%0 Journal Article %A Dayna Mikkelsen %A Jennifer A. Aguiar %A Julia Danieli %A Prakriti Chhabra %A Benjamin J-M Tremblay %A Manjot S. Hunjan %A Victoria Kirkness %A Jodi Gilchrist %A David Bulir %A Marek Smieja %A Sojin Lee %A Nader Shaikh %A Hamza Mbareche %A Samira Mubareka %A Kha Tram %A Andrew C. Doxey %A Jeremy Hirota %T Validation of CXCL10 as a biomarker of respiratory tract infections detectable by lateral flow immunoassay %D 2022 %R 10.1183/23120541.LSC-2022.66 %J ERJ Open Research %P 66 %V 8 %N suppl 8 %X Introduction: Biomarkers of respiratory tract infections historically focused on the etiological cause of infection, although much of the morbidity and mortality is driven by the host-pathological response.Aim: Determine host biomarkers indicative of viral respiratory tract infections that are amenable to lateral flow immunoassay (LFIA) testing.Methods: Datamining was performed on in-house and publicly available datasets from respiratory syncytial virus (RSV), rhinovirus, influenza A and SARS-CoV-2 infected patient nasopharyngeal swab samples and compared to healthy controls. CXCL10, CXCL11 and TNFSF10 gene expression levels were assessed and a correlation analysis was performed in relation to infection severity and time-course. Lastly, the signature was validated at the protein level in saliva as a prerequisite for development of a host-response LFIA.Results: CXCL10 and CXCL11 upregulation was positively correlated with RSV when compared to control (p= 0.016, p= 0.006). No significant association was found with influenza A or rhinovirus for all three genes. CXCL10/CXCL11/TNFSF10 upregulation was positively correlated with SARS-CoV-2 infection when compared to control (p < 0.001). CXCL10 expression correlated with COVID-19 severity and had the lowest variance over infection time-course. CXCL10 was not detected at the protein level in healthy saliva but was elevated in saliva from COVID-19 patients. A CXCL10 LFIA was developed with a sensitivity of 2 ng/ml in a buffer and artificial saliva.Conclusion: The findings validate the potential utility of examining host immune responses during viral respiratory tract infections by exploring CXCL10 as a biomarker detectable by LFIA.FootnotesCite this article as ERJ Open Research 2022; 8: Suppl. 8, 66.This article was presented at the 2022 ERS Lung Science Conference, in session “Poster Session 2”.This is an ERS Lung Science Conference abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). %U