Anti-PSTPIP1 (aa 88-118) polyclonal antibody

BACKGROUND: Monogenic autoinflammatory diseases are caused by pathogenic variants in genes that regulate innate immune responses, and are characterized by sterile systemic inflammatory episodes. Since symptoms can overlap within this rapidly expanding disease category, accurate genetic diagnosis is of the utmost importance to initiate early inflammation-targeted treatment and prevent clinically significant or life-threatening complications. Initial recommendations for the genetic diagnosis of autoinflammatory diseases were limited to a gene-by-gene diagnosis strategy based on the Sanger method, and restricted to the 4 prototypic recurrent fevers (MEFV, MVK, TNFRSFJA, and NLRP3 genes). The development of best practices guidelines integrating critical recent discoveries has become essential. METHODS: The preparatory steps included 2 online surveys and pathogenicity annotation of newly recommended genes. The current guidelines were drafted by European Molecular Genetics Quality Network members, then discussed by a panel of experts of the International Society for Systemic Autoinflammatory Diseases during a consensus meeting. RESULTS: In these guidelines, we combine the diagnostic strength of next-generation sequencing and recommendations to 4 more recently identified genes (ADA2, NOD2, PSTPIP1, and TNFAIP3), nonclassical pathogenic genetic alterations, and atypical phenotypes. We present a referral-based decision tree for test scope and method (Sanger versus next-generation sequencing) and recommend on complementary explorations for mosaicism, copy-number variants, and gene dose. A genotype table based on the 5-category variant pathogenicity classification provides the clinical significance of prototypic genotypes per gene and disease. CONCLUSIONS: These guidelines will orient and assist geneticists and health practitioners in providing up-to-date and appropriate diagnosis to their patients.

BackgroundAutosomal dominant gain of function mutations in caspase recruitment domain family member 14 (CARD14) is a rare condition associated with plaque-type psoriasis, generalized pustular psoriasis, palmoplantarpustular psoriasisand pityriasisrubrapilaris. Recently, a new CARD14 -associated phenotype defined as CAPE (CARD14-associated papulosquamous eruption) with clinical features of both psoriasis and pityriasisrubrapilaris was reported. We describe a family carrying a novel heterozygous mutation in CARD14 gene, with childhood-onset erythrodermic psoriasis requiring an unusual extremely high dose (up to 2mg/kg every 8weeks) of ustekinumab to achieve disease remission.Case presentationWe describe a large family with three pairs of twins presenting a clinical phenotype characterized by childhood-onset erythrodermic psoriasis; in some family members is also reported psoriatic arthritis. The two probands presented poor clinical response to topic and systemic therapy with antihistamine, steroid, retinoids, cyclosporine and etanercept. After exclusion of the most common genes associated to autoinflammatory diseases (IL36RN, IL1RN, MVK, TNFRSF1A, NLRP3, NLRP12, MEFV, NOD2, PSMB8, PSTPIP1, LPIN2) we approached a new gene search by subjecting to Whole Exome Sequencing (WES) analysis five members of the family. A novel heterozygous mutation (c.446T>G, leading to the missense amino acid substitution p.L149R) in the exon 4 of the CARD14 gene was identified in all affected members. Increasing dosages (up to 2mg/kg every 8weeks) of ustekinumab, a human monoclonal antibody targeting interleukin-12 (IL-12) and interleukin-23 (IL-23), allowed the complete control of the clinical manifestations, with an evident reduction of circulating Th17 and Th22 CD4+ T cell subsets.ConclusionsWe describe the association of mutations of the CARD14 gene with an erythrodermic psoriasis pedigree, underlying the necessity to investigate CARD14 mutations in childhood-onset psoriasis cases and confirming the presence of CARD14 causative mutations also in erythrodermic psoriasis form, as recently reported. Also in pediatric age, ustekinumab represents a powerful therapeutic option for this rare condition, that is usually refractory to other treatments. In young children, high and frequent dosages allowed a complete control of the clinical manifestations without any severe side effects, with a long-term follow-up.