Defective HIV mutants are not silent

Despite effective antiretroviral therapy, HIV cannot currently be completely eliminated from the body. Viral genetic material remains integrated into the DNA of infected immune cells, particularly CD4 T cells. Most of these proviruses are defective and cannot produce infectious virus, but some remain transcriptionally active.

The study focused on the BACH2 gene, an important regulator of immune-cell development and function. It shows that a defective HIV provirus integrated into this region can disrupt the normal regulation of BACH2, leading to changes in the activity of numerous genes. As a result, infected T cells can acquire properties that promote their survival and proliferation. This may help explain why certain HIV-infected cell clones persist during long-term treatment.

The study further shows that the effects of HIV integration can depend on where the viral DNA is inserted. Importantly, reducing the activity of the defective provirus could mitigate the changes observed at BACH2. These findings highlight that defective HIV sequences are not necessarily passive remnants, but can continue to influence the biology of infected cells.

We are pleased to have contributed to this collaborative work, which adds an important piece to our understanding of HIV persistence and may help inform future strategies aimed at silencing the viral genetic material that remains in the body.

The study can be found here.