AUTHOR=Wang Yonglu , He Ziqiang , Ablimit Patigul , Ji Shunshi , Jin Dong 

TITLE=Development of multiplex cross displacement amplification combined with lateral flow biosensor assay for detection of virulent shigella sonnei

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.1012105

DOI=10.3389/fcimb.2022.1012105

ISSN=2235-2988

ABSTRACT=<p><italic>Shigella sonnei</italic> is the most common <italic>Shigella</italic> spp. in developed areas and the second most common in undeveloped regions. In this study, a multiple cross displacement amplification (MCDA) assay was used in combination with a lateral flow biosensor (LFB) assay to detect virulent <italic>S. sonnei</italic> strains containing the <italic>ipaH</italic> and <italic>wbgX</italic> genes. The multiplex MCDA-LFB assay detected <italic>wbgX</italic> at ≥1 pg/μL and <italic>ipaH</italic> at ≥10 fg/μL within 30 min in pure cultures maintained at 63°C. This assay was sensitive for ~37 CFU of virulent <italic>S. sonnei</italic> and ~3.7 CFU of <italic>Shigella</italic> spp. and enteroinvasive <italic>E. coli</italic> in stimulated fecal samples and had 100% specificity among 59 reference strains. The MCDA-LFB assay was also able to differentiate between virulent <italic>S. sonnei</italic> and other <italic>Shigella</italic> spp. and enteroinvasive <italic>E. coli</italic> among 99 clinical isolates. In summary, a multiplex MCDA-LFB assay was developed for rapid, convenient, point-of-care, and accurate identification of virulent <italic>S. sonnei</italic> within 30 min and at a constant temperature without the need for expensive lab equipment.</p>