Eosinophils and Eosinophil Activation in the Pathogenesis of Human Disease

人类疾病发病机制中的嗜酸性粒细胞和嗜酸性粒细胞激活

• 批准号: 9161679
• 负责人: Amy Klion
• 金额: $ 125.83万
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9161679
• 关键词: Adrenal gland hypofunction; Adverse effects; Aftercare; Amyotrophic Lateral Sclerosis; Angioneurotic Edema; Antibodies; Apoptosis; Asthma; Benign; Biological; Biological Markers; Blood; Bone Marrow; Bone Tissue; Cells; Cessation of life; Clinical Trials; Clinical Trials Design; Collaborations; Data; Data Analyses; Dermatitis; Development; Diethylcarbamazine; Disease; Disease remission; Disseminated eosinophilic collagen disease; Double-Blind Method; Drug Hypersensitivity; Engineering; Enrollment; Eosinophil Granule Proteins; Eosinophilia; Eosinophilic leukemia; Etiology; Experimental Autoimmune Encephalomyelitis; Extrinsic asthma; Family; Feces; Flow Cytometry; Genetic study; Glucocorticoids; Goals; Helminths; Homeostasis; Hypersensitivity; IgG1; IgG4; Imatinib; In complete remission; Infection; Interleukin-2; Interleukin-5; International; Ligands; Liquid substance; Loa loa; Loiasis; Lymphocyte; Manuscripts; Measures; Methods; Microfilaria; Monitor; Mus; Myeloproliferative disease; Outcome Measure; PDGFRA gene; Paper; Parasitic infection; Pathogenesis; Patient Outcomes Assessments; Patients; Pharmaceutical Preparations; Phase; Phase II Clinical Trials; Phase III Clinical Trials; Placebo Control; Plasma; Rare Diseases; Reaction; Refractory; Role; Severe Adverse Event; Societies; Sputum; Steroid Resistance; Subgroup; Suspension substance; Suspensions; Symptoms; Syndrome; System; Therapeutic; Tissues; Transgenic Organisms; Urine; Whole Blood; Work; clinical efficacy; cohort; contrast enhanced; cytokine; effective therapy; eosinophil; gastrointestinal; human SIGLEC8 protein; human disease; in vitro Assay; inhibitory surface receptor; mast cell; mastocytosis; meetings; mepolizumab; mouse model; neoplastic; neutrophil; novel; novel diagnostics; open label; pediatric patients; peripheral blood; placebo controlled study; pre-clinical; prevent; receptor; response; stem; targeted treatment; tool

Using a cohort of more than 400 subjects with a wide variety of eosinophilic disorders, ranging from benign eosinophilia to eosinophilic leukemia, we have continued to identify and characterize novel subgroups of patients with eosinophilia. Episodic Angioedema with Eosinophilia (EAE; Gleichs Syndrome) is a rare disorder characterized by episodes of angioedema and eosinophilia that occur at monthly intervals and resolve spontaneously without therapy. Although the etiology of EAE is not yet known, we have demonstrated that multiple lineages, including lymphocytes, neutrophils and mast cells, are involved and may be related to disease pathogenesis (Khoury et al. Haematologica 2015). Whether these cells act directly or promote eosinophilia and eosinophil activation remains to be elucidated. Genetic studies are currently underway. Other subgroups of eosinophilic subjects currently under study include families with autosomal dominant eosinophilia, pediatric patients (Williams et al. J Allergy Clin Immunol 2014:133:AB149, paper submitted), and a cohort of subjects with eosinophilic dermatitis (Khoury et al. J Allergy Clin Immunol 2015:135:AB266). Therapy for eosinophilic disorders remains a primary focus of our group. In the past year, we have reached 50% enrollment in two clinical trials of targeted therapy for the treatment of HES. The first of these is a placebo-controlled, double-blind phase 2 trial of benralizumab (MedImmune/Astra Zeneca), an afucosylated antibody to IL-5 receptor alpha that has shown clinical efficacy in patients with eosinophilic asthma. The current trial stems, in part, from our prior pre-clinical work examining IL-5 receptor levels in patients with eosinophilia and/or mastocytosis (Wilson et al. J Allergy Clin Immunol 2011). To date, 10 of 20 planned subjects have been enrolled, of which 8 have entered the open-label phase of the study. The drug has been well-tolerated and early efficacy results are promising. The second trial is an open-label trial of dexpramipexole (Knopp Biosciences) in patients with steroid-resistant HES. Dexpramipexole was developed for the treatment of amyotrophic lateral sclerosis (ALS). Although it was well tolerated, dexpramipexole failed to show efficacy in a large phase 3 trial for this disease. It did, however, appear to selectively lower blood eosinophils, which prompted the current proof-of-concept open-label phase 2 trial in HES. To date, 5 of the 10 planned subjects have been enrolled. The drug has been well-tolerated and early efficacy results are encouraging. We have also