Autoinflammatory diseases: clinical and genetic advances

The Neutrophilic Dermatoses, or the Cutaneous Expressions of Neutrophilic Inflammation

Acute febrile neutrophilic dermatosis, or Sweet syndrome, has been described in 1964 and is now considered as a prototypical condition of the group of the neutrophilic dermatoses. Since this time, many clinical conditions have been included in this group and a clinical-pathological classification in 3 subgroups has been proposed. Neutrophilic infiltrates can localize in all internal organs. This defines the neutrophilic disease, which induces difficult diagnostic and therapeutic problems. Autoinflammation is the main pathophysiological mechanism of the neutrophilic dermatoses. There is a special link between myeloid malignancies (leukemia and myelodysplasia) and the neutrophilic dermatoses.

microRNA-148 is involved in NF-κB signaling pathway regulation after LPS stimulation by targeting IL-1β in miiuy croaker

The inflammatory response is a protective process to clear detrimental stimuli, constitutes the defense against infectious pathogens. Clearing pathogen infection requires appropriate immune and inflammatory response, but excessive inflammatory response can lead to uncontrolled inflammation, autoimmune disease, or pathogen transmission. Accumulating evidences show that miRNAs are important and multifunctional regulators of innate immunity and inflammation. However, in the inflammatory response of lower vertebrates, the miRNAs regulatory networks are largely unknown. In this study, a combination of bioinformatics and experimental techniques were used to investigate the functions of miR-148. IL-1β is a hypothetical target gene of miR-148 predicted by bioinformatics. In addition, dual-luciferase reporter gene experiment was used to verify the targeting effect of miR-148 on IL-1β-3'UTR. miR-148 inhibits IL-1β expression in a dose-dependent manner at protein and mRNA levels. It is important that miR-148 participates in regulation of LPS-induced the NF-κB signaling pathway by inhibiting IL-1β. These results will improve our understanding of the regulation of miRNAs in fish on the immune response.

Cascade of immune mechanism and consequences of inflammatory disorders

Inflammatory responses arise as an outcome of tissues or organs exposure towards harmful stimuli like injury, toxic chemicals or pathogenic microorganism. It is a complex cascade of immune mechanism to overcome from tissue injury and to initiate the healing process by recruiting various immune cells, chemical mediators such as the vasoactive peptides and amines, pro-inflammatory cytokines, eicosanoids and acute-phase proteins to prevent tissue damage and ultimately complete restoration of the tissue function. The cytokines exhibits a central function in communication between the cells, inflammatory response initiation, amplification and their regulation. This review covers the importance of inflammatory responses; the significance of cytokines in inflammation and numerous inflammatory disorders/ailments due to the abrupt expression of cytokines and the hyper-inflammatory response or cytokine storm associated with poor prognosis in COVID-19 pandemic. Also highlighting the importance of naturally derived anti-inflammatory metabolites to overcome the side-effects of currently prevailing anti-inflammatory drugs.

Varicocele-Mediated Male Infertility: From the Perspective of Testicular Immunity and Inflammation

Background

Varicocele (VC) is present in 35 - 40% of men with infertility. However, current surgical and antioxidant treatments are not completely effective. In addition to oxidative stress, it is likely that other factors such as testicular immune microenvironment disorder contribute to irreversible testicular. Evidence suggests that VC is associated with anti-sperm antibodies (ASAs), spermatogenesis and testosterone secretion abnormalities, and testicular cytokine production. Moreover, inhibition of inflammation can alleviate VC-mediated pathogenesis. The normal function of the testis depends on its immune tolerance mechanism. Testicular immune regulation is complex, and many infectious or non-infectious diseases may damage this precision system.

Results

The testicular immune microenvironment is composed of common immune cells and other cells involved in testicular immunity. The former includes testicular macrophages, T cells, dendritic cells (DCs), and mast cells, whereas the latter include Leydig cells and Sertoli cells (SCs). In animal models and in patients with VC, most studies have revealed an abnormal increase in the levels of ASAs and pro-inflammatory cytokines such as interleukin (IL)-1 and tumor necrosis factor (TNF)-alpha in the seminal plasma, testicular tissue, and even peripheral blood. It is also involved in the activation of potential inflammatory pathways, such as the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing (NLRP)-3 pathway. Finally, the development of VC-mediated infertility (VMI) may be facilitated by abnormal permeability of proteins, such as claudin-11, that constitute the blood-testis barrier (BTB).

Conclusions

The testicular immune response, including the production of ASAs and inflammatory factors, activation of inflammatory pathways, and destruction of the BTB may be involved in the pathogenesis of VMI it is necessary to further explore how patient outcomes can be improved through immunotherapy.

