|Title:||The development of a point of care test for the quantitative determination of active neutrophil elastase in sputum|
|Author(s):||McCafferty D Raj S Johnston S Lubarsky G McLaughlin J|
|Institution:||ProAxsis Ltd and Northern Ireland Connected Health Innovation Centre (CHIC)|
|Poster:||Click to view poster|
|Abstract:||Sputum neutrophil elastase (NE) is a biomarker of disease severity in respiratory disorders; with point of care measurement being of interest to assist in patient triaging. NEATstik® is a lateral flow test for the qualitative detection of sputum NE; however, the need for a quantitative device has been highlighted. This study aims to improve the quantitative potential of NEATstik® using a CMOS reader.|
NE calibrants and sputum samples (n=19) were prepared in NEATstik dilution buffer. Sputum samples were initially diluted x10, then serially diluted. NE calibrants and samples were transferred (70µl) to a NEATstik device; with a CMOS reader used to measure signal intensity. Sputum sol was analysed on ProAxsis’ NE Activity based Immunoassay.
CMOS readings revealed a matrix effect, with statistical analysis (Kruskal-Wallis; Dunn’s Multiple Comparison Test) indicating that a further x8 dilution is necessary for the quantitative measurement of active NE, in sputum, with NEATstik. Moreover, a significant correlation (spearman r value = 0.86) was observed between NE levels when measured on both platforms.
Improved accuracy in the quantitative determination of sputum NE may assist in the identification of key disease thresholds, enabling pre-emptive medical intervention, thereby improving the standard of care received by patients with respiratory disease.