity of SPPL2a protease in monocytes from AS predisposes to endosomal accumulation of CD74 and CD74 N‐terminal fragments, which, upon IFN‐γ‐exposure, is deposited at the plasma membrane and can be recognized by anti‐CD74/CLIP autoantibodies.

A clinical score to guide in decision making for monogenic type I IFNopathies

OBJECTIVE

To develop a set of clinical criteria that identifies patients with a potential autoinflammatory IFNopathy.

METHODS

Based on a literature review, a set of clinical criteria identifying genetically confirmed monogenic IFNopathies was selected. For validation, the clinical score was assessed in healthy controls (HCs) and 18 disease controls, including 2 known autoimmune IFNopathies, juvenile systemic lupus erythematosus (JSLE, n = 4) and dermatomyositis (JDM, n = 4); adenosine deaminase 2 deficiency (DADA2, n = 4); and oligoarticular juvenile idiopathic arthritis (oJIA, n = 6). We assessed an IFN score (IRG-S) in whole blood by NanoString using a previously published 28-gene-IRG-S and a reduced 6-gene-IRG-S.

RESULTS

The 12 patients with a possible IFNopathy had higher clinical scores (3-5) than the patients with sJLE, JDM, DADA2, and oJIA and in HCs. Both the 28-IRG-S and 6-IRG-S were significantly higher in the autoinflammatory IFNopathy patients compared to HCs and oJIA and DADA2 patients but not different from patients with JSLE and JDM. Subsequently, genetic analysis revealed mutations in genes previously reported in genes related to the IFN pathway in 9 of the 12 patients.

CONCLUSION

We developed a clinical score to identify patients with possible autoinflammatory IFNopathies. A clinical score was associated with a high IRG-S and may serve to identify patients with an autoinflammatory IFNopathy.

Regulation of cGAS-Mediated Immune Responses and Immunotherapy

Early detection of infectious nucleic acids released from invading pathogens by the innate immune system is critical for immune defense. Detection of these nucleic acids by host immune sensors and regulation of DNA sensing pathways have been significant interests in the past years. Here, current understandings of evolutionarily conserved DNA sensing cyclic GMP-AMP (cGAMP) synthase (cGAS) are highlighted. Precise activation and tight regulation of cGAS are vital in appropriate innate immune responses, senescence, tumorigenesis and immunotherapy, and autoimmunity. Hence, substantial insights into cytosolic DNA sensing and immunotherapy of indispensable cytosolic sensors have been detailed to extend limited knowledge available thus far. This Review offers a critical, in-depth understanding of cGAS regulation, cytosolic DNA sensing, and currently established therapeutic approaches of essential cytosolic immune agents for improved human health.

Additive Therapeutic Effects of Mesenchymal Stem Cells and IL-37 for Systemic Lupus Erythematosus

BACKGROUND

Although mesenchymal stem cells (MSCs) might offer a promising strategy for treating SLE, their immunoregulatory plasticity makes their therapeutic effects unpredictable. Whether overexpressing IL-37, an IL-1 family member with immunosuppressive activity, might enhance the therapeutic effects of these cells for SLE is unknown.

METHODS

We genetically modified MSCs to overexpress IL-37 and assessed their effects on immune suppression in vitro. We also evaluated the effects of such cells versus effects of various controls after transplanting them into MRL/lpr mice (model of SLE).

RESULTS

Stem cell characteristics did not appear altered in MSCs overexpressing IL-37. These cells had enhanced immunosuppression in vitro in terms of inhibiting splenocyte proliferation, reducing proinflammatory factors (IL-1β, TNF-α, IL-17, and IL-6), and suppressing autoantibodies (anti-dsDNA and anti-ANA). Compared with animals receiving control MSCs or IL-37 treatment alone, MRL/lpr mice transplanted with IL-37-overexpressing cells displayed improved survival and reduced signs of SLE (indicated by urine protein levels, spleen weight, and renal pathologic scores); they also had significantly lower expression of proinflammatory factors, lower total antibody levels in serum and urine, lower autoantibody production, and showed reduced T cell numbers in the serum and kidney. Expression of IL-37 by MSCs can maintain higher serum levels of IL-37, and MSCs had prolonged survival after transplantation, perhaps through IL-37 suppressing the inflammatory microenvironment.