Histologic Patterns and Clues to Autoinflammatory Diseases in Children: What a Cutaneous Biopsy Can Tell Us

Autoinflammation is defined by aberrant, antigen-independent activation of the innate immune signaling pathways. This leads to increased, pro-inflammatory cytokine expression and subsequent inflammation. In contrast, autoimmune and allergic diseases are antigen-directed immune responses from activation of the adaptive immune system. The innate and adaptive immune signaling pathways are closely interconnected. The group of 'complex multigenic diseases' are a result of mutual dysregulation of both the autoinflammatory and autoimmune physiologic components. In contrast, monogenic autoinflammatory syndromes (MAIS) result from single mutations and are exclusively autoinflammatory in their pathogenesis. Studying the clinical and histopathological findings for the various MAIS explains the phenotypical correlates of their specific mutations. This review aims to group the histopathologic clues for autoinflammation into three recognizable patterns. The presence of these histologic patterns in a pediatric patient with recurrent fevers and systemic inflammation should raise suspicion of an autoinflammatory component in MAIS, or, more frequently, in a complex multigenic disease. The three major histopathological patterns seen in autoinflammation are as follows: (i) the 'neutrophilic' pattern, seen in urticarial neutrophilic dermatosis, pustular psoriasis, aseptic neutrophilic folliculitis, and Sweet's syndrome; (ii) the 'vasculitic' pattern seen in small vessel-vasculitis (including hypersensitivity/leukocytoclastic vasculitis, thrombosing microangiopathy and lymphocytic vasculitis), and intermediate-sized vessel vasculitis, mimicking polyarteritis nodosa; and (iii) the 'granulomatous' pattern. Beyond these three patterns, there are additional histopathologic clues, which are detailed below. It is important for a dermatopathologist to recognize the patterns of autoinflammation, so that a diagnosis of MAIS or complex multigenic diseases may be obtained. Finally, careful histopathologic analyses could contribute to a better understanding of the various clinical manifestations of autoinflammation.

Lipopolysaccharide stimulation test on cultured PBMCs assists the discrimination of cryopyrin-associated periodic syndrome from systemic juvenile idiopathic arthritis

Systemic juvenile idiopathic arthritis (sJIA) and cryopyrin-associated periodic syndrome (CAPS) share many common manifestations. We aim to identify an applicable method to assist disease discrimination. Inflammatory cytokines were measured in the plasma of patients with CAPS, sJIA with persistent disease course and healthy controls. Supernatants collected from non-stimulated peripheral blood mononuclear cells (PBMCs) and those undergone inflammasome stimulation tests utilizing lipopolysaccharide (LPS) with and without adenosine triphosphate (ATP) were investigated. Inflammatory cytokines in patient plasma fail to differentiate sJIA from CAPS. PBMCs from sJIA secrets higher amount of IL-1β and IL-18 while CAPS PBMCs produces more caspase-1 without stimulation. IL-1β, IL-18, and caspase-1 were significantly elevated among CAPS PBMCs (all p < 0.05) upon LPS stimulation, but not when additional ATPs were provided. Levels of cytokines and PBMC responses to the stimulation assays were similar among all sJIA patients regardless of their history of macrophage activation syndrome. Unstimulated PBMC activities and the LPS inflammasome stimulation assay without exogenic ATPs can assist the differentiation of CAPS from sJIA with persistent disease course.

Pyoderma gangrenosum

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that presents with rapidly developing, painful skin ulcers hallmarked by undermined borders and peripheral erythema. Epidemiological studies indicate that the average age of PG onset is in the mid-40s, with an incidence of a few cases per million person-years. PG is often associated with a variety of other immune-mediated diseases, most commonly inflammatory bowel disease and rheumatoid arthritis. The cause of PG is not well understood, but PG is generally considered an autoinflammatory disorder. Studies have focused on the role of T cells, especially at the wound margin; these cells may support the destructive autoinflammatory response by the innate immune system. PG is difficult to diagnose as several differential diagnoses are possible; in addition to clinical examination, laboratory tests of biopsied wound tissue are required for an accurate diagnosis, and new validated diagnostic criteria will facilitate the process. Treatment of PG typically starts with fast-acting immunosuppressive drugs (corticosteroids and/or cyclosporine) to reduce inflammation followed by the addition of more slowly acting immunosuppressive drugs with superior adverse event profiles, including biologics (in particular, anti-tumour necrosis factor (TNF) agents). Appropriate wound care is also essential. Future research should focus on PG-specific outcome measures and PG quality-of-life studies.

Canakinumab Lacks Efficacy in Treating Adult Patients with Moderate to Severe Chronic Spontaneous Urticaria in a Phase II Randomized Double-Blind Placebo-Controlled Single-Center Study

BACKGROUND

Chronic idiopathic/spontaneous urticaria (CSU) is a common disease with a significant proportion of patients who do not respond to standard therapy with antihistamines and optionally corticosteroids/immunosuppressants.

OBJECTIVE

The IL-1β antagonist canakinumab is effective in cryopyrin-associated periodic syndromes associated with urticarial symptoms and urticarial vasculitis, and so it was suspected that it could also be effective in patients with CSU.

METHODS

The effect of canakinumab was investigated in 20 patients with moderate to severe CSU in a 1:1 randomization to either canakinumab or placebo in a double-blind single-dose crossover design. The verum group received 150 mg canakinumab subcutaneously once at baseline. Patients who had received placebo were able to switch to canakinumab at week 4 if they did not improve. The primary end point was clinical improvement at week 4 compared with baseline in sum of urticaria activity scores over 7 consecutive days. Secondary end points were the clinical improvement at week 8 compared with baseline in sum of urticaria activity scores over 7 consecutive days and the clinical improvement measured by the Physician Score and Dermatology Life Quality Index at week 1, 2, 4, and 8.