completed enrollment in a new multicenter placebo-controlled, double-blind phase 3 clinical trial of mepolizumab (anti-IL-5 antibody) for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA). In addition to the clinical trials described above, we continue to explore standard therapies for HES. We have analyzed data from an ongoing clinical trial of imatinib in subjects with FIP1L1/PDGFRA-positive myeloproliferative neoplasm (FP), PDGFRA-negative HES with myeloproliferative features (MP) and steroid-resistant without myeloproliferative features (SR) (Khoury et al. presented at the annual meeting of the International Eosinophil Society; manuscript submitted). Overall, imatinib response rates were 100% in the FP group (n= 16), 50% in the MP group (n=13) and 0% in the SR group (n=16). The presence of ≥ 4 myeloproliferative features was the sole predictor of response. After ≥ 18 months in complete remission, imatinib was tapered and discontinued in 8 FP and 1 MP subjects. Seven subjects (6 FP, 1 MP) remain in remission off therapy for a median of 29 months (range 14-36). We have also continued to enroll subjects in a double-blind clinical trial designed to assess the utility of a glucocorticoid challenge in determination of glucocorticoid responsiveness in HES and in a clinical trial of mepolizumab (humanized anti-IL-5 antibody) for treatment-refractory HES. Finally, in collaboration with GlaxoSmithKline and ICON, we have begun to collect data for development of a PRO (patient-reported outcome measure) for use in clinical trials in HES. We continue to explore the therapeutic potential of novel antibodies with the potential to target eosinophils, including two antibodies to the inhibitory surface receptors, siglec-8. Siglec-8 is an inhibitory receptor highly expressed on mature eosinophils in blood, bone marrow and tissue. Engagement of the receptor by its ligand or anti-Siglec 8 antibody induces eosinophil apoptosis in the presence of IL-5. Siglec-8 expression was quantified by flow cytometry using whole blood from 38 normal donors (ND) and 58 subjects with HES and was found to be high on eosinophils from normal and HES subjects, irrespective of HES subtype or therapy. Two humanized anti-Siglec-8 antibodies are currently in pre-clinical development, an IgG4 antibody and an IgG1 antibody that has been engineered to cause enhanced ADCC. We have demonstrated that both IgG1 and IgG4 anti-siglec 8 antibodies induce eosinophil apoptosis with similar efficiency in an in vitro assay using whole blood from normal and eosinophilic subjects in the presence of IL-5. In contrast, enhanced ADCC is observed only with the IgG1 antibody and may be limited in patients with very high eosinophil counts and a low NK:EO ratio (Legrand et al. J Allergy Clin Immunol 2015;135:AB221). Murine studies with the two antibodies are currently underway using a humanized IL-2 transgenic NOG mouse model. Helminth infections can be associated with dramatic eosinophilia and complications that are indistinguishable from HES. This is particularly true in loiasis where symptoms are associated with increased eosinophil granule protein levels (indicative of eosinophil activation and degranulation) as well as elevated levels of eosinophil-associated cytokines (Herrick et al. Clin Inf Dis 2015;60:55-63). In some infections, eosinophilia and eosinophil-related symptoms can be exacerbated by effective treatment. For example, treatment of the filarial infection loiasis with diethylcarbamazine (DEC) can be associated with severe adverse events, including death, that are accompanied by a dramatic rise in eosinophilia and are positively correlated with the number of circulating microfilariae in the blood. In the past year, we have enrolled the final subject in a double-blind, placebo-controlled study of the anti-IL-5 antibody, reslizumab, to prevent post-treatment side effects of DEC in patients with Loa loa infection. Finally, in the past year, we have continued to look for biomarkers of eosinophilic disease activity for use in monitoring responses to therapy and helping to dissect out the mechanisms of eosinophil pathogenesis. To this end, we have continued to explore the utility of our multiplex suspension array system developed to simultaneously measure the concentrations of 4 eosinophil granule proteins in serum and plasma (MBP, ECP, EDN and EPO) (Makiya et al. J Immunol Methods 2014) in biological fluids including stool, sputum and urine. Data to date suggest that increased levels of eosinophil granule proteins in stool may be a useful marker of gastrointestinal eosinophilia (Makiya et al. presented at the annual meeting of the International Eosinophil Society 2015) .