CONCLUSIONS

Mutually reinforcing interaction between MSCs and IL-37 appears to underlie their additive therapeutic effects. Genetic modification to overexpress IL-37 might offer a way to enhance the stability and effectiveness of MSCs in treating SLE.

Modulation of autoimmune pathogenesis by T cell-triggered inflammatory cell death

T cell-mediated autoimmunity encompasses diverse immunopathological outcomes; however, the mechanisms underlying this diversity are largely unknown. Dysfunction of the tripartite linear ubiquitin chain assembly complex (LUBAC) is associated with distinct autonomous immune-related diseases. Cpdm mice lacking Sharpin, an accessory subunit of LUBAC, have innate immune cell-predominant dermatitis triggered by death of LUBAC-compromised keratinocytes. Here we show that specific gene ablation of Sharpin in mouse Treg causes phenotypes mimicking cpdm-like inflammation. Mechanistic analyses find that multiple types of programmed cell death triggered by TNF from tissue-oriented T cells initiate proinflammatory responses to implicate innate immune-mediated pathogenesis in this T cell-mediated inflammation. Moreover, additional disruption of the Hoip locus encoding the catalytic subunit of LUBAC converts cpdm-like dermatitis to T cell-predominant autoimmune lesions; however, innate immune-mediated pathogenesis still remains. These findings show that T cell-mediated killing and sequential autoinflammation are common and crucial for pathogenic diversity during T cell-mediated autoimmune responses.

Many forms of autoimmune disorder involve abnormal T cell functions, but how this versatility is achieved is not fully clear. Here the authors show that Sharpin-deficient Treg cells induce the death of local keratinocytes via multiple programmed cell death and innate inflammation to cause skin inflammation similar to cpdm mice with genetic deletion of Sharpin.

