Immune Receptor May Be Key to Treating HIV-related Complications

Although current treatments can keep HIV under control, many individuals still face disease-related complications such as neurocognitive disorders, cardiovascular issues, diabetes, and chronic inflammation.

In a new study published in the Journal of Immunology, researchers aimed to determined why some individuals with HIV experience persistent immune activation that can lead to more complications. Their findings pointed to an immune receptor called SLAMF7.

For the study, researchers from Michigan State University examined both healthy individuals and patients with HIV. They discovered that in patients with HIV-related complications, their immune receptors were malfunctioning, leading to a chronic proinflammatory state.

According to the study, the receptor SLAMF7 was found to tone down the body’s immune response when activated on certain white blood cells, called monocytes. Additionally, the researchers found that SLAMF7 activation on monocytes can decrease susceptibility to HIV infection by increasing the level of a protein, CCL3L1, which makes it harder for the virus to get inside cells.

The researchers tested the blood of the study participants, isolated their white blood cells and stimulated them with interferon alpha, a protein that activates the immune system’s response to infections. They found that the SLAMF7 receptor was unresponsive in certain patients with HIV who had more complications and often had worse prognosis.

“SLAMF7 can act like a seesaw and keep the balance of the immune system in check,” Patrick O’Connell, a 4-year doctoral student who led the project with Yassar Aldhamen, said in a press release. “When receptors need to turn immune cells on because of an infection, they bind to the cells and work with fellow receptors to activate the immune system. When signs of the infection or inflammation go away, the receptors switch gears and turn off the immune response.”

The researchers noted that understanding the molecular mechanism of the SLAMF7 receptor and how it works could lead to new drug treatments that target immune activation. Although most HIV drugs target the virus itself, the researchers indicated that developing a therapy that modifies the immune system could be another approach to fighting the virus.

The study was funded by the National Institutes of Health.

Reference

Faulty Immune Receptor Could Be Reason Why Many Face HIV Complications [news release]. Michigan State University’s website. https://msutoday.msu.edu/news/2019/faulty-immune-receptor-could-be-reason-why-many-face-hiv-complications/. Accessed January 7, 2019.