Digital SlipChip Technology for POC and Resource-Limited Viral Load Measurements

点击翻译按钮获取中文摘要

DESCRIPTION (provided by applicant): HIV is a significant global health problem- recent estimates suggest ~33 million people living with HIV, with 96% residing in the developing world. While HIV antiretroviral therapy is effective and increasingly available, quantitative monitoring of treatment is necessary to provide proper care to patients, and to control the emergence and spread of drug-resistant strains of HIV worldwide. Such tests are urgently needed for resource-limited settings to avoid staggering increases in health care costs associated with drug resistance and switching to second- and third-line therapies. However, current inexpensive, qualitative, yes/no diagnostic tools cannot guide treatment or monitor drug resistance, and current quantitative PCR-based assays require expensive equipment and complex environments unsuitable for point-of-care (POC) in resource-limited settings. Additionally, isolating and concentrating viral RNA is challenging for most POC approaches. The SlipChip is a highly innovative technology from the PI's laboratory that uniquely combines a high level of performance with simplicity of fabrication and operation. The chip consists of two plates that move- or "slip"- relative to one another, lubricated by a fluid that is immiscible with the sample fluid and also provides control of surface chemistry and prevents cross-contamination. Slipping brings wells in the two plates in and out of contact to execute a diagnostic assay, and manipulations of volume ranging over 7 orders of magnitude (e.g. from 100 pL to 1 mL) can be performed on the same chip. The SlipChip will facilitate integration of i) upstream sample preparation to isolate and concentrate viral RNA with ii) quantification of viral particles via nucleic acid amplification using "digital" (single molecule) detection using isothermal amplification chemistries, with iii) downstream signal amplification to enable simple readout. The team that includes PI, co-PIs and a diverse set of industrial and global health collaborators has expertise spanning development of innovative micro-technologies, to molecular biology of RNA and isothermal nucleic acid amplification, to clinical use of diagnostic assays, to development and dissemination of FDA- approved diagnostics tests, to manufacturing, filling and packaging of plastic disposables, to manufacturing of diagnostic equipment, to working with AIDS patients both in the US and in India and Nigeria. This team would ensure that all research is done in the correct context of global health and in the context of chemistries, disposables, and equipment that can be manufactured inexpensively and used in resource-limited settings. The development of a POC device to monitor HIV viral loading fits within two of the five priorities of the NIH as articulated by Director Francis Collins: it will have a large impact on global health, and it has the potential to ultimately reduce healthcare costs in the US. Long term, this work would lead to SlipChip platform as a "disruptive innovation" to improve healthcare by reducing costs, and simplifying and increasing availability and applicability of nucleic acid-based molecular diagnostics. PUBLIC HEALTH RELEVANCE: Over 33 million people worldwide are living with HIV, the majority of them in resource-limited settings, with anti- retroviral drugs becoming more and more widely available; however, without technologies for monitoring viral load in patients on anti-retroviral drugs, drug resistant strains of HIV will emerge and spread. This work will develop a SlipChip-based platform to measure the HIV viral load at the point of care inexpensively and simply to prevent a global health care catastrophe caused by emergence and spread of drug-resistant HIV. This work is also likely to act in the US as a "disruptive technology" to improve healthcare and reduce costs.