PET-based imaging of HIV anatomical reservoir locations for health monitoring and determination of therapy effectiveness.
- The only in vivo method for visualizing sites of HIV.
- Compatible with existing PET/CT imaging system.
AIDS is a worldwide pandemic, with over 35 million people carrying active HIV infections. The first line of therapy is administering anti-HIV drug cocktails to slow the progression of the disease; however, retroviruses quickly adapt to the regime and become resistant. With over 30% patients resistant to conventional drugs, an aggressive treatment strategy warrants continuous monitoring. Currently, drug treatment success is assessed by measuring HIV levels in blood plasma. This method only identifies actively replicating viruses without identification of the anatomical sites for the virus replication. In addition, during therapy, residual viral replication is suspected and dormant cells carry latent HIV, which will readily reactivate upon cessation of therapy. Present therapies on the market rely on the active replication to suppress a viral infection and are not capable of completely eliminating the virus. Developing methods to visualize viruses can improve choice of therapies offered to HIV/AIDS patients and promote development of therapeutics targeting latent infection.
The HIV particle surrounds its genetic information with a viral envelope that is decorated with proteins. The viral coat proteins communicate with a host cell to gain entry and produce new copies of the virus. Upon infection, the virus deposits membrane proteins like gp120 onto the host cell surface. Researchers at Emory/GA Tech have taken advantage of the coat protein gp120 to detect the location of HIV within host cells. Combined positron emission tomography (PET) and computer tomography (CT) is used to visualize a radiolabelled gp120 antibody that recognizes HIV virions and infected cells. This method provides unprecedented whole body views of viral replication, detection of reservoirs of residual replication during therapy, viral resurgence, and response to antiviral treatments with high sensitivity. Clinical implementation of this technology will provide potential therapeutic and vaccine monitoring opportunities.
Proof of concept study has been conducted with non-human primates.