Highlights • An ELISA based cPass assay provides a measure of Spike RBD binding antibodies. • Binding in a cPass ELISA correlates strongly with pseudotyped virus neutralisation. • ELISA-based surrogate assays provide rapid data on neutralising capacity. Objectives To assess whether a commercially available CE-IVD, ELISA-based surrogate neutralisation assay (cPass, Genscript) provides a genuine measure of SARS-CoV-2 neutralisation by human sera, and further to establish whether measuring responses against the RBD of S was a diagnostically useful proxy for responses against the whole S protein. Methods Serum samples from 30 patients were assayed for anti-NP responses, for ‘neutralisation’ by the surrogate neutralisation assay and for neutralisation by SARS-CoV-2 S pseudotyped virus assays utilising two target cell lines. Correlation between assays was measured using linear regression. Results The responses observed within the surrogate neutralisation assay demonstrated an extremely strong, highly significant positive correlation with those observed in both pseudotyped virus assays. Conclusions The tested ELISA-based surrogate assay provides an immunologically useful measure of functional immune responses in a much quicker and highly automatable fashion. It also reinforces that detection of anti-RBD neutralising antibodies alone is a powerful measure of the capacity to neutralise viral infection.
【초록키워드】 SARS-CoV-2, viral infection, S protein, spike, ELISA, Viral, Pseudotyped virus, neutralising antibody, immune responses, response, Patient, Linear regression, neutralisation assay, neutralisation, cell lines, anti-RBD, target cell, serum samples, positive correlation, measure, Highlights, human sera, SARS-CoV-2 S, serum sample, functional immune response, responses, objective, neutralising, Result, was measured, tested, assays, provide, demonstrated, the RBD, responses against, immunologically, neutralise, RBD binding antibodies, 【제목키워드】 validation, Pseudotyped virus, SARS-CoV-2 neutralising antibody,