Generation of recombinant Schmallenberg virus nucleocapsid protein in yeast and development of virus-specific monoclonal antibodies

J Immunol Res. 2014;2014:160316. doi: 10.1155/2014/160316. Epub 2014 May 29.

Abstract

Schmallenberg virus (SBV), discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N) protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs). Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / biosynthesis
  • Antibodies, Viral / biosynthesis
  • Bunyaviridae Infections / diagnosis
  • Bunyaviridae Infections / epidemiology
  • Bunyaviridae Infections / immunology
  • Bunyaviridae Infections / veterinary*
  • Cattle
  • Cattle Diseases / diagnosis*
  • Cattle Diseases / epidemiology
  • Cattle Diseases / immunology
  • Cattle Diseases / virology
  • Cell Line
  • Cricetinae
  • Female
  • Gene Expression
  • Immune Sera
  • Immunization
  • Immunoglobulin G / biosynthesis
  • Lithuania / epidemiology
  • Mice
  • Mice, Inbred BALB C
  • Nucleocapsid Proteins / administration & dosage
  • Nucleocapsid Proteins / biosynthesis*
  • Nucleocapsid Proteins / genetics
  • Nucleocapsid Proteins / immunology
  • Orthobunyavirus / immunology
  • Orthobunyavirus / isolation & purification*
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / biosynthesis*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism

Substances

  • Antibodies, Monoclonal
  • Antibodies, Viral
  • Immune Sera
  • Immunoglobulin G
  • Nucleocapsid Proteins
  • Recombinant Proteins