Abstract
Background: Neutralizing antibodies (NAbs) against SARS-CoV-2 have been shown to correlate with protection against infection. Simple tools such as lateral flow assays (LFA) that can accurately measure NAbs may be useful for monitoring anti-SARS-CoV-2 immunity in the future.
Objectives: We assessed the performance of the ichroma™ COVID-19 nAb test, a rapid semiquantitative LFA, for the prediction of serum neutralizing activity against SARS-CoV-2 variants.
Study design: Serum samples were collected from COVID-19 recovered patients and vaccinated individuals. The result of the ichroma assay was provided as inhibition rate, and was compared to anti-SARS-CoV-2 IgG levels, and NAbs against Alpha, Delta and Omicron variants.
Results: A total of 90 sera from recovered unvaccinated patients and 209 sera from the vaccine cohort were included in this study. In post-infection samples, the ichroma inhbition rate was found to be correlated with IgG levels (ρ = 0.83), and with anti-Alpha NAbs levels (ρ = 0.78). In the vaccine cohort, a good correlation was also observed between the ichroma inhibition rate and IgG levels (ρ = 0.84), as well as NAbs against Alpha (ρ = 0.62), Delta (ρ = 0.88) and Omicron (ρ = 0.74). An ichroma inhbition rate of 77.2%, 90.8% and 99.6% accurately predicted neutralization against Alpha, Delta and Omicron variants respectively.
Conclusions: The ichroma™ COVID-19 nAb assay, with appropriate variant cut-offs, can be useful for the monitoring of anti-SARS-CoV-2 immunization and may provide a rapid prediction of protection, especially in individuals with significant levels of NAbs.
Keywords: Lateral flow assay; Neutralizing antibodies; SARS-CoV-2; Variants.
【저자키워드】 SARS-CoV-2, Neutralizing antibodies, lateral flow assay, variants., 【초록키워드】 COVID-19, Immunity, antibody, neutralization, variant, Infection, Delta, omicron, anti-SARS-CoV-2, immunization, variants, lateral flow, serum, Neutralizing activity, Cohort, SARS-CoV-2 variants, anti-SARS-CoV-2 IgG, sera, Patient, correlation, NAb, Post-infection, individual, NAbs, vaccinated individuals, cut-offs, significant level, serum sample, simple, COVID-19 recovered patient, shown, predicted, collected, provided, correlated, the vaccine, IgG level, Lateral, 【제목키워드】 SARS-CoV-2 variant, lateral flow, serum, Neutralizing activity,