According to a 2006 Centers for Disease Control report on HIV prevalence, more than a million people live with HIV in the United States. One in every five Americans with HIV is unaware of having the infection.
A group of UC researchers has developed a new HIV blood test that requires less blood, less time and less expensive equipment.
UC Davis biomedical engineer professor Alexander Revzin and his Davis team recently collaborated with UCLA professor Aydogan Ozcan to develop the new “lab on a chip” device.
Currently, an accurate diagnosis of HIV requires measuring the presence of inflammatory proteins – called cytokines – and two types of white blood cells – called T-cells. Scientists then monitor the ratio between the two different T-cells. Revzin’s new device detects these levels in seconds using antibodies specific to the T-cells affected by the HIV virus and the three types of cytokines they release.
The old method requires expensive, heavy machines and many highly trained specialists. The new “lab on a chip” device returns results six to 12 time faster and tests six parameters simultaneously. The newly developed microfluidic test could make HIV testing more affordable and accessible in areas where HIV is most prevalent.
Judy Van de Water, a researcher at the UC Davis M.I.N.D. Institute, worked alongside Revzin on this project. Van de Water identified the test’s need for only a finger-prick versus a vial of blood as a major benefit.
“You now have this whole platform you can use to tailor to whatever you want to study, and you can use a very small amount of blood to do so.”
Researchers hope that the new technology can help in parts of the world that don’t have easy access to traditional HIV testing methods.
“Point-of-care HIV testing is more beneficial to sub-Saharan Africa than it is to Davis. However, the concept of testing multiple [diseases] from blood using an inexpensive technology is important for non-AIDS applications relevant in the U.S.,” Revzin said.
The team uses a special imaging technique that eliminates the need for lenses and mechanical scanning in HIV testing, allowing scientists to rapidly image and count the T-cell numbers.
“Instead of detecting the image of the cell, you essentially detect their shadows – light waves can penetrate through the cells and create structured shadows that have texture to them,” Ozcan said.
“You can treat the shadow of the cells as the fingerprint and can construct the image of the cell as if you were looking through a microscope.”
Without the need for lenses, the method is not just potentially 12 times faster, but also eliminates the cost of instruments like microscopes.
“By replacing the conventional microscope with lens-free imaging, we get rid of those lenses and replace them with computer codes which can process that image,” Ozcan said. “It’s a way to cut down on the cost and size and put together a platform that would normally replace a bulky instrument.”
In addition to cost, size and time, Revzin believes this test is more thorough in its analysis compared to other HIV testing.
“What sets our technology apart is that we aim to query multiple blood-based markers at the point of care. Our device would be more informative in terms of a patient’s condition compared to what other researchers are developing,” Revzin said.
Revzin hopes future tests using this technology could help detect diseases like autism and cancer.
“The Davis community may not benefit directly from inexpensive HIV testing, however, the same principle or device can be applied for other diseases requiring immune analysis,” he said.
CAMMIE ROLLE can be reached at science@theaggie.org.
