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

• Published in: PLoS neglected tropical diseases Vol. 14; no. 1; p. e0008039
• Main Authors: Mora-Cárdenas, Erick, Aloise, Chiara, Faoro, Valentina, Knap Gašper, Nataša, Korva, Miša, Caracciolo, Ilaria, D’Agaro, Pierlanfranco, Avšič-Županc, Tatjana, Marcello, Alessandro
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.01.2020; Public Library of Science (PLoS)
• Subjects: Animals; Antibodies; Antibodies, Viral - blood; Antigens; Biology and Life Sciences; Biotechnology; Cloning, Molecular; Cross-reactivity; Defence mechanisms; Dengue; Dengue fever; Detection; Disease control; Encephalitis; Enzyme-Linked Immunosorbent Assay - methods; Enzymes; Female; Flavivirus Infections - blood; Flavivirus Infections - diagnosis; Gene Expression Regulation, Viral; Genetic engineering; Health sciences; HEK293 Cells; Human diseases; Humans; Immune response; Immune system; Immunity; Immunization; Immunoglobulin G - blood; Immunoglobulin M - blood; Immunology; Infections; Laboratories; Medicine and Health Sciences; Mice; Mice, Inbred BALB C; NS1 protein; Pathogens; Peptides; Plasmids; Protein purification; Proteins; Recombinant Proteins; Recombinants; Research and Analysis Methods; Sensitivity analysis; Sensitivity and Specificity; Serologic Tests - methods; Serology; Specificity; Symptoms; Tick-borne encephalitis; Tropical diseases; Vaccines; Vector-borne diseases; Viral Nonstructural Proteins - immunology; Virology; Viruses; Water purification; West Nile virus; Zoonoses; Italy; Europe; Slovenia
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0008039

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.