RESULTS

At week 4, 2 patients with canakinumab and 3 with placebo met the primary end point, and so canakinumab failed the significant superiority to the placebo (P = 1.0). An inclusion of the patients who switched to canakinumab after 4 weeks did not alter the result. There was also no significant difference between the verum and placebo groups for all secondary end points. The therapy was well tolerated, and mild adverse events were equally distributed between verum and placebo groups.

CONCLUSIONS

Because of this clinical trial with 20 patients, it must be assumed that canakinumab has no effect on lesions of CSU. This suggests that IL-1β may not play a crucial role in pathology of patients with CSU, unlike, for example, in hereditary fevers or urticarial vasculitis, where targeting IL-1 is a main treatment option. However, the good tolerability of canakinumab could be confirmed.

Second-Hit Somatic Mutations in Mevalonate Pathway Genes Underlie Porokeratosis

Familial and sporadic porokeratosis are associated with germline heterozygous mutations in mevalonate pathway genes. Kubo et al. show that each skin lesion of disseminated superficial actinic porokeratosis originates from a postnatal keratinocyte clone with a different second-hit genetic event in the wild-type allele of the corresponding gene. They also confirm that linear porokeratosis derives from a single prenatal clone of keratinocytes with a second-hit genetic event.

NLRP3 expression in mesencephalic neurons and characterization of a rare NLRP3 polymorphism associated with decreased risk of Parkinson's disease. NPJ Parkinsons Dis. 2018;4:24. [PMID: 30131971 PMCID: PMC6093937 DOI: 10.1038/s41531-018-0061-5]

Neuroinflammation is a well-characterized pathophysiology occurring in association with the progression of Parkinson's disease. Characterizing the cellular and molecular basis of neuroinflammation is critical to understanding its impact on the incidence and progression of PD and other neurologic disorders. Inflammasomes are intracellular pro-inflammatory pattern-recognition receptors capable of initiating and propagating inflammation. These cellular complexes are well characterized in the innate immune system and activity of the NLRP3 inflammasome has been reported in microglia. NLRP3 inflammasome activity has been associated with Alzheimer's disease, and recent reports, from our laboratory and others, indicate that Nlrp3 is required for neuroinflammation and nigral cell loss in animal models of PD. NLRP3 has not yet been characterized in PD patients. Here we characterize NLRP3 in PD using immunohistologic and genetic approaches. Histologic studies revealed elevated NLRP3 expression in mesencephalic neurons of PD patients. Analysis of exome sequencing data for genetic variation of NLRP3 identified multiple single-nucleotide polymorphisms (SNPs) including rs7525979 that was associated with a significantly reduced risk of developing PD. Mechanistic studies conducted in HEK293 cells indicated that the synonymous SNP, NLRP3 rs7525979, alters the efficiency of NLRP3 translation impacting NLRP3 protein stability, ubiquitination state, and solubility. These data provide evidence that dopaminergic neurons are a cell-of-origin for inflammasome activity in PD and are consistent with recent animal studies, suggesting that inflammasome activity may impact the progression of PD.

Meta-Analysis of Maternal and Fetal Transcriptomic Data Elucidates the Role of Adaptive and Innate Immunity in Preterm Birth

Preterm birth (PTB) is the leading cause of newborn deaths around the world. Spontaneous preterm birth (sPTB) accounts for two-thirds of all PTBs; however, there remains an unmet need of detecting and preventing sPTB. Although the dysregulation of the immune system has been implicated in various studies, small sizes and irreproducibility of results have limited identification of its role. Here, we present a cross-study meta-analysis to evaluate genome-wide differential gene expression signals in sPTB. A comprehensive search of the NIH genomic database for studies related to sPTB with maternal whole blood samples resulted in data from three separate studies consisting of 339 samples. After aggregating and normalizing these transcriptomic datasets and performing a meta-analysis, we identified 210 genes that were differentially expressed in sPTB relative to term birth. These genes were enriched in immune-related pathways, showing upregulation of innate immunity and downregulation of adaptive immunity in women who delivered preterm. An additional analysis found several of these differentially expressed at mid-gestation, suggesting their potential to be clinically relevant biomarkers. Furthermore, a complementary analysis identified 473 genes differentially expressed in preterm cord blood samples. However, these genes demonstrated downregulation of the innate immune system, a stark contrast to findings using maternal blood samples. These immune-related findings were further confirmed by cell deconvolution as well as upstream transcription and cytokine regulation analyses. Overall, this study identified a strong immune signature related to sPTB as well as several potential biomarkers that could be translated to clinical use.

Research of differential expression of sIL1RAP in low-grade gliomas between children and adults

Glioma is the most common intracranial malignant tumor. Low-grade gliomas (LGG) occupy almost 80% in all of the gliomas. The prognosis of LGG in children is much better than in adult, however, the molecular mechanism is still unclear. In our investigation, it was first found that the level of soluble IL1RAP (sIL1RAP) was significantly higher in the LGG from children than that from adult. We also revealed that sIL1RAP could induce the apoptosis of U251. In cells with overexpression of sIL-1RAP, the cell proliferation promoted by IL-1 was significantly inhibited. These decreased tumor growth ability and better prognosis of low-grade gliomas in children patients than that in adult patients. The expression level of sIL1RAP may become one of the potential indexes for determining the prognosis of low-grade gliomas.

