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| Image created by Dr. Michael J. Miller |
HIV is one of the world’s most serious public health challenges, and molecular detection plays a significant role in early diagnosis and antiretroviral therapy for HIV patients. The current “gold standard” of HIV testing requires expensive instruments and highly-trained personnel—leaving an unmet need for a rapid, sensitive, and affordable approach for molecular detection of HIV at the point of care.
Published in the American Chemical Society’s (ACS) journal ACS Nano, a research team led by Changchun Liu in the Department of Biomedical Engineering present a low-cost, bioinspired Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-powered biosensor for point of care testing of the HIV virus using a simple personal glucose meter—similar to diabetes home testing.
“Inspired by the multicompartment structures in living cells, we propose a membrane-separated, microfluidic, CRISPR-powered cascade reaction system,” Liu says, “by combining with personal glucose biosensing technology, it is developed into a portable, disposable diagnostic platform for molecular detection of HIV virus and other pathogens.”
Dr. David Banach in the Division of Infectious Diseases in the School of Medicine, Lori Avery in the Department of Pathology of Laboratory Medicine, and Ziyue Li, Naoki Uno, and Xiong Ding in the Department of Biomedical Engineering also contributed to this study.
CRISPR technology is on the cutting edge for highly sensitive and specific nucleic acid-based molecular detection of different pathogens. When used alongside simple isothermal amplification technologies, it becomes a powerful diagnostic tool. However, the combination of isothermal amplification reaction and CRISPR detection systems have limited capabilities, requiring separate reaction tubes and multiple manual operations which increases the risk of contamination and is not ideal for simple and effective point of care applications.
To improve compatibility, the researchers presented a nanoporous membrane-separated cascade reaction system and integrated it into a simple, portable CRISPR-mediated cascade reaction (MCR) biosensor for HIV nucleic acid testing using a low-cost glucose meter to eliminate the need for complex instruments and well-trained personnel.
The researchers were able to detect sensitivities of 43 copies of HIV DNA and 200 copies of HIV RNA per test—exhibiting great potential for rapid detection of HIV virus and other infectious diseases at the point of care.
“Globally, HIV infection has a disproportionate impact on underserved populations with limited access to laboratory testing,” says Banach. “This technology has the potential to bring point of care HIV testing to settings where early diagnosis and monitoring during treatment are critical.”
In September 2020, Liu was awarded a $1.4 million grant from the National Institutes of Health to develop this simple, rapid, affordable HIV testing device.
Reference
Bioinspired CRISPR-Mediated Cascade Reaction Biosensor for Molecular Detection of HIV Using a Glucose Meter. Ziyue Li, Naoki Uno, Xiong Ding, Lori Avery, David Banach, and Changchun Liu. ACS Nano 2023, 17, 4, 3966–3975. https://doi.org/10.1021/acsnano.2c12754
Abstract
HIV molecular detection plays a significant role in early diagnosis and antiretroviral therapy for HIV patients. CRISPR technology has recently emerged as a powerful tool for highly sensitive and specific nucleic acid based molecular detection when used in combination with isothermal amplification. However, it remains a challenge to improve the compatibility of such a multienzyme reaction system for simple and sensitive molecular detection. Inspired by the multicompartment structures in a living cell, we present a nanoporous membrane-separated (compartmentalized), artificial, cascade reaction system to improve the compatibility of a CRISPR-mediated multienzyme reaction. We further integrated the multienzyme cascade reaction system with a microfluidic platform and glucose biosensing technology to develop a bioinspired, CRISPR-mediated cascade reaction (CRISPR-MCR) biosensor, enabling HIV molecular detection by a simple glucose meter, analogous to diabetes home testing. We applied the bioinspired CRISPR-MCR biosensor to detect HIV DNA and HIV RNA, achieving a detection sensitivity of 43 copies and 200 copies per test, respectively. Further, we successfully validated the bioinspired biosensor by testing clinical plasma samples of HIV, demonstrating its great application potential for point-of-care testing of HIV virus and other pathogens at home or in resource-limited settings.