Rapid quantification of sputum eosinophil peroxidase on a lateral flow test strip

Wolfe, Michael G; Mukherjee, Manali; Radford, Katherine; Brennan, John D.; Nair, Parameswaran

doi:10.1111/all.13711

Cited by 9 publications

(8 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4D), indicating that www.nature.com/scientificreports/ the assay is compatible with complex sputum samples. These LOD values are also comparable to a published antibody-based EPX assay (circa 6 nM EPX) 12 .…”

Section: Resultssupporting

confidence: 83%

“…This was encouraging as EPX and MPO share 70% amino acid sequence identity and 81% sequence similarity according to a protein BLAST search (EPX UniProt #P11678, MPO #P05164) 24 . Next, the analytical sensitivity of the assay was determined using pure EPX with concentrations spanning the clinically relevant range of 1 nM–1 µM (77 ng/mL–77 µg/mL) 10 , 12 , 25 . This resulted in a limit of detection (LoD) of 1 nM (blank + 3σ) when using a plate reader, although the naked-eye limit of detection was approximately 25 nM (based on the images of the microwell plates shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

“…* email: parames@mcmaster.ca; brennanj@mcmaster.ca developed for this target, recent research has shown that the possibility of an autoimmune response to eosinophil degranulation products such as EPX can result in a high polyclonal IgG presence in the airways 11 . This high IgG presence can complicate rapid antibody lateral flow detection systems, requiring additional sample processing steps 12 . As an alternative, DNA aptamers have garnered substantial interest as biorecognition elements.…”

mentioning

confidence: 99%

See 2 more Smart Citations

A sputum bioassay for airway eosinophilia using an eosinophil peroxidase aptamer

Ali

Wolfe

Mukherjee

et al. 2022

Sci Rep

View full text Add to dashboard Cite

Eosinophils are granulocytes that play a significant role in the pathogenesis of asthma and other airway diseases. Directing patient treatment based on the level of eosinophilia has been shown to be extremely effective in reducing exacerbations and therefore has tremendous potential as a routine clinical test. Herein, we describe the in vitro selection and optimization of DNA aptamers that bind to eosinophil peroxidase (EPX), a protein biomarker unique to eosinophils. Fifteen rounds of magnetic bead aptamer selection were performed prior to high throughput DNA sequencing. The top 10 aptamer candidates were assessed for EPX binding using a mobility shift assay. This process identified a lead aptamer candidate termed EAP1-05 with low nanomolar affinity and high specificity for EPX over other common sputum proteins. This aptamer sequence was further optimized through truncation and used to develop an easy-to-use colourimetric pull-down assay that can detect EPX over a concentration range from 1 – 100 nM in processed sputum. Forty-six clinical samples were processed using a new sputum dispersal method, appropriate for a rapid assessment assay, that avoids centrifugation and lengthy processing times. The assay showed 89% sensitivity and 96% specificity to detect eosinophilia (compared to gold standard sputum cytometry), with results being produced in under an hour. This assay could allow for an easy assessment of eosinophil activity in the airway to guide anti-inflammatory therapy for several airway diseases.

show abstract

Section: Resultssupporting

confidence: 83%

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

A sputum bioassay for airway eosinophilia using an eosinophil peroxidase aptamer

Ali

Wolfe

Mukherjee

et al. 2022

Sci Rep

View full text Add to dashboard Cite

show abstract

“…However, performance of sputum eosinophil counts is both laborious and fraught with considerable lab-to-lab and patient-to-patient variability. Fortunately, efforts to develop rapid immunoassays, such as measurement of EPX or CLC/Galectin-10 in induced sputum extracts (135,136), are showing considerable clinical promise and utility for identifying patients with eosinophilic asthma for targeted therapy with anti-eosinophilic agents.…”

Section: Less/minimally Invasive Biomarkers Of Disease Activity and Remissionmentioning

confidence: 99%

Contributions of Eosinophils to Human Health and Disease

Klion

Ackerman

Bochner

2020

Annu. Rev. Pathol. Mech. Dis.

180

178

View full text Add to dashboard Cite

The human eosinophil has long been thought to favorably influence innate mucosal immunity but at times has also been incriminated in disease pathophysiology. Research into eosinophil biology has uncovered a number of interesting contributions by eosinophils to health and disease. However, it appears that not all eosinophils from all species are created equal. It remains unclear, for example, exactly how having eosinophils benefits the human host when helminth infections in the developed world have become scarce. This review focuses on our current state of knowledge as it relates to human eosinophils. When information is lacking, we discuss lessons learned from mouse studies that may or may not directly apply to human biology and disease. It is an exciting time to be an “eosinophilosopher” because the use of biologic agents that selectively target eosinophils provides an unprecedented opportunity to define the contribution of this cell to eosinophil-associated human diseases.

show abstract

“…In children, the presence of blood eosinophilia, especially in combination with allergic sensitization, was found to be a significant predictor of ICS response with respect to both asthma symptoms and exacerbations . Recently, a novel point‐of‐care method for rapid quantification of eosinophil peroxidase in sputum has been described which can identify patients with airway eosinophilia …”

Section: Biomarkers Of T2 Inflammationmentioning

confidence: 99%