Characterization of IL-1β and two types of IL-1 receptors in miiuy croaker and evolution analysis of IL-1 family

Interleukin (IL)-1β is a prototypical proinflammatory cytokine that belongs to the IL-1 family. This cytokine possesses two receptor types, namely, IL-1 receptor type I (IL-1RI) and IL-1 receptor type II (IL-1RII). IL-1RI, is an IL-1 receptor that plays a crucial role in immune responses and IL-1RII is a decoy receptor for IL-1β signaling inhibitors in mammals. IL-1β, together with its two types of receptors, has been characterized in mammals and implicated in immunity. However, IL-1β and IL-1 receptors in teleost species have been rarely investigated. In this study three genes, namely, IL-1β, IL-1RI, and IL-1RII, were identified and characterized from miiuy croaker. Structural and comparative analysis revealed that miiuy croaker IL-1β, IL-1RI and IL-1RII, particularly their functional domains, were conservative in most of the species. Simultaneously, synteny phylogenetic analysis indicated that IL-1β and IL-18 were widely distributed in vertebrates and hence might be the ancestors of the IL-1 family. Challenge experiment demonstrated that IL-1β, IL-1RI and IL-1RII expression in miiuy croaker was induced by LPS and poly (I:C). IL-1RI expression was also induced by the overexpressed miiuy croaker IL-1β protein which in cell supernatant, whereas IL-1RII was not induced.

Muckle-Wells syndrome in an Indian family associated with NLRP3 mutation

Muckle — Wells syndrome (MWS) is a rare autosomal dominant disease that belongs to a group of hereditary periodic fever syndromes. It is part of the wider spectrum of the cryopyrin-associated periodic syndrome (CAPS) which has only rarely been described in non-Caucasian individuals. It is characterized by recurrent self-limiting episodes of fever, urticaria, arthralgia, myalgia and conjunctivitis from childhood. Progressive sensorineural hearing loss and amyloidosis are two late complications. MWS is caused by gain of function mutations in the NLRP3 gene, which encodes cryopyrin, a protein involved in regulating the production of proinflammatory cytokines. We report two patients with MWS in an Indian family associated with the p.D303N mutation in the NLRP3 gene. These findings promote awareness of these hereditary periodic fever syndromes as a cause for recurrent fevers from childhood in the Indian population.

NLRP3 A439V Mutation in a Large Family with Cryopyrin-associated Periodic Syndrome: Description of Ophthalmologic Symptoms in Correlation with Other Organ Symptoms

Objective.

Cryopyrin-associated periodic syndrome (CAPS) is a group of inherited autoinflammatory disorders caused by mutations in the NLRP3 gene resulting in the overproduction of interleukin 1β. NLRP3 mutations cause a broad clinical phenotype of CAPS. The aims of the study were to evaluate clinical, laboratory, and genetic features of a 5-generation family with CAPS focusing in detail on ocular symptoms.

Methods.

In a retrospective observational cohort study, consecutive family members were screened for the presence of the NLRP3 mutation. Patients underwent standardized clinical, laboratory, and ophthalmological assessments. The genotype-specific risk of ophthalmological findings and other organ symptoms was determined.

Results.

Twenty-nine patients were clinically affected. The A439V mutation encoded by exon 3 of the NLRP3 gene was found in 15 of 37 family members (41%). The most common clinical features were musculoskeletal symptoms, headaches, and ophthalmological symptoms. The mutation-positive patients were characterized by more frequent skin rashes, ocular symptoms, arthralgia, arthritis, and severe Muckle-Wells syndrome (MWS) Disease Activity Score. Rosacea was diagnosed in 8 patients.

Conclusion.

The NLRP3 mutation A439V is associated with a heterogeneous clinical spectrum of familial cold autoinflammatory syndrome/MWS-overlap syndrome. Skin rash and eye diseases, such as conjunctivitis and uveitis, were positively correlated with this mutation.

Impact of IL-1 inhibition on fatigue associated with autoinflammatory syndromes

Cryopyrin-associated periodic syndromes (CAPS) is a rare group of autoinflammatory disorders that includes familial cold autoinflammatory syndrome or FCAS, Muckle-wells syndrome or MWS, and neonatal-onset multisystem inflammatory disease or NOMID. CAPS is caused by a mutation in the NOD-like receptor family, pyrin domain containing 3 (NLRP3) gene. This ultimately leads to increased production of interleukin (IL)-1β. IL-1β is a biologically active member of the IL-1 family. It is not only a pro-inflammatory cytokine responsible for features such as fever, rash, and arthritis, but is also a major mediator in the central pathways of fatigue. Fatigue is a major component of CAPS and is associated with severely compromised quality of life. In clinical studies, fatigue was measured using functional assessment of chronic illness therapy-fatigue or FACIT-F and short form-36 or SF-36, physical component score instruments. These questionnaires can also be used to monitor improvement of fatigue following initiation of therapy. IL-1 inhibitors block the IL-1 signaling cascade, thereby preventing systemic inflammation in CAPS. The decrease in systemic inflammation is accompanied by improvement in fatigue.

