Genetics, Pathophysiology, and Treatment of Dominant Autoinflammatory Diseases

在本报告所述期间，我们重点调查了三个领域： 第一章 化脓性关节炎、坏疽性脓疡和痤疮（PAPA）综合征的研究 在过去的二十年里，我们在我们的诊所跟踪了一组患有化脓性关节炎、坏疽性化脓性坏疽和痤疮的患者。这些患者中的大多数都有PSTPIP 1基因突变，该基因编码一种已知与pyrin结合的蛋白质，该蛋白质在家族性地中海热（FMF）中突变。然而，这些患者中约有三分之一没有可证实的PSTPIP 1突变。PSTPIP 1突变阳性患者的临床表现与突变阴性的PAPA样患者重叠，但突变阳性患者发病较早，关节炎较多。与费城儿童医院的Scott Canna合作，我们发现治疗的PAPA患者血清总IL-18水平均匀升高，几乎与婴儿小肠结肠炎（AIFEC）患者的NLRC 4相关自身炎症一样高，远高于大多数FMF患者的水平。尽管疾病活动性波动，但PAPA患者血清中的IL-18升高持续存在。可溶性IL-18拮抗剂IL-18 BP适度升高，PAPA患者可检测到游离IL-18。PAPA综合征很少与CXCL 9升高相关，CXCL 9是干扰素-γ活性的指标，但没有PAPA患者有巨噬细胞活化综合征的病史。这些发现表明，pyrin炎性体激活，IL-18，和自身炎症之间的联系，而不易感巨噬细胞活化综合征。 这项工作正在出版的关节炎和风湿病学。 （二） 自身炎症性疾病中过敏相关特征的合作研究 博士NIAID的助理临床研究员Daniella Schwartz与我们小组合作研究了自身炎症性疾病的过敏表现。Schwartz博士通过问卷调查和图表审查研究了425名自身炎症性疾病患者。这些患者包括FMF、cryopyrin相关周期性综合征（CAPS）、TNF受体相关周期性综合征（TRAPS）、高IgD综合征（HIDS）、PAPA综合征、ADA 2缺陷（DADA 2）、A20单倍不足（HA 20）、慢性非典型嗜中性粒细胞皮肤病、脂肪营养不良和体温升高（CANDLE）以及STING相关婴儿血管病（SAVI）。刺激55例患者的外周血单核细胞，并评估CD 4细胞因子的产生。特别是，评估了2型辅助性T细胞应答，这是过敏性炎症的典型特征。 FMF和CANDLE与辅助性T细胞2型反应降低和临床过敏发生率低有关。CAPS与嗜酸性粒细胞增多、临床过敏和Th 2扩增相关。包括DADA 2在内的几种自身炎症性疾病与Th 2应答降低有关，但医生诊断的过敏症的患病率很高，这表明自身炎症可以伪装成过敏性疾病。 数据表明，医生应将2型免疫视为CAPS的一个因素，但应谨慎将其他自身炎症性疾病的过敏症状归因于2型免疫激活，因为这些特征可能是由于未经治疗的自身炎症。了解先天免疫基因如何调节过敏表型将为先天免疫在过敏相关疾病中的作用提供新的见解，并可能在2型免疫调节剂治疗难治性患者中确定新的靶点。 这项工作正在《风湿病年鉴》上出版。 第三章 一项通过突变ADGRE 2检查人肥大细胞机械活化信号传导的合作研究 在较早的报告期，我们发现了一个显性遗传p.C492Y突变的G蛋白偶联受体ADGRE 2（EMR 2）的家族性振动性荨麻疹患者。在这些患者中，皮肤摩擦通过p. C492 Y-ADGRE 2诱导肥大细胞过度脱粒，引起局部荨麻疹、潮红和低血压。ADGRE 2在中性粒细胞、单核细胞和肥大细胞中表达。在这项合作研究中，Andrea Naranjo、Dean Metcalfe和安娜奥利维拉博士检查了表达p. C492 Y-ADGRE 2并附着于ADGRE 2配体硫酸皮肤素的人肥大细胞中机械活化引起的细胞内信号。他们发现，突变ADGRE 2的存在降低了激活阈值，并增加了脱粒的程度沿着肥大细胞应答的百分比。振动引起磷脂酶C激活，胞质钙离子瞬时增加，磷酸肌醇3激酶和细胞外信号调节激酶1和2的下游激活。振动诱导的脱粒依赖于磷脂酶C途径，包括钙、蛋白激酶C和磷酸肌醇3-激酶，但不依赖于细胞外信号相关激酶1/2途径，沿着百日咳毒素敏感信号。此外，肥大细胞的机械活化刺激前列腺素D2的合成和释放，前列腺素D2是振动性荨麻疹中以前未报道的介质，这种反应需要细胞外信号相关激酶1/2激活以及钙、蛋白激酶C和在一定程度上磷酸肌醇3-激酶。因此，这些研究确定了振动性荨麻疹患者由机械力引发的关键分子事件和潜在的治疗靶点。 这项研究发表在11月的《皮肤病学研究杂志》上。

During the current reporting period we focused on three areas of investigation: 1) Studies of pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome For the last two decades, we have followed a cohort of patients with pyogenic arthritis, pyoderma gangrenosum, and acne in our clinic. Most of these patients have mutations in the PSTPIP1 gene, which encodes a protein known to bind to pyrin, the protein mutated in familial Mediterranean fever (FMF). However, about one third of these patients have no demonstrable PSTPIP1 mutations. PSTPIP1 mutation-positive patients' clinical findings overlapped with mutation-negative PAPA-like patients, but mutation-positive patients had earlier onset and more arthritis. In collaboration with Scott Canna at the Childrens Hospital of Philadelphia, we found uniform elevation of total serum IL-18 in treated PAPA patients at levels nearly as high as NLRC4-associated autoinflammation with infantile enterocolitis (AIFEC) patients and well above levels in most FMF patients. IL-18 elevation in PAPA patients' serum persisted despite fluctuations in disease activity. The soluble IL-18 antagonist IL-18BP was modestly elevated, and PAPA patients had detectable free IL-18. PAPA syndrome was rarely associated with elevation of CXCL9, an indicator of interferon-gamma activity, but no PAPA patients had histories of macrophage activation syndrome. These findings suggest a link between pyrin inflammasome activation, IL-18, and autoinflammation without susceptibility to macrophage activation syndrome. This work is in press in Arthritis and Rheumatology. 