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Issue No. 29 | July 6, 2007

News and Features

Summer 2007 Issue of Mental Health AIDS Released

Biopsychosocial therapy involves assessing an individual patient's biological, psychological, and social condition to help determine the best treatment for them.

Mental Health AIDS is a quarterly biopsychosocial research update on HIV and mental health sponsored by the Center for Mental Health Services (CMHS) of the Substance Abuse and Mental Health Services Administration (SAMHSA). This publication is provided free of charge through the SAMHSA Web site in both PDF and HTML formats.

The Summer 2007 issue features the Tailoring Evidence-Based HIV Behavioral Risk-Reduction Interventions to Local Capacity & Target Audience Characteristics Tool Box. Guidance about modifying an evidence-based behavioral intervention is discussed in this tool box.  In addition, examples of modified interventions to reduce HIV incidence rates are provided. 

Researchers Discover an Enzyme that Removes HIV-1 DNA from Infected Cells

In recent years, therapies to combat HIV/AIDS have drastically improved. HIV infection is now considered a chronic illness which therapies such as highly active antiretroviral therapy (HAART) can successfully manage. HAART, however, only suppresses the HIV life cycle; it does not eliminate the infection. Furthermore, new, drug-resistant strains of HIV-1 are constantly appearing, making the need for better treatment options even more urgent.

HIV reverse transcribes its RNA genome into DNA and then inserts it into the DNA of the infected cell. Reverse transcriptase inhibitors (NRTIs, NNRTIs) and integrase inhibitors interfere with these events in the HIV life cycle. Unfortunately, there are no treatments that can remove the HIV-1 DNA once it has been inserted, which means the cell will remain infected forever.

Recently, however, a group of researchers at the Max-Planck-Institute for Molecular Cell Biology and Genetics in Dresden, Germany, have discovered a way to remove the HIV-1 DNA from infected cells. This would effectively "cure" the cells and make them unable to produce more virus.

The researchers developed a DNA recombinase (an enzyme that breaks and recombines DNA) that targets HIV-1 DNA in the genome of a host cell and removes it. The researchers directed the "evolution" of 50 individual recombinases in performing this function in E. coli. They named the most active recombinase that resulted from this process "Tre" and tested its efficacy in mammalian cells and then in human cells. Tre was successful in removing the HIV-1 DNA from all cell types tested.

Although Tre offers promise for the future of HIV treatment, it will be many years before it is ready to be used as a therapy in humans. Researchers have not yet determined how the enzyme would be administered to patients or what kind of adverse events it may produce.

For more information about currently available treatments for HIV, please refer to the AIDSinfo fact sheet on HIV and its Treatment.