Transplantation Virology, Institute for Medical Microbiology, Department of Biomedicine, University of Basel, Petersplatz 10, Basel, Switzerland.
Antimicrob Agents Chemother. 2010 Nov;54(11):4714-22. doi: 10.1128/AAC.00974-10. Epub 2010 Aug 16.
Antiviral drugs for treating polyomavirus BK (BKV) replication in polyomavirus-associated nephropathy or hemorrhagic cystitis are of considerable clinical interest. Unlike cidofovir, the lipid conjugate 1-O-hexadecyloxypropyl cidofovir (CMX001) is orally available and has not caused detectable nephrotoxicity in rodent models or human studies to date. Primary human renal proximal tubular epithelial cells were infected with BKV-Dunlop, and CMX001 was added 2 h postinfection (hpi). The intracellular and extracellular BKV DNA load was determined by quantitative PCR. Viral gene expression was examined by quantitative reverse transcription-PCR, Western blotting, and immunofluorescence microscopy. We also examined host cell viability, proliferation, metabolic activity, and DNA replication. The titration of CMX001 identified 0.31 μM as the 90% effective concentration (EC(90)) for reducing the extracellular BKV load at 72 hpi. BKV large T antigen mRNA and protein expression was unaffected at 24 hpi, but the intracellular BKV genome was reduced by 90% at 48 hpi. Late gene expression was reduced by 70 and 90% at 48 and 72 hpi, respectively. Comparisons of CMX001 and cidofovir EC(90)s from 24 to 96 hpi demonstrated that CMX001 had a more rapid and enduring effect on BKV DNA and infectious progeny at 96 hpi than cidofovir. CMX001 at 0.31 μM had little effect on overall cell metabolism but reduced bromodeoxyuridine incorporation and host cell proliferation by 20 to 30%, while BKV infection increased cell proliferation in both rapidly dividing and near-confluent cultures. We conclude that CMX001 inhibits BKV replication with a longer-lasting effect than cidofovir at 400× lower levels, with fewer side effects on relevant host cells in vitro.
抗病毒药物治疗多瘤病毒 BK（BKV）复制与多瘤病毒相关肾病或出血性膀胱炎具有重要的临床意义。与更昔洛韦不同，脂结合物 1-O-十六烷基氧基丙基更昔洛韦（CMX001）可口服给药，迄今为止，在啮齿动物模型或人类研究中未引起可检测的肾毒性。原代人肾近端小管上皮细胞感染 BKV-Dunlop，在感染后 2 小时（hpi）加入 CMX001。通过定量 PCR 测定细胞内和细胞外 BKV DNA 载量。通过定量逆转录-PCR、Western blot 和免疫荧光显微镜检查病毒基因表达。我们还检查了宿主细胞活力、增殖、代谢活性和 DNA 复制。CMX001 的滴定确定 0.31 μM 为在 72 hpi 时降低细胞外 BKV 载量的 90%有效浓度（EC（90））。24 hpi 时 BKV 大 T 抗原 mRNA 和蛋白表达不受影响，但 48 hpi 时细胞内 BKV 基因组减少 90%。晚期基因表达分别在 48 和 72 hpi 时减少 70%和 90%。CMX001 和更昔洛韦的 EC（90）比较从 24 至 96 hpi 表明，与更昔洛韦相比，CMX001 在 96 hpi 时对 BKV DNA 和感染性后代具有更快和更持久的作用。0.31 μM 的 CMX001 对总体细胞代谢影响不大，但将溴脱氧尿苷掺入和宿主细胞增殖减少 20%至 30%，而 BKV 感染增加了快速分裂和接近汇合培养物中细胞的增殖。我们的结论是，CMX001 抑制 BKV 复制的作用比更昔洛韦更持久，在低 400 倍水平下，对体外相关宿主细胞的副作用更少。
