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Pyrin responds to pathogen signals and loss of cellular homeostasis by forming an inflammasome complex that drives the cleavage and secretion of IL-1β. We studied a family with dominantly inherited autoinflammatory disease characterised by childhood-onset recurrent episodes of neutrophilic dermatosis, fever, elevated acute-phase reactants, arthralgia, and myalgia/myositis. Disease was caused by a mutation in MEFV, the gene encoding pyrin (S242R). The clinical distinction from FMF, also caused by MEFV mutation, was due to loss of a 14-3-3 binding motif at phosphorylated S242. This interaction represents a guard regulating pyrin activation, which is downstream of bacterial effectors that trigger the pyrin inflammasome. S242R mutation recapitulated the effect of pathogen sensing, triggering inflammasome activation and IL-1β production. Successful therapy targeting IL-1β has been initiated in one patient, resolving Pyrin-Associated Autoinflammation with Neutrophilic Dermatosis (PAAND). This unique disease provides evidence that a guard mechanism, originally identified in plant innate immunity, also exists in humans.3 Main textAutoinflammatory diseases are characterized by recurrent episodes of fever with systemic and organ-specific inflammation, as well as uncontrolled activation of the innate immune response in the apparent absence of an infectious trigger(1). Familial Mediterranean fever (FMF, OMIM ID: 249100) is the most common of these monogenic diseases, characterized by short (24-72 h) episodes of fever associated with serositis, progressing to amyloidosis if untreated(2). FMF is an autosomal recessive disease caused by mutations in both alleles of the MEFV (MEditerranean FeVer) locus, which encodes the protein pyrin(3). Normally, pyrin functions as a link between intracellular pathogen sensing and activation of the inflammasome, allowing the production of inflammatory mediators during infection. As a potent checkpoint for the initiation of inflammation, the mechanisms of pyrin regulation are critical, and yet still poorly understood.We studied a three-generation Belgian family of 22 individuals, of whom 12 developed autoinflammatory disease (Figure 1a). The disease was characterized by neutrophilic dermatosis, childhood-onset recurrent episodes of fever lasting several weeks, increased levels of acute-phase reactants, arthralgia and myalgia/myositis (Figure 1b). The neutrophilic dermatosis comprised a spectrum of clinical manifestations including severe acne, sterile skin abscesses, pyoderma gangrenosum and neutrophilic small vessel vasculitis (Figure 1c,d).Pathological examination of affected skin showed a dense, predominantly neutrophilic, vascular, perivascular and interstitial infiltrate (Figure 1d). Serum cytokine analysis revealed elevated inflammatory mediators such as IL-1β, IL-6 and TNFα, and cytokines induced by inflammation such as IL-1Ra (Figure 1e, Figure S1a unlike some of the more typical FMF variants, that naturally occur in other species(7). Despite the association of MEFV mutations w...

Our results provide the basis for a detailed prospective evaluation of autoimmunity and inflammation in the context of PIDs, with a view to accurately assessing these risks and describing the possible effect of medical intervention.

BackgroundThe Hygiene Hypothesis (HH) attributes the dramatic increase in autoimmune and allergic diseases observed in recent decades in Western countries to the reduced exposure to diverse immunoregulatory infectious agents. This theory has since largely been supported by strong epidemiological and experimental evidence.DiscussionThe analysis of these data along with the evolution of the Western world’s microbiome enable us to obtain greater insight into microorganisms involved in the HH, as well as their regulatory mechanisms on the immune system. Helminthes and their derivatives were shown to have a protective role. Helminthes’ broad immunomodulatory properties have already begun to be exploited in clinical trials of autoimmune diseases, including inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, and type-1 diabetes.SummaryIn this review, we will dissect the microbial actors thought to be involved in the HH as well as their immunomodulatory mechanisms as emphasized by experimental studies, with a particular attention on parasites. Thereafter, we will review the early clinical trials using helminthes’ derivatives focusing on autoimmune diseases.

ClinicalTrials.gov: NCT01034969.

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This study describes the efficacy of biologics for refractory RP. However, the number of complete responses was low and there were concerns about the risk of ADRs, particularly infections.

Although splenectomy is still considered the most effective curative treatment for immune thrombocytopenia (ITP), its use has significantly declined in the last decade, especially since the approval of thrombopoietin receptor agonists (TPO-RAs).The main objective of the study was to determine whether splenectomy was still as effective nowadays, particularly for patients with failure to respond to TPO-RAs.Our secondary objective was to assess, among patients who relapsed after