Cassol S, Gill M J, Pilon R, Cormier M, Voigt R F, Willoughby B, Forbes J
Ottawa General Hospital Research Institute and the University of Ottawa, Ontario, Canada.
J Clin Microbiol. 1997 Nov;35(11):2795-801. doi: 10.1128/jcm.35.11.2795-2801.1997.
To assess dried plasma spots (DPSs) as a source of material for virus quantification, human immunodeficiency virus type 1 (HIV-1) RNA levels were quantified in matched DPS and liquid plasma samples from 73 infected patients, including 5 neonates and 4 adult patients with acute HIV-1 infection. Quantifications were performed by commercially available assays (NASBA [nucleic acid sequence-based amplification] or Amplicor, or both). There was a strong correlation between HIV-1 RNA levels in plasma and DPSs. More importantly, there was no decline in HIV-1 RNA levels in DPSs stored for as long as 2 weeks at 20 degrees C. Similarly, storage of DPSs for 3 days at 37 degrees C resulted in no decrease in viral RNA levels. For patients with primary infection, the DPS method allowed for the measurement of RNA levels in plasma during the initial spike in the level of viremia and in the subsequent period of suppressed viral replication. DPS quantification was equally informative in the neonatal setting, with all five newborns showing HIV-1 RNA loads of greater than 4.991 log10 copies/ml. We conclude that the viral RNA levels in DPSs are equivalent to those measured in fresh-frozen plasma. The ease and economy of DPS sampling, the minute volumes required, and the unexpected stability of dried RNA suggest that the use of DPSs will be particularly valuable for small-volume neonatal samples and large, population-based studies in which cold storage and transportation present special problems, as is often the case in developing countries. The ability to measure viral changes during primary infection suggests that the method will be useful for assessing vaccine efficacy in large field trials.
为评估干血浆斑（DPS）作为病毒定量材料来源的情况，对73例感染患者（包括5例新生儿和4例急性人类免疫缺陷病毒1型（HIV-1）感染的成年患者）匹配的DPS和液体血浆样本中的HIV-1 RNA水平进行了定量。定量通过市售检测方法（基于核酸序列的扩增技术（NASBA）或Amplicor，或两者同时使用）进行。血浆和DPS中的HIV-1 RNA水平之间存在很强的相关性。更重要的是，在20摄氏度下保存长达2周的DPS中，HIV-1 RNA水平没有下降。同样，在37摄氏度下将DPS保存3天，病毒RNA水平也没有降低。对于原发性感染患者，DPS方法能够在病毒血症水平最初激增期间以及随后病毒复制受到抑制的时期测量血浆中的RNA水平。在新生儿中，DPS定量同样具有参考价值，所有5名新生儿的HIV-1 RNA载量均大于4.991 log10拷贝/毫升。我们得出结论，DPS中的病毒RNA水平与新鲜冷冻血浆中测得的水平相当。DPS采样的简便性和经济性、所需的微量体积以及干燥RNA出人意料的稳定性表明，对于小体积新生儿样本以及大规模基于人群的研究（在发展中国家通常会遇到冷藏和运输方面的特殊问题），使用DPS将特别有价值。在原发性感染期间测量病毒变化的能力表明，该方法将有助于在大型现场试验中评估疫苗效力。