通过使用 400 多名患有各种嗜酸性粒细胞疾病（从良性嗜酸性粒细胞增多症到嗜酸性粒细胞白血病）的受试者队列，我们​​继续识别和表征新的嗜酸性粒细胞增多症患者亚组。 发作性血管性水肿伴嗜酸性粒细胞增多（EAE；格莱克斯综合征）是一种罕见的疾病，其特征是每月发生一次血管性水肿和嗜酸性粒细胞增多，无需治疗即可自行消退。 尽管 EAE 的病因尚不清楚，但我们已经证明，包括淋巴细胞、中性粒细胞和肥大细胞在内的多种谱系都参与其中，并可能与疾病发病机制有关 (Khoury et al. Haematologica 2015)。这些细胞是否直接起作用或促进嗜酸性粒细胞增多和嗜酸性粒细胞活化仍有待阐明。遗传学研究目前正在进行中。目前正在研究的嗜酸性粒细胞受试者的其他亚组包括患有常染色体显性嗜酸性粒细胞增多症的家族、儿科患者（Williams 等人，J Allergy Clin Immunol 2014：133：AB149，提交的论文）和一组患有嗜酸性皮炎的受试者（Khoury 等人，J）过敏临床免疫学 2015：135：AB266）。 嗜酸性粒细胞疾病的治疗仍然是我们小组的主要关注点。去年，我们两项针对 HES 的靶向治疗临床试验的入组率达到了 50%。第一项是 Benralizumab（MedImmune/Astra Zeneca）的安慰剂对照、双盲 2 期试验，这是一种针对 IL-5 受体 α 的无岩藻糖基化抗体，已在嗜酸性粒细胞性哮喘患者中显示出临床疗效。 目前的试验部分源于我们之前检查嗜酸性粒细胞增多症和/或肥大细胞增多症患者的 IL-5 受体水平的临床前工作（Wilson 等人，J Allergy Clin Immunol 2011）。 迄今为止，20名计划受试者中的10名已入组，其中8名已进入研究的开放标签阶段。 该药物耐受性良好，早期疗效结果令人鼓舞。第二项试验是右旋普拉克索（Knopp Biosciences）在类固醇耐药性 HES 患者中进行的开放标签试验。右旋普拉克索被开发用于治疗肌萎缩侧索硬化症（ALS）。尽管右旋普拉克索具有良好的耐受性，但在针对该疾病的大型 3 期试验中未能显示出疗效。 然而，它似乎确实可以选择性地降低血液嗜酸性粒细胞，这促使目前在 HES 中进行概念验证开放标签 2 期试验。迄今为止，计划的 10 名受试者中已有 5 名已入组。该药物耐受性良好，早期疗效结果令人鼓舞。我们还完成了一项新的多中心安慰剂对照、双盲 3 期美泊利单抗（抗 IL-5 抗体）临床试验的入组，该试验用于治疗嗜酸性肉芽肿性多血管炎 (EGPA)。 除了上述临床试验外，我们还在继续探索 HES 的标准疗法。我们分析了一项正在进行的伊马替尼临床试验的数据，该试验的受试者为 FIP1L1/PDGFRA 阳性骨髓增殖性肿瘤 (FP)、PDGFRA 阴性 HES 伴骨髓增殖性肿瘤 (MP) 和类固醇耐药但无骨髓增殖性肿瘤 (SR)（Khoury 等，2017）。在国际嗜酸性粒细胞学会年会上发表；已提交手稿）。 总体而言，伊马替尼缓解率在 FP 组 (n=16) 中为 100%，在 MP 组 (n=13) 中为 50%，在 SR 组 (n=16) 中为 0%。 ≥ 4 个骨髓增殖特征的存在是缓解的唯一预测因素。 完全缓解 ≥ 18 个月后，8 名 FP 和 1 名 MP 受试者逐渐减量并停用伊马替尼。 