An unusual urticarial eruption: Familial cold autoinflammatory syndrome

This is a case of a 26-year-old Caucasian woman with a lifelong history of an episodic urticaria associated with arthralgia, precipitated by exposure to cold. She had no other significant past medical history. She reported several family members with a history of very similar episodic eruptions without definitive diagnoses. An examination showed an urticarial eruption over her limbs with no other systemic findings. A baseline full blood examination, serology and autoimmune screen were normal. A skin biopsy was consistent with urticaria, with dermal oedema and a perivascular infiltrate. Following genetic testing, she was found to be heterozygous for a mutation, p.Ala439Val in the NLRP3 gene, known to cause familial cold autoinflammatory syndrome (FCAS), which typically presents with urticaria, conjunctivitis and arthralgia, as described in this patient. FCAS is one subtype of a group of conditions known as cryopyrin-associated periodic syndromes (CAPS). CAPS are rare, autosomal dominant inherited conditions with a spectrum of phenotypes, characterised by increased interleukin-1β release with subsequent local and systemic proinflammatory and pyrogenic effects.

Successful renal transplantation in Muckle-Wells syndrome treated with anti-IL-1β-monoclonal antibody

We report the first case of a 32-year-old woman with Muckle–Wells syndrome and biopsy-proven systemic AA amyloidosis and end-stage renal disease. She was treated with canakinumab 150 mg subcutaneously every 8 weeks and underwent renal transplantation. Fourteen months after renal transplanation, the patient had no flares of Muckle–Wells syndrome and no evidence of amyloidosis in the renal transplant under an excellent graft function and therapy with canakinumab.

CAPS--pathogenesis, presentation and treatment of an autoinflammatory disease

The cryopyrin-associated periodic syndrome (CAPS) is a severity spectrum of rare diseases. CAPS comprises the three conditions previously described as familial cold autoinflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disorder (NOMID), also known as chronic infantile neurologic, cutaneous, and articular (CINCA) syndrome. The clinical phenotype of CAPS is characterized by systemic inflammation. General symptoms are fatigue and fever. Local manifestations affect multiple tissues such as skin, joints, muscles, eyes, and the central nervous system. Distinct clinical features are characteristic for each subphenotype. In FCAS, these are cold-induced urticaria and fever, in MWS systemic amyloidosis and hearing loss and in NOMID/CINCA central nervous system inflammation and bone deformities. CAPS is caused by single heterozygous germline or somatic gain of function mutations in the NLRP3 gene encoding the protein cryopyrin. Cryopyrin nucleates an NLRP3 inflammasome, which regulates the activation and cleavage of caspase-1 that cleaves the pro-inflammatory cytokines, IL-1β and IL-18. IL-1β plays the key role in the induction of inflammation in CAPS. This has been confirmed by the application of IL-1 blocking agents, which lead not only to a rapid and sustained reversal of daily symptoms but also to some extent of long-term disease sequelae. To prevent CAPS-induced organ damage, early diagnosis and swift initiation of effective treatment are mandatory.

Cytokines and chemokines: At the crossroads of cell signalling and inflammatory disease

Inflammation occurs as a result of exposure of tissues and organs to harmful stimuli such as microbial pathogens, irritants, or toxic cellular components. The primary physical manifestations of inflammation are redness, swelling, heat, pain, and loss of function to the affected area. These processes involve the major cells of the immune system, including monocytes, macrophages, neutrophils, basophils, dendritic cells, mast cells, T-cells, and B-cells. However, examination of a range of inflammatory lesions demonstrates the presence of specific leukocytes in any given lesion. That is, the inflammatory process is regulated in such a way as to ensure that the appropriate leukocytes are recruited. These events are in turn controlled by a host of extracellular molecular regulators, including members of the cytokine and chemokine families that mediate both immune cell recruitment and complex intracellular signalling control mechanisms that characterise inflammation. This review will focus on the role of the main cytokines, chemokines, and their receptors in the pathophysiology of auto-inflammatory disorders, pro-inflammatory disorders, and neurological disorders involving inflammation.

Autoinflammatory syndromes for the dermatologist

While autoimmunity as cause of disease is well-established, other categories of immune-mediated diseases that are not produced by targeting of self-antigens by antibodies is in the process of being described. These so-called autoinflammatory diseases arise when an inappropriate activation of antigen-independent mechanisms occurs. Autoinflammatory diseases course with recurrent attacks of fever and multisystemic inflammation; however, the skin may also be affected by a variety of inflammatory manifestations that often alert the clinician about the presence of an autoinflammatory disease. Recognizing the cutaneous features of these syndromes will aid for prompt diagnosis and early treatment that is key for the quality of life and survival of the affected patients. In this paper, we focus on the skin manifestations of autoinflammatory diseases in children, which is the usual period of appearing of the first symptoms and signs.