Emerging views of mitophagy in immunity and autoimmune diseases

Mitophagy is a vital form of autophagy for selective removal of dysfunctional or redundant mitochondria. Accumulating evidence implicates elimination of dysfunctional mitochondria as a powerful means employed by autophagy to keep the immune system in check. The process of mitophagy may restrict inflammatory cytokine secretion and directly regulate mitochondrial antigen presentation and immune cell homeostasis. In this review, we describe distinctive pathways of mammalian mitophagy and highlight recent advances relevant to its function in immunity. In addition, we further discuss the direct and indirect evidence linking mitophagy to inflammation and autoimmunity underlying the pathogenesis of autoimmune diseases including inflammatory bowel diseases (IBD), systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC).Abbreviations: AICD: activation induced cell death; AIM2: absent in melanoma 2; ALPL/HOPS: alkaline phosphatase, biomineralization associated; AMA: anti-mitochondrial antibodies; AMFR: autocrine motility factor receptor; ATG: autophagy-related; BCL2L13: BCL2 like 13; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CARD: caspase recruitment domain containing; CASP1: caspase 1; CD: Crohn disease; CGAS: cyclic GMP-AMP synthase; CXCL1: C-X-C motif chemokine ligand 1; DEN: diethylnitrosamine; DLAT/PDC-E2: dihydrolipoamide S-acetyltransferase; DNM1L/Drp1: dynamin 1 like; ESCRT: endosomal sorting complexes required for transport; FKBP8: FKBP prolyl isomerase 8; FUNDC1: Fun14 domain containing 1; GABARAP: GABA type A receptor-associated protein; HMGB1: high mobility group box 1; HPIV3: human parainfluenza virus type 3; IBD: inflammatory bowel diseases; IEC: intestinal epithelial cell; IFN: interferon; IL1B/IL-1β: interleukin 1 beta; iNK: invariant natural killer; IRGM: immunity related GTPase M; LIR: LC3-interacting region; LPS: lipopolysaccharide; LRRK2: leucine rich repeat kinase 2; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MARCH5: membrane associated ring-CH-type finger 5; MAVS: mitochondrial antiviral signaling protein; MDV: mitochondria-derived vesicle; MFN1: mitofusin 1; MHC: major histocompatibility complex; MIF: macrophage migration inhibitory factor; mtAP: mitochondrial antigen presentation; mtDNA: mitochondrial DNA; MTOR: mechanistic target of rapamycin kinase; mtROS: mitochondrial ROS; MUL1: mitochondrial E3 ubiquitin protein ligase 1; NBR1: NBR1 autophagy cargo receptor; NFKB/NF-ĸB: nuclear factor kappa B subunit; NK: natural killer; NLR: NOD-like receptor; NLRC4: NLR family CARD domain containing 4; NLRP3: NLR family pyrin domain containing 3; OGDH: oxoglutarate dehydrogenase; OMM: outer mitochondrial membrane; OPTN: optineurin; ox: oxidized; PARK7: Parkinsonism associated deglycase; PBC: primary biliary cirrhosis; PEX13: peroxisomal biogenesis factor 13; PHB/PHB1: prohibitin; PHB2: prohibitin 2; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PINK1: PTEN induced kinase 1; PLEKHM1: pleckstrin homology and RUN domain containing M1; PRKN/PARK2: parkin RBR E3 ubiquitin protein ligase; RAB: member RAS oncogene family; RHEB: Ras homolog: mTORC1 binding; RIPK2: receptor interacting serine/threonine kinase 2; RLR: DDX58/RIG-I like receptor; ROS: reactive oxygen species; SBD: small bile ducts; SLC2A1/GLUT1: solute carrier family 2 member 1; SLE: systemic lupus erythematosus; SMURF1: SMAD specific E3 ubiquitin protein ligase 1; SQSTM1/p62: sequestosome 1; TAX1BP1: Tax1 binding protein 1; TCR: T cell receptor; TFAM: transcription factor A: mitochondrial; Th17: T helper 17; TLR9: toll like receptor 9; TMEM173/STING: transmembrane protein 173; TNF/TNF-α: tumor necrosis factor; Ub: ubiquitin; UC: ulcerative colitis; ULK1: unc-51 like autophagy activating kinase 1; WIPI: WD repeat domain: phosphoinositide interacting; ZFYVE1/DFCP1: zinc finger FYVE-type containing 1.

NLRP3 inflammasome in ischemic stroke: As possible therapeutic target

Inflammation is a devastating pathophysiological process during stroke, a devastating disease that is the second most common cause of death worldwide. Activation of the NOD-like receptor protein (NLRP3)-infammasome has been proposed to mediate inflammatory responses during ischemic stroke. Briefly, NLRP3 inflammasome activates caspase-1, which cleaves both pro-IL-1 and pro-IL-18 into their active pro-inflammatory cytokines that are released into the extracellular environment. Several NLRP3 inflammasome inhibitors have been promoted, including small molecules, type I interferon, micro RNAs, nitric oxide, and nuclear factor erythroid-2 related factor 2 (Nrf2), some of which are potentially efficacious clinically. This review will describe the structure and cellular signaling pathways of the NLRP3 inflammasome during ischemic stroke, and current evidence for NLRP3 inflammasome inhibitors.

Clinical Correlations of Novel Autoantibodies in Patients with Dry Eye

Background

Diagnostic criteria for Sjögren's syndrome (SS) are continually being updated in pursuit of more precise and earlier diagnosis to prevent its complications. Owing to the high rate of false negative traditional serological markers, the need for better serological testing remains.

Objective

To investigate the clinical significance of three recently discovered novel autoantibodies, anti-salivary gland protein 1 (SP1), anti-carbonic anhydrase 6 (CA6), and anti-parotid secretory protein (PSP), in a cohort of dry eye patients with suspected underlying inflammatory/autoimmune disease.

Methods

Medical records of 136 patients with a primary diagnosis of dry eye who underwent laboratory testing between April 2014 and July 2017 were reviewed retrospectively. Data regarding demographic information, ocular and systemic symptoms, previous medical diagnoses, serological test results, and minor salivary gland biopsy results were collected. Dry eye evaluations included tear osmolarity, Schirmer test without anesthesia, conjunctival lissamine green staining, and corneal fluorescein staining in the order listed here.