7 名受试者（6 名 FP，1 名 MP）在治疗后仍处于缓解状态，中位时间为 29 个月（范围 14-36）。我们还继续招募受试者参加一项双盲临床试验，该试验旨在评估糖皮质激素激发试验在确定 HES 中糖皮质激素反应性方面的效用，以及美泊利单抗（人源化抗 IL-5 抗体）治疗难治性患者的临床试验。他。最后，我们与 GlaxoSmithKline 和 ICON 合作，开始收集数据，用于开发 PRO（患者报告的结果测量），用于 HES 的临床试验。 我们继续探索具有靶向嗜酸性粒细胞潜力的新型抗体的治疗潜力，包括两种针对抑制性表面受体的抗体 siglec-8。 Siglec-8 是一种抑制性受体，在血液、骨髓和组织中的成熟嗜酸性粒细胞上高度表达。在 IL-5 存在的情况下，受体与其配体或抗 Siglec 8 抗体的结合会诱导嗜酸性粒细胞凋亡。使用来自 38 名正常供体 (ND) 和 58 名 HES 受试者的全血，通过流式细胞术对 Siglec-8 表达进行定量，发现正常和 HES 受试者的嗜酸性粒细胞中 Siglec-8 表达较高，无论 HES 亚型或治疗如何。两种人源化抗 Siglec-8 抗体目前正处于临床前开发阶段，一种是 IgG4 抗体，另一种是 IgG1 抗体，经过改造可增强 ADCC。我们已经证明，在存在 IL-5 的情况下，使用来自正常和嗜酸性粒细胞受试者的全血进行的体外测定中，IgG1 和 IgG4 抗 siglec 8 抗体均以相似的效率诱导嗜酸性粒细胞凋亡。 相比之下，仅使用 IgG1 抗体即可观察到 ADCC 增强，并且在嗜酸性粒细胞计数非常高和 NK:EO 比率较低的患者中可能受到限制（Legrand 等人，J Allergy Clin Immunol 2015；135:AB221）。 目前正在使用人源化 IL-2 转基因 NOG 小鼠模型对这两种抗体进行小鼠研究。 蠕虫感染可能与严重的嗜酸性粒细胞增多以及与 HES 无法区分的并发症有关。 在罗阿西斯病中尤其如此，其症状与嗜酸性粒细胞颗粒蛋白水平升高（表明嗜酸性粒细胞活化和脱粒）以及嗜酸性粒细胞相关细胞因子水平升高相关（Herrick 等人 Clin Inf Dis 2015；60:55-63） 。在某些感染中，有效治疗可能会加剧嗜酸性粒细胞增多和嗜酸性粒细胞相关症状。例如，用二乙基卡马嗪 (DEC) 治疗丝虫感染罗阿病可能会导致严重的不良事件，包括死亡，同时伴随着嗜酸细胞增多的急剧增加，并且与血液中循环微丝蚴的数量呈正相关。去年，我们招募了最后一名受试者参加抗 IL-5 抗体 reslizumab 的双盲、安慰剂对照研究，以预防 Loa loa 感染患者出现 DEC 治疗后副作用。 最后，在过去的一年中，我们继续寻找嗜酸性粒细胞疾病活动的生物标志物，用于监测治疗反应并帮助剖析嗜酸性粒细胞发病机制。为此，我们继续探索我们开发的多重悬浮阵列系统的实用性，该系统可同时测量血清和血浆中 4 种嗜酸性粒细胞颗粒蛋白（MBP、ECP、EDN 和 EPO）的浓度（Makiya 等人，《免疫方法杂志》2014 ）存在于生物体液中，包括粪便、痰液和尿液。 迄今为止的数据表明，粪便中嗜酸性粒细胞颗粒蛋白水平升高可能是胃肠道嗜酸性粒细胞增多的有用标志（Makiya 等人在 2015 年国际嗜酸性粒细胞学会年会上发表）。