Development and validation of a multienzyme isothermal rapid amplification and lateral flow dipstick combination
Miaomiao Li1, Mengjiao Lin1, Yushan Xu1
1Department of Blood Transfusion, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China.
Background:
Human T-cell lymphotropic virus-1(HTLV-1) infection may lead to adult T-cell leukemia, HTLV-associated myelopathy/tropical spastic paraplegia, and various neurological diseases. Therefore, developing a rapid and accurate detecting method is crucial for preventing and controlling HTLV-1 infection. This study aims to develop and validate a detection assay for HTLV-1 proviral DNA by combining multienzyme isothermal rapid amplification(MIRA) and lateral flow dipstick(LFD) techniques.
Methods:
Primers and probes were designed based on the conserved sequence of the HTLV-1 Tax gene, and the MIRA-LFD method was established and optimized. Different concentrations of HTLV-1 plasmids were tested by the MIRA-LFD assay to verify the limit of detection(LOD) of the method. To evaluate the cross-reactivity, viral pathogens were detected by this assay, including hepatitis B virus(HBV), hepatitis C virus(HCV), hepatitis E virus(HEV), cytomegalovirus(CMV), herpes simplex virus-1/2(HSV-1/2), Epstein-Barr virus(EBV), Parvovirus B19(B19V), and human T-cell lymphotropic virus-2(HTLV-2). 500 clinical samples were simultaneously detected using real-time PCR(qPCR) and MIRA-LFD methods, and the consistency between the two methods was statistically analyzed. The qPCR was used as the reference method to determine the diagnostic sensitivity and specificity of the MIRA-LFD method.
Results:
The MIRA-LFD method can detect HTLV-1 within 20 min at 37℃. The LOD for HTLV-1 using this method was 200 copies/µL. This method had no cross-reaction with the other eight viruses, with good specificity. Using qPCR as the standard, the diagnostic sensitivity and specificity of the MIRA-LFD method for 500 clinical samples were 100%. The MIRA-LFD and qPCR methods had 100% consistency(kappa value = 1.00).
Conclusions:
This study established a method based on MIRA-LFD for detecting HTLV-1 proviral DNA, which has the advantages of fast, accurate, good sensitivity, strong specificity, simplicity, and portability. This method meet the needs of rapid on-site detection and is easy to promote and use in grassroots medical institutions or blood stations.
