ABSTRACT
PURPOSE: We have developed a sequencing assay for determining the usage of the genotypic HIV-1 co-receptor using peripheral blood mononuclear cell (PBMC) DNA in virologically suppressed HIV-1 infected patients. Our specific aims were to (1) evaluate the efficiency of V3 sequences in B versus non-B subtypes, (2) compare the efficiency of V3 sequences and tropism prediction using whole blood and PBMCs for DNA extraction, (3) compare the efficiency of V3 sequences and tropism prediction using a single versus a triplicate round of amplification. RESULTS: The overall rate of successful V3 sequences ranged from 100 % in samples with >3,000 copies HIV-1 DNA/10(6) PBMCs to 60 % in samples with <100 copies total HIV-1 DNA /10(6) PBMCs. Analysis of 143 paired PBMCs and whole-blood samples showed successful V3 sequences rates of 77.6 % for PBMCs and 83.9 % for whole blood. These rates are in agreement with the tropism prediction obtained using the geno2pheno co-receptor algorithm, namely, 92.1 % with a false-positive rate (FPR) of 10 or 20 % and of 96.5 % with an FPR of 5.75 %. The agreement between tropism prediction values using single versus triplicate amplification was 98.2 % (56/57) of patients using an FPR of 20 % and 92.9 % (53/57) using an FPR of 10 or 5.75 %. For 63.0 % (36/57) of patients, the FPR obtained via the single amplification procedure was superimposable to all three FPRs obtained by triplicate amplification. CONCLUSIONS: Our results show the feasibility and consistency of genotypic testing on HIV-1 DNA tropism, supporting its possible use for selecting patients with suppressed plasma HIV-1 RNA as candidates for CCR5-antagonist treatment. The high agreement between tropism prediction by single and triple amplification does not support the use of triplicate amplification in clinical practice.
Subject(s)
Genotyping Techniques/methods , HIV Infections/virology , HIV-1/genetics , HIV-1/physiology , Molecular Diagnostic Techniques/methods , Receptors, HIV/metabolism , Viral Tropism , Adult , DNA, Viral/chemistry , DNA, Viral/genetics , DNA, Viral/isolation & purification , Female , HIV Infections/diagnosis , HIV-1/classification , HIV-1/isolation & purification , Humans , Male , Middle Aged , Proviruses/classification , Proviruses/genetics , Proviruses/isolation & purification , Sequence Analysis, DNA , Virus InternalizationSubject(s)
Drug Resistance, Viral/genetics , HIV Infections/virology , HIV-1/genetics , Infectious Disease Transmission, Vertical , Adolescent , Adult , Anti-HIV Agents/therapeutic use , Female , HIV Infections/drug therapy , HIV Infections/epidemiology , HIV Infections/transmission , HIV-1/drug effects , Humans , Italy/epidemiology , Male , Mutation , Prevalence , Retrospective Studies , Young Adult , pol Gene Products, Human Immunodeficiency Virus/geneticsABSTRACT
The isolation of Mycobacterium malmoense has for a long time been restricted to few countries of Northern Europe; reports from countries other than Sweden, Great Britain and Finland are rare and the first Italian case report has been published in 1995. Since 1988, however, fifteen strains of M. malmoense have been isolated in Italy, eleven of which in the last two years; of these, ten appeared clinically significant on the basis of medical records. The susceptibility of the strains and the role of high performance liquid chromatography of cell wall mycolic acids for a reliable identification are discussed.