UCLA morphs stem cells into T-cell missiles that seek and destroy HIV

UCLA scientists have made what could be a game-changing breakthrough in the bid to defeat HIV. They engineered human blood stem cells into mature T cells that sought out and attacked the virus in tissues where it lives and grows. Importantly, mice developed to have an HIV infection closely resembling the variation in humans helped produce the finding.

The finding matters because it shows you can suppress the HIV virus in living tissues by targeting the virus with immune cells created with blood stem cells, lead researcher Scott Kitchen said in a statement. (He is from the university's David Geffen School of Medicine and the UCLA AIDS Institute.) It also offers another potential weapon that could be used to fight the virus, with researchers and drug companies generating promise with everything from vaccines to potential pharmaceutical options. And it potentially allows stem cell engineering to harness more of the body's natural defense mechanisms to beat back HIV.

But the researchers themselves caution that the process may not work the same way in humans. One warning sign: human immune cells were built back up at a lower level in the "humanized" mice used in the trials than they would be in people. This, the researchers report, left the mouse immune systems lacking complete reconstruction. A concern: HIV may mutate faster in people than in mice. In subsequent research, the team wants to address this by building T cells that target multiple parts of the HIV virus and can be tried "in more genetically matched individuals."

Kitchen and his team built on earlier research that determined such a technique was possible, but that HIV-specific T-cell receptors must be matched to a specific individual. They engineered the human blood stem cells into HIV-specific CD8 T cells--white blood cells that buttress the immune system--that seek out HIV-infested cells to destroy them. As before, testing took place in mice where the HIV infection is very similar to the human version. They found that the process helped boost the number of CD4 T cells. What's more, the engineered cells themselves migrated to infected organs to beat back the HIV infection.

Details are in the journal PLoS Pathogens.

- here's the release
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