Comparative specificity and sensitivity of NS1-based serological assays for the detection of flavivirus immune response

PLoS Negl Trop Dis. 2020 Jan 29;14(1):e0008039. doi: 10.1371/journal.pntd.0008039. eCollection 2020 Jan.

Abstract

Flaviviruses are relevant animal and human pathogens of increasing importance worldwide. The similarities of the initial clinical symptoms and the serological cross-reactivity of viral structural antigens make a laboratory diagnosis of flavivirus infection problematic. The main aim of the present study was the comparative specificity and sensitivity analysis of the non-structural protein NS1 as an antigen to detect flavivirus antibodies in sera from exposed individuals. A strategy for the purification of native recombinant non-structural protein 1 of representative flaviviruses including tick-borne encephalitis, West Nile, Zika and dengue virus was developed. The immunological properties of the purified antigens were analyzed using sera of immunized mice and of infected individuals in comparison with standard commercial assays. Recombinant NS1 protein was confirmed as a valuable option for the detection of flavivirus antibodies with reduced cross-reactivity and high sensitivity offering additional advantages for the detection of vaccine breakthrough cases.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Cloning, Molecular
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Female
  • Flavivirus Infections / blood*
  • Flavivirus Infections / diagnosis*
  • Gene Expression Regulation, Viral
  • HEK293 Cells
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Mice
  • Mice, Inbred BALB C
  • Recombinant Proteins
  • Sensitivity and Specificity
  • Serologic Tests / methods*
  • Viral Nonstructural Proteins / immunology*

Substances

  • Antibodies, Viral
  • Immunoglobulin G
  • Immunoglobulin M
  • NS1 protein, Flavivirus
  • Recombinant Proteins
  • Viral Nonstructural Proteins

Grants and funding

Region Friuli Venezia Giulia (FVG) Project SEVARE and Beneficientia Stiftung Project BEN 2016/13 to AM; Slovenian Research Agency Project P3-0083 to TAZ. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.