446   Drug-Selected HIV-1 Mutations Can Differ in Cervico- Vaginal and Blood Plasma RNA.

M. P. De Pasquale*¹, J. Allega², L. Sutton¹, R. T. D'Aquila¹, A. C. Caliendo², S. Donahue³, and S. Cu-Uvin³.
¹Massachusetts Gen. Hosp. and Harvard Univ., Boston;²Emory Univ. Hosp., Atlanta, GA; and³Brown Univ., Providence, RI.

Background:There are limited data on whether the female genital tract may be a compartment for replication of drug-selected HIV-1 genotypes different from those which dominate at the same time in blood plasma RNA, as has been frequently noted for semen.

Methods:Seven HIV(⁺)women on failing ART and 3 HIV(⁺)untreated women were studied. Each had detectable viral load in plasma and cervico-vaginal lavage (CVL) or endocervical secretions collected by Sno- strips (Nuclisens). RNA extracted (Qiagen) from plasma and either CVL or Sno-strips was subjected to RT-PCR. Population sequence was determined with standard HIV pol cycle sequencing kits (9 VGI, 1 ABI). HIV DNA from cells centrifuged from CVL was also sequenced from 3 of the treated patients' specimens.

Results:Five of the 7 women on a failing antiretroviral regimen had drug-selected mutations in cervico-vaginal RNA which were not detected in plasma, including mutations in PR (46I, 54V, 82A, 84V, 90M) and RT (184V). Other sequence differences were also seen between plasma and CVL. One CVL sequence was quite diverse and diverged markedly from the corresponding plasma sequence. Two of the 7 women failing therapy had the same genotype in plasma and genital secretions, 1 with multiple PR and RT mutations in both fluids and 1 with no mutations in either fluid. CVL cell DNA sequences reflected a pre-drug-exposed virus compared to CVL RNA in 2 of 3 ART failures. In contrast, sequences from each of 3 drug-naïve women's plasma and CVL did not differ in any drug-selected positions; polymorphisms and silent mutations at other positions were also similar.

Conclusions:Drug-selected mutations in cervico-vaginal secretions can differ from those dominant in blood during ART failure. Further studies are needed to define implications for vertical or heterosexual transmission of resistant virus.