AUTHOR=Cao Qilong , Liang Shaoshuai , Wang Lin , Cao Jun , Liu Mengyang , Li Shengpeng , Cao Xiaolong , Guo Yan 

TITLE=A Rapid Detection of Haemophilus influenzae Using Multiple Cross Displacement Amplification Linked With Nanoparticle-Based Lateral Flow Biosensor

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2021.721547

DOI=10.3389/fcimb.2021.721547

ISSN=2235-2988

ABSTRACT=<p><italic>Haemophilus influenzae</italic> is a major human pathogenic bacterium, resulting in a series of diseases, such as pneumonia, bacteremia, meningitis. However, it is hard to diagnose <italic>H</italic>. <italic>influenzae</italic> quickly. In this study, the multiple cross displacement amplification (MCDA) and nanoparticle-based lateral flow biosensor (LFB) (MCDA-LFB) were combined to detect <italic>H</italic>. <italic>influenzae</italic>, which has been proven to be reliable, rapid, and not complicated. On the basis of <italic>H</italic>. <italic>influenzae</italic> outer membrane protein <italic>P6</italic> gene, 10 specific primers were designed. The best MCDA condition was 61°C for 1 h. The sensitivity of <italic>H</italic>. <italic>influenzae</italic>-MCD-LFB assay showed, in the pure cultures, the minimum concentration of genomic DNA templates was 100 fg. The specificity of <italic>H</italic>. <italic>influenzae</italic>-MCD-LFB assay showed only <italic>H</italic>. <italic>influenzae</italic> templates were detected, and no cross-reactivity was found in non-<italic>H</italic>. <italic>influenzae</italic> isolates and other <italic>Haemophilus</italic> species. In 56 sputum samples, with MCDA-LFB method and PCR detection, 21 samples were positive, which was in consistent with the traditional culture method. The accuracy of diagnosis of MCDA-LFB, in comparison with the traditional culture method and PCR detection, can reach 100%, indicating that the MCDA-LFB assay gains an advantage over the cultured-based method for target pathogen detection. In conclusion, the MCDA-LFB assay is suitable for the sensitive, rapid, and specific detection of <italic>H</italic>. <italic>influenzae</italic>, which might be used as a potential diagnostic tool for <italic>H</italic>. <italic>influenzae</italic> in basic and clinical laboratories.</p>