The recent extensive spread of Zika virus has led to increased interest in the development of early diagnostic tests. To the best of our knowledge, this is the first study to demonstrate the successful use of phage display to identify affinity peptides for quantitative analysis of AXL, a tyrosine kinase receptor involved in Zika virus entry. Biopanning of M13 phage library successfully identified a high affinity peptide, with the sequence AHNHTPIKQKYL. To study the feasibility of using free peptides for molecular recognition, we synthesized a series of amino acid-substituted peptides and examined their binding affinity for AXL using electrochemical impedance spectroscopy and square wave voltammetry. Most synthetic peptides had non-identical random coil structures based on circular dichroism spectroscopy. Of the peptides tested, AXL BP1 exhibited nanomolar binding affinity for AXL. To verify whether AXL BP1 could be used as a peptide inhibitor at the cellular level, two functional tests were carried out: a WST assay for cell viability and qRT-PCR for quantification of RNA levels in Zika virus-infected Huh7 cells. The results showed that AXL BP1 had low cytotoxicity and could block Zika virus entry. These results indicate that newly identified affinity peptides could potentially be used for the development of Zika virus entry inhibitors.

寨卡病毒最近的广泛传播导致人们对开发早期诊断测试的兴趣增加。据我们所知，这是第一项证明噬菌体展示成功用于鉴定亲和性肽以定量分析AKA（一种参与寨卡病毒进入的酪氨酸激酶受体）的定量分析的研究。M13噬菌体文库的生物淘选成功鉴定出了具有序列AHNHTPIKQKYL的高亲和力肽。为了研究使用游离肽进行分子识别的可行性，我们合成了一系列氨基酸取代的肽，并使用电化学阻抗谱和方波伏安法检查了它们对AXL的结合亲和力。大多数合成肽基于圆二色性光谱具有不同的随机线圈结构。在测试的肽中，AXL BP1对AXL表现出纳摩尔结合亲和力。为了验证AXL BP1是否可以在细胞水平上用作肽抑制剂，进行了两项功能测试：用于细胞生存力的WST分析和用于定量寨卡病毒感染的Huh7细胞中RNA水平的定量qRT-PCR。结果表明，AXL BP1细胞毒性低，可以阻止寨卡病毒进入。这些结果表明，新近鉴定的亲和力肽可以潜在地用于寨卡病毒进入抑制剂的开发。结果表明，AXL BP1细胞毒性低，可以阻止寨卡病毒进入。这些结果表明，新近鉴定的亲和力肽可以潜在地用于寨卡病毒进入抑制剂的开发。结果表明，AXL BP1细胞毒性低，可以阻止寨卡病毒进入。这些结果表明，新近鉴定的亲和力肽可以潜在地用于寨卡病毒进入抑制剂的开发。