HIV Cure Research Takes a Step Forward

Macrophages found to be a clear source of replicating HIV.

A recent study found that macrophage-tropic strains of HIV infect and reproduce in macrophages, showing promise for the research and development of an HIV cure.

HIV macrophages, which are myeloid lineage cells, ingest foreign material. In prior studies, it was concluded that macrophages become infected once they ingest compromised CD4 T cells.

For the current study, published in the Journal of Clinical Investigation, investigators used a humanized myeloid-only mouse model (MoM), to determine if tissue macrophages are productively infected with HIV.

“This study unequivocally demonstrates macrophages are a clear source of replicating virus,” said study co-author, Joseph Eron, MD.

The results of the study showed that macrophages were able to sustain HIV replication even in the absence of T cells; macrophages infected with HIV are distributed in various tissues, including the brain; replication-competent virus can be rescued from infected macrophages obtained from tissues of MoM; and HIV-infected macrophages have the ability to establish infection in new hosts.

“If the T cells were the only target of HIV cure research, eradicating the virus would still be tough,” added study co-author, J. Victor Garcia, PhD. “Now we have demonstrated that there is another cell target where replicating HIV can be found, which could make eradicating the virus from the host and finding a cure for HIV/AIDS harder.”

The next step in the process will be to introduce antiretroviral therapy into the models and to determine if the virus will continue to replicate despite the treatment.

“This model will allow us to ask the critical question as to whether or not macrophages represent a latent reservoir for HIV after treatment with antiretroviral therapy,” said lead author of study Jenna Bone Honeycutt, PhD. “These experiments will inform the future direction of HIV cure research as we know it.”