visual and rapid detection of klebsiella pneumoniae by magnetic immunocapture-loop-mediated isothermal amplification assay

Background: klebsiella pneumoniae is an important human pathogen that causes severe diseases including urinary tract infection, pneumonia, and bacteremia. however, a rapid and sensitive detection method remains to be developed. objectives:this study aimed to develop a rapid, realtime, and visual detection method for k. pneumoniae. this is a primary screening method to improve the diagnosis of k. pneumoniae infection and save much precious time for clinical practice. methods: klebsiella pneumoniae was used as an antigen to produce a monoclonal antibodies (mab). the mab 1e6 recognizing outer membrane protein c on the surface of k. pneumoniae was screened by an indirect enzymelinked immunosorbent assay (elisa), western blot, and mass spectrometry assay, and then conjugated with the protein a/g coated magnetic beads to generate the immune magnetic beads (imbs). thereafter, the imbs were used to capture k. pneumoniae, and the complex (beadsmab k. pneumoniae) was used for loopmediated isothermal amplification (lamp) assay. results:we developed a rapid, realtime, and visual detection method employing an immunocapture loopmediated isothermal amplification (iclamp). the sensitivity of the iclamp was 4 cfu ml<sup&>1</sup&>. the process of k. pneumoniae detection lasted ~ 60 minutes and had no crossreaction to other microbial strains. besides, the accuracy of iclamp was further verified by examining 39 clinical isolates. conclusions:without the need for enrichment of bacteria and extraction of its genome, the iclamp developed here could be used as a primary screening method supplementary to traditional detection methods to improve the diagnosis of k. pneumoniae infection for clinical practice.