Proviral HIV-1 dynamics and evolution in patients receiving efficient long-term antiretroviral combination therapy.
OBJECTIVE
Different experimental approaches have shown that, despite plasma viral loads under the threshold of detection, HIV-1 frequently continues to replicate in patients receiving potent antiretroviral therapy. However, whether this low-grade viral replication is sufficient for the generation of new major quasispecies has not been studied. Thus, in order to evaluate the extent of variation in the major proviral HIV-1 population, we monitored proviral DNA sequences in such patients over a time period of up to 30 months.


METHODS
DNA was extracted from peripheral blood mononuclear cells (PBMC) and the V3 region was amplified by nested polymerase chain reaction (PCR) and directly sequenced. Additionally, both HIV-1 RNA and DNA levels and CD4+ T-lymphocyte counts were monitored.


RESULTS
Analysing the V3 gene sequences of 17 patients, we observed a sequence evolution in nine patients. Interestingly, the majority of these changes (77%) occurred in the first interval following the initiation of therapy and despite signs of ongoing replication the proviral DNA levels continued to decrease in all patients.


CONCLUSIONS
Our data suggest that, although available data report that HIV-1 continues to replicate in patients with undetectable viraemia, the extent of viral replication in many of these patients is not sufficient to result in changes in the major viral population.
Birk
M
M
Divisions of Clinical Virology and Infectious Diseases, Karolinska Institute, Huddinge University Hospital, Sweden. markus.birk@impi.ki.se
Aleman
S
S
Visco-Comandini
U
U
Sönnerborg
A
A
D000328:Adult; D000595:Amino Acid Sequence; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D017931:DNA Primers; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy* / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000032:analysis; D013997:Time Factors; D016896:Treatment Outcome
D017931:DNA Primers; D004279:DNA, Viral; D012367:RNA, Viral