Dengue is a major global health threat, and there are no approved antiviral agents. Prior research using Cas13 only demonstrated dengue mitigation in vitro. Here we demonstrate that systemic delivery of mRNA-encoded Cas13a and guide RNAs formulated in lipid nanoparticles can be used to treat dengue virus (DENV) 2 and 3 in mice. First, we identified guides against DENV 2 and 3 that demonstrated in vitro efficacy. Next, we confirmed that Cas13 enzymatic activity is necessary for DENV 2 or DENV 3 mitigation in vitro. Last, we show that a single dose of lipid-nanoparticle-formulated mRNA-encoded Cas13a and guide RNA, administered 1 day post-infection, promotes survival of all infected animals and serum viral titre decreases on days 2 and 3 post-infection after lethal challenge in mice. Off-target analysis in mice using RNA sequencing showed no collateral cleavage. Overall, these data demonstrate the potential of mRNA-encoded Cas13 as a pan-DENV drug.

登革热是全球主要的健康威胁，目前还没有批准的抗病毒药物。之前使用 Cas13 的研究仅证明了体外登革热缓解。在这里，我们证明了脂质纳米颗粒中配制的 mRNA 编码的 Cas13a 和引导 RNA 的全身递送可用于治疗小鼠中的登革热病毒 (DENV) 2 和 3。首先，我们确定了针对 DENV 2 和 3 的指导，并证明了其体外功效。接下来，我们证实 Cas13 酶活性对于体外缓解 DENV 2 或 DENV 3 是必需的。最后，我们表明，感染后 1 天施用单剂量的脂质纳米颗粒配制的 mRNA 编码的 Cas13a 和引导 RNA，可促进所有感染动物的存活，并且致死后感染后第 2 天和第 3 天血清病毒滴度下降对小鼠的挑战。使用 RNA 测序对小鼠进行脱靶分析显示没有附带裂解。总的来说，这些数据证明了 mRNA 编码的 Cas13 作为泛 DENV 药物的潜力。