Label-free HIV-1 Viral Load Measurement through a Contactless Electrode Microchip

描述：快速、廉价和早期检测传染性病毒疾病是一个迫切的未得到满足的需求，其应用范围广泛，从临床诊断、公共卫生和国土安全。在这些应用中，资源有限环境下的人类免疫缺陷病毒(HIV-1)诊断在为患者提供适当和及时的护理方面发挥着至关重要的作用。据报告，95%以上死于疟疾、获得性免疫缺陷综合征(AIDS)和结核病(TB)等传染病的病例发生在发展中国家。在3330万艾滋病毒-1感染人口中，有很大比例(67%)生活在撒哈拉以南非洲。这些统计数据清楚地突显了对快速、廉价和简单的筛查测试的迫切需求，以确定艾滋病毒/艾滋病治疗的感染者。然而，目前的艾滋病毒-1诊断方法，如侧流分析，包括试纸或酶免疫分析(ELISA)，以及OraQuick艾滋病毒检测试剂盒，即使在艾滋病毒-1病毒载量较高的情况下，也缺乏检测急性艾滋病毒-1感染的能力。检测急性HIV-1感染者至关重要，因为病毒复制和脱落发生在可检测到的HIV-1抗体出现之前的这一阶段。急性艾滋病毒-1感染者不知道自己的疾病，因此极大地助长了艾滋病毒-1的传播。在这个阶段，有最大的病毒复制和脱落(108拷贝/毫升)。因此，迫切需要一种易于使用、便携和廉价的诊断工具，用于POC的急性HIV-1检测(血清转换和无症状阶段)。在哈佛医学院的生物-声学MEMS医学实验室，Demirci博士(赞助商)的团队展示了基于无透镜和荧光成像的病毒载量计算平台的原型。在这里，我将运用我以前在微流控细胞电操作方面的专业知识，以及我目前在使用微/纳米技术捕获基于抗体的HIV-1病毒方面的专业知识，创建一个用于治疗启动和监测的POC HIV-1病毒载量测量平台。链霉亲和素包被的纳米磁珠与gp120抗体偶联，将用于从全血样本中选择性捕获和分离HIV-1病毒。然后将纳米Beadad-HIV病毒复合体引入微流控设备，优化的非接触式微电极与gp120抗体功能化，以捕获纳米Beadad-HIV复合体。捕获的病毒将通过引入裂解洗涤剂进行裂解，阻抗变化将与样本的病毒载量相关。这项提议将为POC的HIV-1病毒载量测量提供一种廉价的方法，该方法与大规模制造技术兼容，具有很大的商业化前景。

DESCRIPTION: Rapid, inexpensive, and early detection of infectious viral diseases is an urgent unmet need with diverse applications ranging from clinical diagnosis, public health, and homeland security. Among these applications, Human Immunodeficiency Virus (HIV-1) diagnostics in resource-limited settings plays a critical role to provide appropriate and timely care to patients. More than 95% of deaths due to infectious diseases such as malaria, Acquired Immune Deficiency Syndrome (AIDS), and tuberculosis (TB) have been reported to occur in developing countries. A significant ratio (67%) of the 33.3 million HIV-1 infected population live in Sub-Saharan Africa. These statistics clearly highlight the urgent demand for rapid, inexpensive, and simple screening tests to identify infected individuals for HIV/AIDS treatment. However, current HIV-1 diagnostics such as lateral flow assays, including dipsticks or enzyme immunoassays (ELISA), and OraQuick HIV test kit lack the capability to detect acute HIV-1 infection even at high HIV-1 viral load. Detecting persons with acute HIV-1 infection is crucial since viral replication and shedding occur in this stage before detectable HIV-1 antibodies appear. Persons with acute HIV-1 infection are unaware of their disease and therefore contribute substantially to HIV-1 transmission. At this stage, there is maximum viral replication and shedding (108 copies/mL). Thus, there is an immediate need for easy to use, portable, and inexpensive diagnostic tool for acute HIV-1 detection (seroconversion and asymptomatic stages) at the POC. At the Bio-Acoustic MEMS in Medicine laboratory at Harvard Medical School, Dr. Demirci's (Sponsor) team has presented prototype viral load counting platforms based on lensless and fluorescence imaging. Here, I will employ my previous expertise in microfluidic cell electro-manipulation and my current expertise in antibody based HIV-1 virus capturing using micro/nano technologies to create a POC HIV-1 viral load measurement platform for treatment initiation and monitoring. Streptavidin-coated nano-magnetic beads conjugated with gp120 antibody will be used to selectively capture and isolate HIV-1 viruses from whole blood samples. The nanobead-HIV virus complexes will be then introduced into the microfluidic device with the optimized contactless microelectrodes functionalized with gp120 antibody to capture the nanobead-HIV complex. The captured viruses will be lysed through introducing a lysis detergent and the impedance change will be correlated to the viral load of the sample. This proposal will provide an inexpensive method for HIV-1 viral load measurements at POC that is compatible with mass fabrication technologies with a great promise to be commercialized.