We report three cases of pulmonary disease suggesting fibrosis in two familial and one sporadic case. Pulmonary symptoms were associated with various clinical features of systemic inflammation and ...vasculitis involving the skin, and appeared at different ages. A strong interferon signature was found in all three cases. Disease was not responsive to corticosteroids, and lung transplantation was considered for all three subjects at an early age. One of them underwent double-lung transplantation, but she immediately experienced a primary graft dysfunction and died soon after. Recognized causes of familial interstitial lung disease were all excluded. All three subjects had a mutation in the previously described autoinflammatory disease called SAVI (stimulator of interferon genes STING-associated vasculopathy with onset in infancy). These cases emphasize the need to consider this possibility in children and young adults with lung fibrosis after common causes have been ruled out.
The patients, aged between 5 and 12 years, exhibited the phenotypic variability associated with TMEM173-activating mutations,2-4 with lung disease and systemic inflammation being the major features ...in patient 1 (P1) and patient 3 (P3), while in patient 2 (P2) skin involvement was most prominent (Fig 1; see Supplemental Text and Table E1 in this article's Online Repository at www.jacionline.org). Modest and incomplete downregulation of ISG was recently described in splenic B cells of mice treated with tofacitinib, a JAK1/3 inhibitor, with differential signaling effects suggesting currently poorly understood facets of IFN regulation.9 In this regard, our kinetic ex vivo experiments provide insights into the rapid dynamic changes in IFN signaling secondary to JAK1 blockade.
Background PRKDC encodes for DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a kinase that forms part of a complex (DNA-dependent protein kinase DNA-PK) crucial for DNA double-strand break ...repair and V(D)J recombination. In mice DNA-PK also interacts with the transcription factor autoimmune regulator (AIRE) to promote central T-cell tolerance. Objective We sought to understand the causes of an inflammatory disease with granuloma and autoimmunity associated with decreasing T- and B-cell counts over time that had been diagnosed in 2 unrelated patients. Methods Genetic, molecular, and functional analyses were performed to characterize an inflammatory disease evocative of a combined immunodeficiency. Results We identified PRKDC mutations in both patients. These patients exhibited a defect in DNA double-strand break repair and V(D)J recombination. Whole-blood mRNA analysis revealed a strong interferon signature. On activation, memory T cells displayed a skewed cytokine response typical of TH 2 and TH 1 but not TH 17. Moreover, mutated DNA-PKcs did not promote AIRE-dependent transcription of peripheral tissue antigens in vitro . The latter defect correlated in vivo with production of anti–calcium-sensing receptor autoantibodies, which are typically found in AIRE-deficient patients. In addition, 9 months after bone marrow transplantation, patient 1 had Hashimoto thyroiditis, suggesting that organ-specific autoimmunity might be linked to nonhematopoietic cells, such as AIRE-expressing thymic epithelial cells. Conclusion Deficiency of DNA-PKcs, a key AIRE partner, can present as an inflammatory disease with organ-specific autoimmunity, suggesting a role for DNA-PKcs in regulating autoimmune responses and maintaining AIRE-dependent tolerance in human subjects.
Upon microbial phagocytosis, neutrophils use at least 2 major and well-established intracellular killing mechanisms, that is, the production of reactive oxygen species (ROS) by the phagocyte ...nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system, and the release of antimicrobial components from intracellular granules.1 Protein kinase C delta (PKCδ) is a serine and threonine kinase and a member of the so-called novel PKC isoenzyme family.2 PKCδ is expressed in neutrophils3 and can mediate the phosphorylation of the p47phox subunit of NADPH oxidase, suggesting a regulatory function in ROS production.4 However, in the absence of specific inhibitors of PKCδ activity, a direct functional relevance for PKCδ in human neutrophils has not been established2 and genetic manipulation of human neutrophils is essentially impossible due to the very short life span of these cells. ...we evaluated the expression of epitopes and the adhesive and migratory properties of the patients' neutrophils (see Fig E6 in this article's Online Repository at www.jacionline.org).\n Degranulation and release of proteases Degranulation of azurophilic and specific granules from control and patients' neutrophils was measured by monitoring the cell surface upregulation of CD63 and CD66b, which are azurophilic and specific granules markers, respectively.
Systemic-onset juvenile idiopathic arthritis is an inflammatory disease of unknown cause and is not commonly associated with kidney involvement. We describe 3 patients with systemic-onset juvenile ...idiopathic arthritis with high disease activity who developed antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis 1-6 years after the onset of systemic-onset juvenile idiopathic arthritis. Renal and systemic-onset juvenile idiopathic arthritis remission occurred in one patient under anti–interleukin 1 (anti–IL-1) treatment associated with immunosuppressive drugs. The other 2 patients developed end-stage renal disease, and one of those patients died. This report suggests that the diagnosis of ANCA-associated glomerulonephritis must be considered in patients with systemic-onset juvenile idiopathic arthritis with persistently active systemic disease who present with proteinuria. Furthermore, use of an anti–IL-1 agent might be an effective therapeutic option.