Posted on September 17, 2018
"In people living with HIV, antiretroviral therapy (ART) can suppress viral replication, improve overall health and normalize life expectancy. Unfortunately, some people treated with ART after HIV has already significantly damaged the immune system—particularly those with opportunistic infections such as tuberculosis or cytomegalovirus—may develop a serious condition called HIV-associated immune reconstitution syndrome (IRIS). In people with IRIS, the rebounding immune system overcompensates for HIV-associated damage with severe inflammation that can damage tissues and cause symptoms such as high fevers. Now, infectious-disease and radiology researchers from NIAID and the NIH Clinical Center are working together to visualize and predict this common complication of HIV in a new way—with positron emission tomography (PET). The researchers describe their findings in a paper published this week in Clinical Infectious Diseases and in a new NIAID Video SNiP."
"The study began when researchers led by Irini Sereti, M.D., chief of the HIV Pathogenesis Section of the NIAID Laboratory of Immunoregulation, discovered that immune cells reactivated by ART in people with IRIS were more likely to express a cellular receptor called Glut-1. This receptor helps cells take in glucose, the sugar they use to fuel their overactive inflammatory response. Glut-1 also recognizes 18F-Fluorodeoxyglucose (FDG)—a tracer PET molecule used to quantify cellular sugar metabolism. FDG PET scans are commonly used to visualize tumors that require excessive amounts of energy as they increase in size. While Dr. Sereti and her team could track the inflammatory response of IRIS by looking at patient’s blood samples, they wondered if they could also visualize this disease process in action with PET. To help answer that question, they collaborated with Dima A. Hammoud, M.D., a tenure-track investigator and chief of the Hammoud Laboratory at the Center for Infectious Disease Imaging in the NIH Clinical Center."