Pyoderma gangrenosum. experience of successful treatment with systemic glucocorticosteroids, azathioprine, antibiotics and phototherapy using the «PhotoDyn-750» device

The article presents the results of a clinical observation of a rare dermatosis, pyoderma gangrenosum, and results of successful complex treatment of the disease with systemic GCS, azathioprine, antibiotics and phototherapy using the «PhotoDyn-750» device.

The structural pathway of interleukin 1 (IL-1) initiated signaling reveals mechanisms of oncogenic mutations and SNPs in inflammation and cancer

Interleukin-1 (IL-1) is a large cytokine family closely related to innate immunity and inflammation. IL-1 proteins are key players in signaling pathways such as apoptosis, TLR, MAPK, NLR and NF-κB. The IL-1 pathway is also associated with cancer, and chronic inflammation increases the risk of tumor development via oncogenic mutations. Here we illustrate that the structures of interfaces between proteins in this pathway bearing the mutations may reveal how. Proteins are frequently regulated via their interactions, which can turn them ON or OFF. We show that oncogenic mutations are significantly at or adjoining interface regions, and can abolish (or enhance) the protein-protein interaction, making the protein constitutively active (or inactive, if it is a repressor). We combine known structures of protein-protein complexes and those that we have predicted for the IL-1 pathway, and integrate them with literature information. In the reconstructed pathway there are 104 interactions between proteins whose three dimensional structures are experimentally identified; only 15 have experimentally-determined structures of the interacting complexes. By predicting the protein-protein complexes throughout the pathway via the PRISM algorithm, the structural coverage increases from 15% to 71%. In silico mutagenesis and comparison of the predicted binding energies reveal the mechanisms of how oncogenic and single nucleotide polymorphism (SNP) mutations can abrogate the interactions or increase the binding affinity of the mutant to the native partner. Computational mapping of mutations on the interface of the predicted complexes may constitute a powerful strategy to explain the mechanisms of activation/inhibition. It can also help explain how an oncogenic mutation or SNP works.

Structural pathways are important because they provide insight into signaling mechanisms; help understand the mechanism of disease-related mutations; and help in drug discovery. While extremely useful, common pathway diagrams lacking structural data are unable to provide mechanistic insight to explain oncogenic mutations or SNPs. Here we focus on the construction of the IL-1 structural pathway and map oncogenic mutations and SNPs to complexes in this pathway. Our results indicate that computational modeling of protein-protein interactions on a large scale can provide accurate, structural atom-level detail of signaling pathways in the human cell and help delineate the mechanism through which a mutation leads to disease. We show that the mutations either thwart the interactions, activating the proteins even in their absence or stabilize them, leading to the same uncontrolled outcome. Computational mapping of mutations on the interface of the predicted complexes may constitute an effective strategy to explain the mechanisms of mutations- constitutive activation or deactivation.

Canakinumab in patients with cryopyrin-associated periodic syndrome: an update for clinicians

The cryopyrin-associated periodic syndrome (CAPS) is a very rare disease. It is estimated that there are 1-2 cases for every 1 million people in the US and 1 in every 360,000 in France. However, many patients are diagnosed very late or not at all, meaning the real prevalence is likely to be higher. CAPS encompasses the three entities of familial cold auto-inflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease (NOMID)/chronic infantile neurologic, cutaneous and articular (CINCA) syndrome. They have in common a causative mutation in the NLRP3 gene. The altered gene product cryopyrin leads to activation of the inflammasome which in turn is responsible for excessive production of interleukin (IL)-1β. IL-1β causes the inflammatory manifestations in CAPS. These appear as systemic inflammation including fever, headache or fatigue, rash, eye disease, progressive sensorineural hearing loss, musculoskeletal manifestations and central nervous system (CNS) symptoms (NOMID/CINCA only). With the advent of IL-1 Inhibitors, safe and effective therapeutic options became available for this devastating disease. To prevent severe and possible life-threatening disease sequelae, early and correct diagnosis and immediate initiation of therapy are mandatory in most patients. Canakinumab is a fully human monoclonal IgG1 anti-IL-1β antibody. It provides selective and prolonged IL-1β blockade and has demonstrated a rapid (within hours), complete and sustained response in most CAPS patients without any consistent pattern of side effects. Long-term follow-up trials have demonstrated sustained efficacy, safety and tolerability. Canakinumab is approved by the US Food and Drug Administration for FCAS and MWS and by European Medicines Agency for treatment of all three phenotypes of CAPS.

