Latent HIV reservoir unlikely to ever completely disappear
natap.org
Last Updated: 2003-06-06 14:45:38 -0400 (Reuters Health)
By Anthony J. Brown, MD
NEW YORK (Reuters Health) - Findings from a new study confirm that even with persistent undetectable serum viral levels, latent HIV infection in resting memory CD4+ T cells is likely to persist forever in most patients.
"The findings suggest that by inhibiting different steps in the virus life cycle, we are never going to cure anybody," senior author Dr. Robert F. Siliciano, from Johns Hopkins University in Baltimore, told Reuters Health. "We may be able to keep them disease free for life, which is great, but I think it's unlikely that the infection will be cured ever."
In 1999, Dr. Siliciano's team showed that the latent reservoir of infected memory cells decays very slowly with a half-life of at least 43 months (see Reuters Health report April 27, 1999).
The current study expands on the previous one by including nearly twice as many patients (62) and by having a longer follow-up period, in some cases up to 7 years. The results are published in the May 19th advance online issue of Nature Medicine.
"The 1999 study included only 3 years of follow-up and there was also some controversy regarding the effect of viremia blips on decay of the reservoir," Dr. Siliciano said. "So, in the current study, we included patients with and without blips."
Despite the differences between the two studies, the current findings are nearly identical to those previously reported. The average half-life of the latent reservoir was 44.2 months.
"At that rate, assuming a million infected cells in the body, it would take about 70 years for them to decay," Dr. Siliciano noted. "Basically, this means that this reservoir is never going to go away."
Although patients without blips experienced faster reservoir decay than patients with blips, the difference was not significant, the investigators note.
Dr. Siliciano admitted that the present results are discouraging. Still, he emphasized that there is good evidence that long-term control of HIV infection can be achieved with HAART.
Nat Med 2003;May 19th advance online issue:000-000. |
