Comparison of Microneutralization and Histo-Blood Group Antigen-Blocking Assays for Functional Norovirus Antibody Detection

Abstract

Background: The development of an in vitro cultivation system for human noroviruses allows the measurement of neutralizing antibody levels.

Methods: Serum neutralizing antibody levels were determined using a GII.4/Sydney/2012-like virus in human intestinal enteroids in samples collected before and 4 weeks after administration of an investigational norovirus vaccine and were compared with those measured in histo-blood group antigen (HBGA)-blocking assays.

Results: Neutralizing antibody seroresponses were observed in 71% of 24 vaccinated adults, and antibody levels were highly correlated (r = 0.82, P < .001) with those measured by HBGA blocking.

Conclusions: HBGA-blocking antibodies are a surrogate for neutralization in human noroviruses.

Clinical trials registration: NCT02475278.

Keywords: human norovirus; antibody; histo-blood group antigen; human intestinal enteroids; immunogenicity; neutralization; vaccine.

© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Figures

Figure 1.

Correlation of Sydney/2012-like virus neutralizing antibody titers determined by interpolation with histo-blood group antigen–blocking antibody titers measured against consensus GII.4 (GII.4c) (A) and Sydney/2012 (B) strains. Dots represent test results for the serum samples (n = 48) from the vaccine study, and some values are overlapping. Abbreviations: BT50, blocking titer 50%; HBGA, histo-blood group antigen.