Affiliations : *National Institute of Health, Deparment of Medical Sciences,
**Department of Biotechnology, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand
Source: Southeast Asian Journal of Tropical Medicine and Public Health 2003; 34(3): 221-226
A protocol for detecting HIV DNA from specimens collected on filter papers and the effect of storage temperatures on determination of HIV DNA from dried blood spots has been developed and optimized. Blood specimens collected from HIV- 1 infected and normal persons were spotted onto blood collection cards (Whatman BFC 180). The HIV DNA was extracted by phenol-chloroform-isoamyl alcohol and was detected for C2V4 of HIV- 1 env by nested polymerase chain reaction (nested PCR ). One set was stored at -20°C for 14 weeks, another at 37°C for 1 week and then kept at -20°C for 13 weeks and a third set at 25°C for 1 week and then -20°C for 13 weeks. The dried blood spots from each set were detected for the HIV DNA every 2 weeks for 14 weeks. The C2V4 region of HIV env DNA was determined from small amounts of the dried blood collected on the filter papers. The nested PCR procedure could detect as few as 5 copies of HIV proviral DNA , and HIV DNA could be detected from specimens with viral loads of 2×104 copies/ml . HIV DNA could be detected from specimens collected at all temperatures tested for at least 14 weeks. Therefore, laboratory diagnosis of HIV infection can be done by PCR on dired blood spots. These techniques will be useful as a tool for studying the epidemiology of HIV infection among population of interest such as mother to child infection using newborn screening specimens.