Molecular and functional characterization of IL-1 receptor type 2 in grass carp: a potent inhibitor of IL-1β signaling in head kidney leukocytes

IL-1 receptor type 2 (IL-1R2) is known as one of natural IL-1β singling inhibitors in mammals. However, the functional role of IL-1R2 in fish remains largely unknown. In this study, grass carp (Ctenopharyngodon idellus) IL-1R2 (gcIL-1R2) was identified and functionally characterized. Similar to its fish homologs, the deduced protein of gcIL-1R2 possessed two Ig-like domains in its extracellular region but lacked an intracellular signaling domain. The involvement of gcIL-1R2 in immune response was demonstrated by investigating its expression profiles in head kidney and head kidney leukocytes (HKLs) following in vivo bacterial infection and in vitro LPS treatment, respectively. Moreover, recombinant grass carp IL-1β (rgcIL-1β) was able to stimulate gcIL-1R2 mRNA expression with a rapid kinetics. This stimulation was possibly dependent on p38, JNK, p42/44 and NF-κB pathways in grass carp HKLs, revealing a new regulatory point of IL-1β signaling at receptor level in fish. Furthermore, recombinant protein of the gcIL-1R2 extracellular region (rgcIL-1R2) was demonstrated to interact with rgcIL-1β by using ELISA, elucidating the binding specificity of gcIL-1R2. Importantly, the stimulatory effect of rgcIL-1β on its own mRNA expression was blocked by rgcIL-1R2 in a dose-dependent manner in grass carp HKLs, providing the evidence for a functional role of IL-1R2 in IL-1β signaling in teleost. These findings suggested that teleost IL-1R2 may serve as a local naturally occurring inhibitor involving in IL-1β signaling as seen in mammals.

Muckle-Wells syndrome without mutation in exon 3 of the NLRP3 gene, identified by evidence of excessive monocyte production of functional interleukin 1β and rapid response to anakinra

We report a man with lifelong urticaria, night sweats, arthralgia and lethargy. He had high levels of inflammatory markers and serum amyloid A, but no identifiable mutation in exon 3 of the NLRP3 (NOD-like receptor family, pyrin domain-1 containing 3) gene, and no relevant family history. We found marked production of functional interleukin (IL)-1 by the patient's monocytes at baseline and after stimulation with lipopolysaccharide. The patient made an immediate response to treatment with an IL-1β receptor antagonist. We propose that this patient has Muckle-Wells syndrome without deafness, occurring de novo. Functional screening for IL-1 production could aid diagnosis in future similar cases.

Erysipelas-like erythema of familial Mediterranean fever syndrome: a case report with emphasis on histopathologic diagnostic clues

We report histopathological findings in a case of familial Mediterranean fever (FMF) syndrome with an erysipelas-like erythema (ELE). ELE is the only pathognomic cutaneous manifestation of FMF. ELE is characterized by well-demarcated, tender, erythematous and infiltrated plaques recurring on the same site and resolving spontaneously within 48-72 h. FMF is a monogenic autoinflammatory syndrome highlighted by recurrent fever associated with polyserositis involving mainly the peritoneum, synovium and pleura. FMF results from a mutation of the MEFV gene, which encodes for pyrin, leading to Il-1β activation and promoting neutrophil migration into the dermis. Histopathological findings in our case showed a sparse superficial perivascular and interstitial lymphocytic infiltrate admixed with some neutrophils, no eosinophils and mild papillary dermal edema. Venules and lymphatics were dilated, though no vasculitis was identified. Neutrophils are the most common cutaneous marker of autoinflammation, and cutaneous manifestations of monogenic autoinflammatory syndromes are represented by the spectrum of aseptic neutrophilic dermatoses. Neutrophils in the presence of recurrent fever and in the correct clinical context of recurrent erysipelas in the same site are a diagnostic clue for FMF.

Febrile conditions in rheumatology

Fever is not the most frequent symptom in rheumatology; however, its occurrence always draws attention to a severe underlying pathologic process. The rheumatologic assessment of febrile patients usually takes place for three reasons: the patient's fever is associated with known rheumatic disease or musculoskeletal symptoms, or rheumatologic cause is suggested as the underlying cause of fever of unknown origin. The primary task of the rheumatologist is to rule out infections and autoimmune processes. In addition to the musculoskeletal and accompanying symptoms, the information about the course of fever and the observation of the continuity or periodicity of fever provide help to establish the diagnosis. A summarising discourse about this issue is rarely published in this speciality; therefore, we found it important to provide an overview of rheumatological diseases accompanied by fever.

[Cryopyrin-associated periodic syndrome]

The cryopyrin-associated periodic syndrome is a very rare disease. It is estimated that there are 1-2 cases out of 1 million inhabitants in the USA and 1/360,000 in France. However, many patients are diagnosed very late or not at all. Therefore the real prevalence is likely to be higher. CAPS encompasses the three entities familial cold autoinflammatory syndrome (FCAS), the Muckle-Wells syndrome and the neonatal-onset multisystem inflammatory disease (NOMID)/chronic infantile neurologic cutaneous and articular (CINCA) syndrome. They have in common a causative mutation in the NLRP3-gene. The altered gene product cryopyrin leads to activation of the inflammasome which in turn is responsible for excessive production of IL-1β. IL-1β causes the inflammatory manifestations in CAPS. These appear as systemic inflammation including fever, headache or fatigue, rash, eye disease, progressive sensorineural hearing loss, musculoskeletal manifestations and CNS symptoms (NOMID/CINCA only). With the advent of the IL-1 inhibitors anakinra, rilonacept and canakinumab for the first time safe and effective therapeutic options are available for this devastating disease. To prevent severe and possible life-threatening disease sequelae, early and correct diagnosis and immediate initiation of therapy are mandatory.

