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Updated: Aug 8, 2026
Multiplexed Isothermal Amplification Based Diagnostic Platform to Detect Zika, Chikungunya, and Dengue 1
Published on: March 13, 2018
Development of multiplex cross displacement amplification combined with lateral flow biosensor assay for detection of
Yonglu Wang1,2, Ziqiang He3, Patigul Ablimit2
1Ma'anshan Center for Disease Control and Prevention, Ma'anshan, China.
Abstract:
Shigella sonnei is the most common Shigella 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 S. sonnei strains containing the ipaH and wbgX genes. The multiplex MCDA-LFB assay detected wbgX at ≥1 pg/μL and ipaH at ≥10 fg/μL within 30 min in pure cultures maintained at 63°C. This assay was sensitive for ~37 CFU of virulent S. sonnei and ~3.7 CFU of Shigella spp. and enteroinvasive E. coli in stimulated fecal samples and had 100% specificity among 59 reference strains. The MCDA-LFB assay was also able to differentiate between virulent S. sonnei and other Shigella spp. and enteroinvasive E. coli among 99 clinical isolates. In summary, a multiplex MCDA-LFB assay was developed for rapid, convenient, point-of-care, and accurate identification of virulent S. sonnei within 30 min and at a constant temperature without the need for expensive lab equipment.
Insights
A new multiplex multiple cross displacement amplification (MCDA) assay with a lateral flow biosensor (LFB) rapidly detects virulent Shigella sonnei. This point-of-care test identifies specific genes in under 30 minutes without complex equipment.
Area of Science:
- Microbiology
- Molecular Diagnostics
- Public Health
Background:
- Shigella sonnei is a leading cause of bacterial dysentery globally.
- Accurate and rapid detection of virulent S. sonnei is crucial for effective treatment and outbreak control.
Purpose of the Study:
- To develop a rapid, sensitive, and specific diagnostic assay for virulent Shigella sonnei.
- To enable point-of-care detection of S. sonnei using a multiplex multiple cross displacement amplification (MCDA) assay combined with a lateral flow biosensor (LFB).
Main Methods:
- A multiplex MCDA-LFB assay was designed to detect the ipaH and wbgX virulence genes.
- The assay was optimized for detection limits, specificity, and performance in simulated fecal samples and clinical isolates.
- Incubation was performed at a constant temperature of 63°C for 30 minutes.
Main Results:
- The assay detected wbgX at ≥1 pg/μL and ipaH at ≥10 fg/μL in pure cultures within 30 minutes.
- Sensitivity was demonstrated for approximately 37 CFU of virulent S. sonnei and 3.7 CFU of Shigella spp. and enteroinvasive E. coli in fecal samples.
- The assay showed 100% specificity among 59 reference strains and accurately differentiated S. sonnei from other Shigella and E. coli strains in 99 clinical isolates.
Conclusions:
- A multiplex MCDA-LFB assay provides a rapid, convenient, and accurate method for identifying virulent S. sonnei.
- This assay is suitable for point-of-care use, requiring only 30 minutes and constant temperature without specialized equipment.
- The developed assay aids in timely diagnosis and management of S. sonnei infections.
