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.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
7R01EB012946-02
Application #
8308073
Study Section
Instrumentation and Systems Development Study Section (ISD)
Program Officer
Korte, Brenda
Project Start
2011-03-01
Project End
2015-01-31
Budget Start
2011-09-01
Budget End
2012-01-31
Support Year
2
Fiscal Year
2011
Total Cost
$164,781
Indirect Cost
Name
California Institute of Technology
Department
Engineering (All Types)
Type
Schools of Engineering
DUNS #
009584210
City
Pasadena
State
CA
Country
United States
Zip Code
91125
Selck, David A; Ismagilov, Rustem F (2016) Instrument for Real-Time Digital Nucleic Acid Amplification on Custom Microfluidic Devices. PLoS One 11:e0163060
Schoepp, Nathan G; Khorosheva, Eugenia M; Schlappi, Travis S et al. (2016) Digital Quantification of DNA Replication and Chromosome Segregation Enables Determination of Antimicrobial Susceptibility after only 15?Minutes of Antibiotic Exposure. Angew Chem Int Ed Engl 55:9557-61
Khorosheva, Eugenia M; Karymov, Mikhail A; Selck, David A et al. (2016) Lack of correlation between reaction speed and analytical sensitivity in isothermal amplification reveals the value of digital methods for optimization: validation using digital real-time RT-LAMP. Nucleic Acids Res 44:e10
Rodriguez-Manzano, Jesus; Karymov, Mikhail A; Begolo, Stefano et al. (2016) Reading Out Single-Molecule Digital RNA and DNA Isothermal Amplification in Nanoliter Volumes with Unmodified Camera Phones. ACS Nano 10:3102-13
Sun, Bing; Rodriguez-Manzano, Jesus; Selck, David A et al. (2014) Measuring fate and rate of single-molecule competition of amplification and restriction digestion, and its use for rapid genotyping tested with hepatitis C viral RNA. Angew Chem Int Ed Engl 53:8088-8092
Kelley, Shana O; Mirkin, Chad A; Walt, David R et al. (2014) Advancing the speed, sensitivity and accuracy of biomolecular detection using multi-length-scale engineering. Nat Nanotechnol 9:969-80
Sun, Bing; Shen, Feng; McCalla, Stephanie E et al. (2013) Mechanistic evaluation of the pros and cons of digital RT-LAMP for HIV-1 viral load quantification on a microfluidic device and improved efficiency via a two-step digital protocol. Anal Chem 85:1540-6
Begolo, Stefano; Shen, Feng; Ismagilov, Rustem F (2013) A microfluidic device for dry sample preservation in remote settings. Lab Chip 13:4331-42
Selck, David A; Karymov, Mikhail A; Sun, Bing et al. (2013) Increased robustness of single-molecule counting with microfluidics, digital isothermal amplification, and a mobile phone versus real-time kinetic measurements. Anal Chem 85:11129-36
Pompano, Rebecca R; Platt, Carol E; Karymov, Mikhail A et al. (2012) Control of initiation, rate, and routing of spontaneous capillary-driven flow of liquid droplets through microfluidic channels on SlipChip. Langmuir 28:1931-41

Showing the most recent 10 out of 13 publications