Research Note: Rapid detection of avian infectious laryngotracheitis virus with real-time fluorescence-based recombinase-aided amplification

作者：Wenjing Wang; Chunguang Wang; Zichuang Zhang; Peng Zhang; Shanshan Yao; Jingru Liu; Xianghe Zhai; Tie Zhang

来源：Poultry Science, 2020.

DOI：10.1016/j.psj.2020.06.025

In this study, specific primers and fluorescent probes were designed to target the thymidine kinase (TK) gene sequence of avian infectious laryngotracheitis virus (ILTV). Through specificity and sensitivity tests, a real-time fluorescence-based recombinase-aided amplification (RF-RAA) method for detecting ILTV was established. The results showed that the method was specific and could be used to accurately detect ILTV, and there was no cross reaction with Newcastle disease virus (NDV), avian influenza virus (AIV) or infectious bronchitis virus (IBV). RF-RAA had high sensitivity, and the lowest detectable limit (LDL) for ILTV could reach 10 copies/μL, 1000 times more sensitive than conventional PCR (104 copies/μL), to rival that of real-time fluorescence-based quantitative PCR (RFQ-PCR) (10 copies/μL). This method and RFQ-PCR were used to detect 96 samples of chicken throat swabs with ILT initially diagnosed in clinic from the north of China, and the coincidence rate of the two methods was 100%. The RF-RAA reaction required only 20-30 minutes to completing, and its sensitivity was much higher than that of conventional PCR. RF-RAA is similar to RFQ-PCR and has the advantages of specificity, sensitivity and high efficiency, so it is suitable for early clinical detection and epidemiological investigation of ILTV.