Using reliable biomarkers, scientists have found a unique epigenetic footprint which offers them insight into how cognitive impairment in people with human immunodeficiency virus (HIV) develops, claims a study.
The research, published in the journal Nature Scientific Reports, shows specific types of immune cells from blood that can help identify individuals with HIV and how the virus affects cognition in people.
"These results offer the first significant window into the mechanisms driving HIV-related brain damage and how to track the disease. Combination anti-retroviral therapies have improved HIV survival and if started early and taken daily for life, anti-retroviral therapies can result in fewer non-AIDS related complications," said Lishomwa Ndhlovu, Associate Professor at the University of Hawaii at Manoa, in the US.
It has long been suspected that changes in cells of the monocyte or macrophage lineage -- a type of immune cell -- influence the development of cognitive impairment in HIV patients.
Since HIV infection itself alters epigenetic processes in the immune system, the research team wondered whether a distinct DNA methylation profile -- a major epigenetic modification where methyl groups are added to DNA -- occurs in those with HIV associated-cognitive impairment and whether it exists in distinct immune cell populations from the blood.
By evaluating DNA methylation, the researchers discovered differences in gene networks and gene expression linked to the central nervous system and interactions with HIV that appeared uniquely in monocytes of HIV infected study participants with cognitive impairment.
"Strikingly, further analysis showed a strong association between DNA methylation levels of these markers in monocytes and neuropsychological test function, measured using a composite score of multiple cognitive domains," said Alika Maunakea, Assistant Professor at the University of Hawaii at Manoa.
According to researchers, the field of epigenetics has ushered in a new era of discovery in immunology and neuroscience.
"The advancement in epigenetic therapeutics also affords promising new interventions that should be considered for the management of HIV associated cognitive impairment, provided they are selective to the appropriate immune cell target," Ndhlovu added.