Results

Of the 136 patients, 9 (9/136, 6.6%) presented with a history of SS, and 9 additional patients (9/127, 7%) received a new diagnosis of SS as a result of evaluations. Fifty-six patients (56/136, 41%) tested positive for at least one of the novel autoantibodies. Fifty-four percent (6/11) of patients with primary SS who underwent the novel serological testing had a positive anti-PSP. Of those, 2 (2/11, 18%) had negative traditional serology and had to undergo minor salivary gland biopsy for definitive diagnosis. Anti-CA6 was associated with increased corneal and conjunctival staining after adjusting for age, sex, and other serologic markers (HR = 1.5, 95% CI = 1.20-1.97, and p = 0.009 and HR = 1.4, 95% CI = 1.04-1.76, and p = 0.02, respectively).

Conclusions

This cross-sectional study demonstrated that anti-CA6 is seen in patients with severe aqueous-deficient dry eye. Whether these patients have an early stage of SS or a different type of autoimmune condition may be determined through longitudinal studies.

Inflammation and pericarditis: Are neutrophils actors behind the scenes?

The morbidity of acute pericarditis is increasing over time impacting on patient quality of life. Recent clinical trials focused especially on clinical aspects, with a modest interest in pathophysiological mechanisms. This narrative review, based on papers in English language obtained via PubMed up to April 2018, aims at focusing on the role of the innate immunity in pericarditis and discussing future potential therapeutic strategies impacting on disease pathophysiology. In developed countries, most cases of pericarditis are referred to as idiopathic, although etiological causes have been described, with autoreactive/lymphocytic, malignant, and infectious ones as the most frequent causes. Apart the known impairment of the adaptive immunity, recently a large body evidence indicated the central role of the innate immune system in the pathogenesis of recurrent pericarditis, starting from similarities with autoinflammatory diseases. Accordingly, the "inflammasome" has been shown to behave as an important player in pericarditis development. Similarly, the beneficial effect of colchicine in recurrent pericarditis confirms that neutrophils are important effectors as colchicine, which can block neutrophil chemotaxis, interferes with neutrophil adhesion and recruitment to injured tissues and abrogate superoxide production. Anyway, the role of the adaptive immune system in pericarditis cannot be reduced to a black or white issue as mechanisms often overlap. Therefore, we believe that more efficient therapeutic strategies have to be investigated by targeting neutrophil-derived mediators (such as metalloproteinases) and disentangling the strict interplay between neutrophils and platelets. In this view, some progress has been done by using the recombinant human interleukin-1 receptor antagonist anakinra.

Recurrent pericarditis: still idiopathic? The pros and cons of a well-honoured term

In developed countries, more than 80% of cases of acute pericarditis remain without an established diagnosis after a conventional and standard diagnostic approach. These cases are generally labelled as 'idiopathic', i.e. without a known cause. This lack of information is a matter of concern for both patients and clinicians. Some years ago, this term reflected the state of the art of scientific knowledge on the topic. Advances have changed this point of view, in light of available molecular techniques like polymerase chain reaction able to identify viral cardiotropic agents in pericardial fluid and biopsies. Furthermore, the remarkable efficacy of interleukin-1 antagonists, a therapy targeting the innate immune response, suggests clinical and pathogenic similarity between a proportion of patients with idiopathic recurrent pericarditis and classical autoinflammatory diseases. So, it seems useful to discuss the pros and cons of using the term "idiopathic" in light of the new knowledge.

Pathogenesis of Pediatric Rheumatologic Diseases

The pathogenesis of pediatric rheumatologic conditions varies with the specific disorder; however, certain commonalities are seen: altered migration of cells into tissues, production of inflammatory mediators, and enhanced activation of cells. Autoantibodies signal loss of tolerance and B and T cells may be seen on pathologic evaluation. Neutrophils are commonly observed in tissues for many diseases and are recruited through the activation of endothelial cells. These cellular infiltrates define the inflammatory response character and in some cases provide a therapeutic framework. Increased knowledge of the interactions of these cells and their products allow targeted treatments for rheumatic diseases.

