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Autoinflammatory Disorder (autoinflammatory + disorder)
Selected AbstractsMutational spectrum and genotype,phenotype correlations in mevalonate kinase deficiency,HUMAN MUTATION, Issue 8 2006Saskia H.L. Mandey Abstract Mevalonate kinase deficiency (MKD) is an autosomal recessive autoinflammatory disorder caused by mutations in the MVK gene resulting in deficient activity of mevalonate kinase (MK). Depending on the clinical severity, MKD may present as hyper-IgD and periodic fever syndrome (HIDS) or the more severe mevalonic aciduria (MA). We analyzed the MVK gene in 57 patients with MKD and found 39 different mutations including 15 novel mutations, expanding the total mutational spectrum of MKD to 63 mutations. To get more insight into the genotype,phenotype correlation in MKD, we studied the effect of selected missense mutations on MK protein stability and activity in various patient fibroblast cell lines. All MKD cell lines showed markedly decreased MK activities that correlated well with the clinical severity and, for most of the cell lines, with the amount of MK protein. When fibroblasts of MKD patients were cultured under conditions known to promote a more controlled protein folding, all cell lines of patients with the HIDS phenotype and few cell lines of patients with the MA phenotype showed an increase in the residual MK activity. This increase in enzyme activity correlates well with an increase in the MK protein levels in these cell lines, indicating that most of the mutations in MKD affect stability and/or folding of the MK protein rather than affecting the catalytic properties of the enzyme. The finding that the residual activity in MKD can be manipulated by environmental conditions may offer therapeutic options to alleviate or prevent the clinical symptoms associated with MKD. Hum Mutat 27(8), 796,802, 2006. © 2006 Wiley-Liss, Inc. [source] The Schnitzler syndrome: Chronic urticaria and monoclonal gammopathy , an autoinflammatory syndrome?JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 8 2008Elisabeth Eiling Summary Schnitzler syndrome describes the simultaneous occurrence of monoclonal gammopathy and chronic urticaria with at least two additional minor symptoms (arthralgia, bone pain, fever of uncertain origin, hepato- or splenomegaly, lymphadenopathy, increased erythrocyte sedimentation rate, leukocytosis/thrombocytosis or increased bone density). Schnitzler syndrome is not wellknown and very likely under-recognized. Comprehensive diagnostic examinations are necessary to rule out other diseases, especially those of hematologic origin. Close interdisciplinary collaboration is mandatory. The etiology of Schnitzler syndrome is unclear, but the rapid response to the interleukin-1 receptor inhibitor anakinra underlines the pivotal role which the proinflammatory cytokine interleukin-1 may play in the pathophysiology of this potentially autoinflammatory disorder. [source] Intra-abdominal abscess in a patient with tumour necrosis factor receptor-associated periodic syndromeJOURNAL OF INTERNAL MEDICINE, Issue 2 2006S. STJERNBERG-SALMELA Abstract. Tumour necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is an autoinflammatory disorder characterized by periodic attacks of fever and inflammation, due to mutations in the gene coding for the TNF type I receptor (TNFRSF1A). A 16-year-old patient with the diagnosis of TRAPS was admitted to hospital because of fever and abdominal pain. Initially, the symptoms were interpreted as manifestations of another TRAPS attack, but the patient's condition worsened, despite treatment with corticosteroids and antibiotics. A repeated computer tomography revealed an intra-abdominal abscess, which necessitated urgent surgical intervention. This case stresses the importance of differential diagnostic vigilance when dealing with patients with rare genetic diseases. [source] Functional consequences of a germline mutation in the leucine-rich repeat domain of NLRP3 identified in an atypical autoinflammatory disorderARTHRITIS & RHEUMATISM, Issue 4 2010Isabelle Jéru Objective To gain insight into the pathophysiology of an atypical familial form of an autoinflammatory disorder, characterized by autosomal-dominant sensorineural hearing loss, systemic inflammation, increased secretion of interleukin-1, (IL-1,), and the absence of any cutaneous manifestations, and to assess the functional consequences of a missense mutation identified in the leucine-rich repeat (LRR) domain of NLRP3. Methods Microsatellite markers were used to test the familial segregation of the NLRP3 locus with the disease phenotype. All NLRP3 exons were screened for mutations by sequencing. Functional assays were performed in HEK 293T cells to determine the effects of mutated (versus normal) NLRP3 proteins on NF-,B activation, caspase 1 signaling, and speck formation. Results A heterozygous NLRP3 missense mutation (p.Tyr859Cys) was identified in exon 6, which encodes the LRR domain of the protein. This mutation was found to segregate with the disease phenotype within the family, and had a moderate activating effect on speck formation and procaspase 1 processing and did not alter the inhibitory properties of NLRP3 on NF-,B signaling. Conclusion This report is the first to describe a familial form of a cryopyrinopathy associated with a mutation outside of exon 3 of NLRP3. This finding, together with the known efficacy of anti,IL-1 treatments in these disorders, underlines the importance of screening all exons of NLRP3 in patients who present with atypical manifestations. In addition, the gain of function associated with this mutation in terms of activation of caspase 1 signaling was consistent with the observed inflammatory phenotype. Therefore, this study of the functional consequences of an LRR mutation sheds new light on the clinical relevance of in vitro assays. [source] The NOD2 defect in Blau syndrome does not result in excess interleukin-1 activityARTHRITIS & RHEUMATISM, Issue 2 2009Tammy M. Martin Objective Blau syndrome is a rare, autosomal-dominant, autoinflammatory disorder characterized by granulomatous arthritis, uveitis, and dermatitis. Genetics studies have shown that the disease is caused by single nonsynonymous substitutions in NOD-2, a member of the NOD-like receptor or NACHT,leucine-rich repeat (NLR) family of intracellular proteins. Several NLRs function in the innate immune system as sensors of pathogen components and participate in immune-mediated cellular responses via the caspase 1 inflammasome. Mutations in a gene related to NOD-2, NLRP3, are responsible for excess caspase 1,dependent interleukin-1, (IL-1,) in cryopyrinopathies such as Muckle-Wells syndrome. Furthermore, functional studies demonstrate that caspase 1,mediated release of IL-1, also involves NOD-2. The aim of this study was to test the hypothesis that IL-1, may mediate the inflammation seen in patients with Blau syndrome. Methods IL-1, release was measured in peripheral blood mononuclear cells cultured in vitro, obtained from 5 Blau syndrome individuals with a NOD2 (CARD15) mutation. Results We observed no evidence for increased IL-1, production in cells obtained from subjects with Blau syndrome compared with healthy control subjects. Furthermore, we presented 2 cases of Blau syndrome in which recombinant human IL-1 receptor antagonist (anakinra) was ineffective treatment. Conclusion Taken together, these data suggest that in contrast to related IL-1,,dependent autoinflammatory cryopyrinopathies, Blau syndrome is not mediated by excess IL-1, or other IL-1 activity. [source] |