Related Experiment Videos
Serological probes for some foot-and-mouth disease virus nonstructural proteins
M Tesar1, H G Berger, O Marquardt
1Federal Research Center for Virus Diseases of Animals, Tübingen, Federal Republic of Germany.
Abstract:
Foot-and-mouth disease virus (FMDV) O1 Kaufbeuren-specific cDNA fragments were subcloned into the E. coli expression vector pRIT.2T. Fusion proteins thus produced in bacteria were purified by affinity chromatography and inoculated into rabbits. Three sera thus obtained were found to be monospecific for FMDV proteins 3A, 3C, and 3D, respectively. Two others were prevalently directed against protein 2C, but in addition, either to protein 2B or to protein 3A. Five out of six mature nonstructural virus proteins can therefore be separately investigated in FMDV-infected cells, either by indirect immunofluorescence or by radioimmunoprecipitation. Immunofluorescence shows all investigated proteins to be located exclusively in the cytoplasm. One of them, protein 2C, transiently forms aggregates at the periphery of cells. Radioimmunoprecipitation confirmed current knowledge on maturation of FMDV proteins. It was further used to characterize postinfectional sera with regard to FMDV-specific antibodies. Cattle and guinea pig were found to have responded differently to FMDV nonstructural antigens. Furthermore, antigenicity of yet to be described FMDV polypeptides was observed in the guinea pig.
Insights
Researchers developed specific antibodies to study Foot-and-mouth disease virus (FMDV) nonstructural proteins. These tools enable detailed investigation of viral protein functions and locations within infected cells.
Area of Science:
- Virology
- Immunology
- Molecular Biology
Background:
- Foot-and-mouth disease virus (FMDV) is a significant pathogen affecting livestock.
- Understanding the roles of FMDV nonstructural proteins is crucial for developing effective control strategies.
- Existing methods for studying these proteins have limitations.
Purpose of the Study:
- To generate specific antibodies against FMDV nonstructural proteins.
- To characterize the cellular localization and behavior of these proteins.
- To evaluate host immune responses to FMDV nonstructural antigens.
Main Methods:
- Subcloning of FMDV O1 Kaufbeuren cDNA fragments into an E. coli expression vector.
- Purification of bacterial fusion proteins via affinity chromatography.
- Production of rabbit antisera against purified proteins.
- Application of indirect immunofluorescence and radioimmunoprecipitation assays.
- Analysis of postinfectional sera from cattle and guinea pigs.
Main Results:
- Monospecific antibodies were obtained for FMDV proteins 3A, 3C, and 3D.
- Additional antibodies targeted protein 2C, with some cross-reactivity to 2B or 3A.
- Five of six mature nonstructural FMDV proteins were amenable to separate investigation.
- Immunofluorescence revealed exclusive cytoplasmic localization for all studied proteins.
- Protein 2C was observed to transiently form aggregates at the cell periphery.
- Radioimmunoprecipitation confirmed FMDV protein maturation and identified differential immune responses in cattle and guinea pigs.
- Novel antigenicity of FMDV polypeptides was detected in guinea pigs.
Conclusions:
- The developed antibodies provide valuable tools for studying FMDV nonstructural proteins.
- These proteins are primarily located in the cytoplasm, with dynamic behavior observed for protein 2C.
- Host immune responses to FMDV nonstructural antigens vary between species.
- Further investigation into FMDV polypeptide antigenicity in guinea pigs is warranted.