The goal of this research project is to develop a nucleic acid hybridization assay for HTLV-III/ LAV viral DNA and mRNA which can be completed within two hours, has minimal biohazard associated with performing the test, and is appropriate for automation. The probe assay will be tested for sensitivity and accuracy by comparison to viral culture assays which are at present required for viral detection and quantitation.Parameters of sample preparation (especially the use of chaotropes, hydrogen-bondbreaking solvents, and detergents), probe construction, hybrid isolation, noise reduction, and data analysis will be optimized to develop an assay which can quantitate viral nucleic acids in blood and tissue samples without culture. Conditions will be evaluated to improve the ease and sensitivity of the assay. Inclusion of machine components and shortening the duration of the assay will facilitate commercialization of the new technologies.These technologies can provide a quick and economical diagnositic test suitable for detecting viral nucleic acids and assaying expression of viral message as an indicator of viral physiology.National Cancer Institute (NCI)