Chemokine receptor CCR5 Delta 32 genetic analysis using multiple specimen types and the NucliSens basic kit

Resistance to HIV-1 infection and delayed disease progression have been ass ociated with a 32-bp deletion (Delta 32) in the gene encoding the CCR5 chem okine receptor. In the present study we describe the modification of a nucl eic acid sequence-based amplification (NASBA)-based CCR5 genotyping assay f or a NucliSens Basic Kit (Organon Teknika, Durham, N.C.) format using a new target-specific sandwich oligonucleotide detection methodology. The new me thod permitted the use of generic electrochemiluminescent probes supplied i n the NucliSens Basic Kit, whereas the original NASBA method required expen sive target-specific ruthenium detection probes. The Basic Kit CCR5 Delta 3 2 genotypic analysis was in 100% concordance with both the original NASBA a ssay and DNA PCR results. This study also evaluated the use of multiple spe cimen types, including peripheral blood mononuclear cells (PBMC), whole blo od, dried blood spots, buccal scrapings, and plasma, for CCR5 genotype anal ysis. The sensitivities of the three assays were comparable when PBMC or wh ole blood was the specimen source. In contrast, when dried blood spots, buc cal scrapings, or plasma was used as the sample source, the sensitivity of DNA PCR was 80.95, 42.8, or 0%, respectively, compared to 100% sensitivity obtained with the original NASBA and Basic Kit NASBA assays. Our study indi cates that the NucliSens Basic Kit NASBA assay is very sensitive and specif ic for CCR5 Delta 32 genotyping using multiple sample types.