Multiplexed Antigen-Specific Antibody Fc Profiling on a Chip for Point-of-Care Diagnosis of TB in HIV-infected Children

摘要： 结核病是导致儿童死亡的主要原因，估计有100万儿童。 每年有200,000多名儿童死于结核病。艾滋病毒混合感染一直是 据估计，在非洲儿童与结核病有关的死亡中，超过35%是由结核病造成的，这使得 艾滋病毒和结核病疫情的碰撞是迄今为止最致命的疫情之一。艾滋病毒感染以及 在感染艾滋病毒但未感染(HEU)的儿童中，在宫内接触艾滋病毒与 幼儿罹患结核病的风险更高。未能预防结核病和 造成破坏的原因是缺乏有效的疫苗，以及我们无法 诊断5岁以下儿童因取痰困难和 少年儿童的少菌性疾病。因此，一种廉价的基于生物标志物的 使用非痰样本为儿童结核病量身定做的诊断测试，可用于 在资源有限的环境中提供护理可以深刻地改善结核病的治疗和 预防儿童死亡，特别是5岁以下儿童死亡。而特定于MTB 基于抗体滴度的诊断在过去表现不佳，原因是无法 准确区分活动性结核病和潜伏性结核病感染(LTBI)，最新数据 来自我们小组的研究表明，结核分枝杆菌特异性抗体的糖基化显著地 疾病状态。此外，这种抗原特异性抗体糖基化方法可以可靠地将 不同地理位置的HIV感染状态中处于活跃和潜在疾病状态的个体 甚至可以区分最近流行地区儿童中的伤寒感染。基于 在这些观察中，一种简单的基于结合的分析被开发出来，它可以快速、灵敏地 并从小样本体积中专门检测结核分枝杆菌特异性抗体糖基化的变化 首次提供了开发抗原特异性抗体糖基化的机会 从微升样本中诊断儿童结核病。鉴于HIV+、HEU或 未接触过的儿童可能会针对不同的结核分枝杆菌抗原，在这里我们聚集了一个多学科的 团队和项目名为FASTER-Kids(儿童结核病FC抗体签名) 这将：1)定义结核分枝杆菌特异性抗体糖基化反应的图景，区分 患有结核病的儿童，2)开发了一种护理点测试，可以迅速捕获这些特定的抗体 微升血液的反应和糖基化变化。最终，这一协作 结构将使这种简单、快速、廉价的迭代改进和开发成为可能 诊断以管理幼儿中的结核病感染。

Abstract: Tuberculosis (TB) is a leading cause of death in children, with an estimated 1 million children affected, and more than 200,000 deaths in children yearly due to TB. HIV coinfection has been estimated to contribute to more than 35% of TB-related deaths in children in Africa, making the collision of the HIV and TB epidemics one of the most lethal to date. Both HIV infection as well as HIV-exposure in utero, among HIV-exposed but uninfected (HEU) children, have been linked to higher risks for the development of TB among young children. Failures to prevent TB disease and devastation has been attributed to the lack of an effective vaccine as well as our inability to diagnose children under the age of 5 due to the difficulty in obtaining sputum and the paucibacillary nature of the disease in young children. Thus, an inexpensive biomarker-based diagnostic test tailored for pediatric TB using non-sputum samples that could be used at the point of care in resource-limited settings could profoundly improve TB treatment and prevent deaths in children, especially in those under 5 years of age. While Mtb-specific antibody titer-based diagnostics have performed poorly in the past, due to the inability of accurately distinguishing between active TB disease from latent TB infection (LTBI), recent data from our group has shown that Mtb-specific antibody glycosylation shifts significantly across disease states. Moreover, this antigen-specific antibody glycosylation approach reliably classifies individuals into active and latent disease states across HIV infection status, across geographies and can even distinguish recent Typhoid infection among children in endemic areas. Based on these observations, a simple binding-based assay was developed that can rapidly, sensitively, and specifically detect changes in Mtb-specific antibody glycosylation from a small sample volume offering an opportunity for the first time to develop an antigen-specific antibody glycosylation diagnostic for pediatric TB from a microliter-scale sample. Given that HIV+, HEU, or unexposed children may target distinct Mtb antigens, here we have assembled a multi-disciplinary team and program termed FASTER-Kids (Fc Antibody Signatures for TubERculosis in children) that will: 1) Define the landscape of Mtb-specific antibody glycosylation responses that distinguish children with TB, 2) Develop a point-of-care test that will rapidly capture these specific antibody responses and glycosylation changes from microliters of blood. Ultimately, this collaborative structure will enable the iterative improvement and development of this simple, rapid, inexpensive diagnostic to manage TB infection in young children.