AEGiS-12IAC: HIV-1 cellular RNA load arise in late stage of HIV-disease but do not correlate with the proviral sequence variability: cross sectional study representing all stages of infection.

12th International AIDS Conference

Geneva, Switzerland - June 28-July 3, 1998

HIV-1 cellular RNA load arise in late stage of HIV-disease but do not correlate with the proviral sequence variability: cross sectional study representing all stages of infection.

Int Conf AIDS 1998 Jun 28-Jul 3; 12:14 (abstract no. 11158)

Merzouki A, Bouhdoud L, Mandy F, Arella M
Institut Armand Frappier, Laval, Quebec, Canada.

OBJECTIVE: To study the relationship between the ongoing viral replication in PBMCs (measure of the differences in the relative abundance of HIV-1 regulatory and structural mRNAs) of 30 patients at different stages of the infection and the proviral sequence variability.

METHODS: We describe a cross sectional study of multiply spliced (tat, rev, and nef mRNA) and unspliced (gag-pol mRNA) HIV-1 RNA expression using a reverse transcriptase-quantitative, competitive PCR (RT-qcPCR) assay in a cohort of 30 patients (10 in stage II, 10 in stage III and 10 in stage VIC1). We used the nested-PCR to amplify the V3, C4 and C5-C6 env gene regions. Amplicons were cloned and up to 10 from each sample were sequenced. Phylogenetic analysis and calculations of intra- and inter-patient variability were performed by using the software PHYLIP version 3.5.

RESULTS: mRNA quantitation data are expressed as copy number per 1000 PBMC. Patients in stage II showed intermediate levels of RNA expression (between 10 and 300 copies) with a mean ratio of total regulatory to gag-pol mRNAs of 6.2 ± 4.8. Patients in stage III and IVC1 showed a high level of total regulatory mRNA (between 20 and 600 copies) and a rising level of gag-pol mRNA (between 50 and 500 copies) resulting in a 2.3 fold reduction of the mean splicing ratio, from 6.2 ± 4.8 to 2.7 ± 1.4 (stage III) and 2.8 ± 1.7 (stage IVC1). These RNA patterns are unrelated with sequence proviral variability. Both intra-/ and inter-patient V3, C4 and C5-C6 sequences displayed great variability (ranging from 6.1% to 12.5% for the V3, 1.8% to 8.6% for the C4 and 2.0% to 6.8% for the C5-C6 region) irrespective of the degree of infection progression or the ongoing viral replication in PBMCs.

CONCLUSIONS: We showed that the ratio of multiply spliced to unspliced RNA declines by threefold over the course of HIV-1 infection while viral RNA expression in PBMCs of infected individuals have a rise in total viral RNA in late stage HIV-disease. Such rise in unrelated with the level of proviral sequences variability but follows the appearance of variants with predicted SI/T-cell tropic phenotype (rapidly replicating and cytopathic phenotype) that map the V3 region.

Keywords: AEGIS, HIV Infections, HIV-1, RNA, Viral, Cross-Sectional Studies, Virus Replication, RNA, Messenger, Reverse Transcriptase Polymerase Chain Reaction, RNA Splicing, Polymerase Chain Reaction, RNA, DNA Primers, Human, virology, genetics, ICA12
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