Delivering a death blow to HIV

Antiretroviral drugs, though effective in suppressing an HIV infection, do not completely eradicate the disease. Instead, the virus acquires “escape mutations” that allow it to evade an attack by cytotoxic T lymphocytes (CTLs), the body’s virus-specific immune mechanism, and becomes latent in CD4+ T lymphocytes.

New research by Yale scientists suggests that programming CTLs to recognize and kill the infected T cells holds promise for developing a cure for HIV. In the journal Nature on Jan. 7, Richard A. Flavell, Ph.D., chair and Sterling Professor of Immunobiology, and colleagues reported that boosting CTL response might hold the key to virus eradication.

The scientists identified CTLs that target unmutated regions of HIV and demonstrated in “humanized” mice harboring an HIV patient’s immune system that these CTLs were able not only to control infection, but also to clear the circulating virus. The study is the first to show that broadly reactive CTLs are effective against latent HIV.

“We reconstructed a human patient in a mouse and demonstrated that the body’s natural defense, when boosted, can clear HIV infection,” says Priti Kumar, Ph.D., assistant professor of medicine and microbial pathogenesis and a co-author of the paper. “A finding like this gives the research field a new direction.”