Autoimmunity in uveitis

PURPOSE

Recent insights into the pathogenesis of immune-mediated diseases proposed a new classification, which includes autoimmune and auto-inflammatory diseases. The prevalence of specific autoimmune and auto-inflammatory diseases in uveitis and/or scleritis is not yet known. In this study, we examine the presence of systemic immune-mediated diseases in patients with uveitis and/or scleritis and put a special emphasis on autoimmune disorders by reporting on their clinical manifestations and visual prognosis.

METHODS

In this retrospective study, we reviewed data of 1327 patients presenting with uveitis and/or scleritis between January 2010 and July 2016 at the Erasmus Medical Center, Rotterdam, the Netherlands. All patients with noninfectious uveitis and/or scleritis were classified according to novel criteria for immune-mediated diseases. Various clinical data, including visual acuity (VA), of patients with uveitis of autoimmune origin were registered during 5-year follow-up.

RESULTS

The origin of uveitis was in 5% (62/1327) autoimmune, in 15% (197/1327) auto-inflammatory and in 14% (180/1327) mixed autoimmune/auto-inflammatory. Patients with classical autoimmune connective tissue disease (N = 17) suffered mostly from rheumatoid arthritis and granulomatosis with polyangiitis and exhibited predominantly scleritis (53%). After 5 years of follow-up, none of the eyes of these patients developed legal blindness (VA of <0.1). The VA in patients with uveitis associated with autoimmune neuro-ophthalmological diseases (multiple sclerosis and neuromyelitis optica; N = 27) remained stable over time.

CONCLUSION

Uveitis and scleritis of autoimmune origin were observed in 5% of the total series. The term autoimmune uveitis should not be used as a synonym for intraocular inflammation of noninfectious origin.

Obesity-Related Asthma: Immune Regulation and Potential Targeted Therapies

Obesity, one of the most severe public health problems of the 21st century, is a common metabolic syndrome due to excess body fat. The incidence and severity of obesity-related asthma have undergone a dramatic increase. Because obesity-related asthma is poorly controlled using conventional therapies, alternative and complementary therapies are urgently needed. Lipid metabolism may be abnormal in obesity-related asthma, and immune modulation therapies need to be investigated. Herein, we describe the immune regulators of lipid metabolism in obesity as well as the interplay of obesity and asthma. These lay the foundations for targeted therapies in terms of direct and indirect immune regulators of lipid metabolism, which ultimately help provide effective control of obesity-related asthma with a feasible treatment strategy.

Screen-detected gallstone disease and autoimmune diseases - A cohort study

BACKGROUND

Gallstone disease is highly prevalent and is associated with systemic inflammation.

AIMS

To determine whether screen-detected gallstones or cholecystectomy are associated with the occurrence of autoimmune and autoinflammatory diseases and the most common subgroups thereof.

METHODS

A cohort study of three randomly selected general population samples from Copenhagen was performed. Participants (n = 5928) were examined in the period 1982-1992, underwent abdominal ultrasound examination to detect gallstone disease, and followed through national registers until December 2014 (median 24.7 years) for occurrence of immunological diseases. Multivariable Cox regression analyses were performed.

RESULTS

Gallstone disease was identified in 10% (591/5928) of participants, of whom 6.8% had gallstones and 3.2% had cholecystectomy at baseline. Gallstone disease was associated with incidence of autoimmune diseases (12.9% versus 7.92%; hazard ratio 1.46; 95% confidence interval [CI], [1.11;1.91]), diabetes mellitus type 1 (5.95% versus 3.67%; 1.53; [1.02;2.30]), and autoimmune thyroid disease (3.70% versus 1.59%; 2.06; [1.26;3.38]). Rheumatoid arthritis, autoinflammatory diseases, or any subgroups thereof were not associated.

CONCLUSIONS

In a large general population sample, screen-detected gallstone disease was associated with the development of autoimmune diseases during long-term follow-up. Future research efforts are needed to further explore common disease mechanisms.