Fatal myocarditis in a child with systemic onset juvenile idiopathic arthritis during treatment with an interleukin 1 receptor antagonist

BACKGROUND

The pathologic diagnosis of isolated myocarditis without pericardial involvement is uncommonly encountered in systemic onset Juvenile Idiopathic Arthritis (soJIA).

CASE

An eleven year-old boy with soJIA died suddenly while being treated with the interleukin 1 (IL-1) receptor inhibitor, anakinra. His autopsy revealed an enlarged heart and microscopic findings were consistent with myocarditis, but not pericarditis. Viral PCR testing performed on his myocardial tissue was negative.

CONCLUSION

This case illustrates myocarditis as a fatal complication of soJIA, potentially enabled by anakinra.

[Pattern recognition receptors]

Immunity is based on self/nonself discrimination. In vertebrates, two major systems, innate and adaptive immune systems, constitute host defense against invading microbes. Adaptive immunity is characterized by specific immune responses through B- or T-cell antigen receptors that are generated by somatic recombination, whereas nonspecific responses to microbes had been accentuated in innate immunity. However, the discovery of pattern recognition receptors (PRRs) that are encoded in the germ-line, including Toll-like receptors, RIG-I-like receptors, NOD-like receptors and AIM2-like receptors, advanced our understanding of a mechanism for innate immune recognition. These types of PRR recognize pathogen- or damage-associated molecular patterns (PAMPs or DAMPs) during infection or tissue damage, and commonly evoke the downstream gene induction programme, such as expression of type I interferons, inflammatory cytokines and chemokines. Dysregulation of PRR-triggered signal activation leads to pathologic inflammatory responses. In this regard, it has been shown that many of "autoinflammatory diseases", recently defined clinical entity, have putatively causative mutations in the genes that encode PRRs or their signaling mediators. In this review article, we describe recent overview of PRRs as innate sensors and update knowledge of "autoinflammatory diseases" particularly by focusing on their association with innate signaling.

[Autoinflammatory diseases as cause of wound healing defects]

Ulcerations of the skin and mucosal membranes are a common feature of autoinflammatory diseases. They can give raise to chronic wound healing defects and should be considered in the differential diagnosis of chronic skin ulcers. The increased activation of the innate immune system in the absence of an apparent provocation for inflammation is a hallmark of autoinflammatory diseases. Mutations and alterations of signaling pathways regulating the innate immune response to physical trauma/tissue damage result into an unrestrained activation of the inflammasome, which leads to increased activation of Interleukin-1. Uncontrolled recruitment and activation of myeloid effector cells within the wound site lead to the release of potent proteases that cause the degradation of structural components of the skin. The majority of these diseases respond well to immunosuppressive and immunomodulatory treatment regimes. Therapeutic resistance converts the acute inflammatory response into a chronic and non-resolving inflammatory process that leads to tissue degeneration. In this article we will focus on the review of those autoinflammatory diseases that often display ulcerative cutaneous and aphthous lesions including pyoderma gangrenosum, Behçet disease, PAPA syndrome and hyperimmunoglobulinemia D with periodic fever syndrome (HIDS). Furthermore, the article will be complemented by an overview of those inflammatory diseases that are associated with non-ulcerative cutaneous manifestations.

Sustained remission of symptoms and improved health-related quality of life in patients with cryopyrin-associated periodic syndrome treated with canakinumab: results of a double-blind placebo-controlled randomized withdrawal study

Abstract

Trial registration

Clintrials.gov NCT00465985

Four cases of Muckle-Wells syndrome within the same family

Muckle-Wells syndrome is a rare autosomal dominant disease that belongs to a group of hereditary febrile syndromes. It is characterized by recurrent and self-limited episodes of fever, urticaria, arthralgia, myalgia and conjunctivitis since childhood, which are related to exposure to cold temperatures. Lately, progressive sensorineural hearing loss occurs. Amyloidosis is the main complication and can be found in about 25% of the cases. It has been demonstrated that there is an association with mutations in the NLRP3 gene, which codifies cryopyrin, a protein responsible for regulating the production of proinflammatory cytokines, such as interleukin-1Beta. The authors report four cases of the disease within a family.

Periodic fever syndrome with relapsing glomerulonephritis: a case report and teaching points

We report a case of relapsing mesangial and endocapillary proliferative glomerulonephritis (GN) associated with a periodic fever syndrome. The patient presented 11 times in >4 years with acute febrile episode followed in 1–3 days by hematuria, thrombocytopenia and other symptoms of acute GN with variable severity of acute kidney injury. In three episodes, the patient required renal replacement therapy for 7, 10 and 2 treatments, respectively. Shortly after the acute symptoms of the febrile episode had resolved each time, the kidney function would recover and the serum creatinine would return to baseline. Two kidney biopsies obtained during separate episodes showed acute tubular injury along with morphological changes resembling post-infectious GN but with no clinical evidence to support an infectious etiology. Multiple treatment regimens were unable to control the disease. Symptoms were alleviated by rituximab but did not completely remit. Stable remission of the periodic fever and GN was finally achieved after anakinra therapy was initiated 18 months ago. Since then, the patient had several episodes of documented infection without high fever and nephritic kidney manifestations. His kidney function remained stable with normal serum creatinine.