Study sheds light on residual viral load

[John2038]

Residual low-level HIV plasma viremia correlates with size of the CD4 T-cell reservoir, but not immune activation markers.

In the present study the researchers assessed plasma viremia using very sensitive tests that could measure down to 0 copies/mL. They tested samples from 127 participants on ART who had undetectable plasma viral load for extended periods, as measured by standard clinical assays (limit of detection of 50 copies/mL). They used an automated system that ran the tests in quadruplicate for each individual.

Results

• 63% of participants with "undetectable" viral load < 50 copies/mL had detectable plasma viremia (1-49 copies/mL) according to the sensitive tests.
• 37% had no measurable plasma HIV RNA.
• The median residual viremia level was 2.7 copies/mL.
• Residual plasma HIV level correlated with the size of the CD4 T-cell viral reservoir, or cells carrying proviral DNA.
• Individuals with undetectable plasma viremia according to the sensitive tests had fewer CD4 cells carrying HIV DNA, on average, than those with detectable plasma viremia.
• Residual plasma viremia did not, however, correlate with markers of immune activation including C-reactive protein, D-dimer, interleukin 6, soluble TNF receptor I, and CD38 expression on CD4 and CD8 T-cells.

These findings, the study authors wrote, suggest that "reactivation of the latent viral reservoir may not be the sole source of residual plasma viremia."

http://www.eatg.org/eatg/Global-HIV-News/Basic-Science/Study-sheds-light-on-residual-viral-load

[coolstone25]

full pdf of the research paper for those interested.

http://www.natap.org/2011/HIV/135full.pdf