2) A collaborative study of allergy-associated features in autoinflammatory disease Dr. Daniella Schwartz, an Assistant Clinical Investigator in the NIAID, collaborated with our group to study allergic manifestations in autoinflammatory disease. Dr. Schwartz studied 425 patients with autoinflammatory disease with questionnaires and chart reviews. These included patients with FMF, cryopyrin-associated periodic syndrome (CAPS), TNF receptor-associated periodic syndrome (TRAPS), hyper-IgD syndrome (HIDS), PAPA syndrome, deficiency of ADA2 (DADA2), haploinsufficiency of A20 (HA20), chronic atypical neutrophilic dermatosis, lipodystrophy, and elevated temperature (CANDLE), and STING-associated vasculopathy of infancy (SAVI). Peripheral blood mononuclear cells from 55 patients were stimulated and CD4 cytokine production assessed. In particular, T helper type 2 responses, which are typical of allergic inflammation, were assessed. FMF and CANDLE were associated with reduced T helper Type 2 responses and a low prevalence of clinical allergy. CAPS is associated with eosinophilia, clinical allergy, and Th2 expansion. Several autoinflammatory diseases, including DADA2, are associated with reduced Th2 responses but a high prevalence of physician-diagnosed allergy, suggesting that autoinflammation can masquerade as allergic disease. The data indicate that physicians should consider Type 2 immunity as a factor in CAPS but should be cautious in attributing allergic symptoms in other autoinflammatory diseases to type 2 immune activation, as these features could be due to untreated autoinflammation. Understanding how innate immune genes modulate allergic phenotypes will provide new insights into the role of innate immunity in allergy-associated diseases and may identify novel targets in patients refractory to treatments targeting type 2 immunomodulators. This work is in press in the Annals of the Rheumatic Diseases. 3) A collaborative study examining signaling in the mechanoactivation of human mast cells through mutant ADGRE2 In an earlier reporting period, we discovered a dominantly inherited p.C492Y mutation in the G-protein coupled receptor ADGRE2 (EMR2) in patients with familial vibratory urticaria. In these patients, friction of the skin induces mast cell hyper-degranulation through p.C492Y-ADGRE2, causing localized hives, flushing, and hypotension. ADGRE2 is expressed in neutrophils, monocytes, and mast cells. In this collaborative study, Drs. Andrea Naranjo, Dean Metcalfe, and Anna Olivera examined the intracellular signals elicited by mechanical activation in human mast cells expressing p.C492Y-ADGRE2 and attached to dermatan sulfate, a ligand for ADGRE2. They found that the presence of mutant ADGRE2 reduced the threshold to activation and increased the extent of degranulation along with the percentage of mast cells responding. Vibration caused phospholipase C activation, transient increases in cytosolic calcium, and downstream activation of phosphoinositide 3-kinase and extracellular signal-regulated kinases 1 and 2. Degranulation induced by vibration was dependent on phospholipase C pathways, including calcium, protein kinase C, and phosphoinositide 3-kinase but not extracellular signal-related kinases 1/2 pathways, along with pertussis toxin-sensitive signals. In addition, mechanoactivation of mast cells stimulated the synthesis and release of prostaglandin D2, a previously unreported mediator in vibratory urticaria, and extracellular signal-related kinases 1/2 activation was required for this response together with calcium, protein kinase C, and to some extent phosphoinositide 3-kinase. These studies thus identified critical molecular events initiated by mechanical forces and potential therapeutic targets for patients with vibratory urticaria. This work was published in November in the Journal of Investigative Dermatology.