Research on Diseases of High Consequence to Swine
Arthropod-Borne Animal Diseases Research
2012 Annual Report
1a.Objectives (from AD-416):
To develop knowledge, diagnostic tools, and control practices and technology to address the threat posed to the U.S. Pork Industry by Classical Swine Fever (CSF), African Swine Fever (ASF) and of other diseases of high consequence.
1b.Approach (from AD-416):
Classical Swine Fever (CSF) and African Swine Fever (ASF) are highly infectious diseases of swine. As foreign animal diseases (FADs), an outbreak of CSF, ASF or an unknown threat would significantly affect the U.S. pork industry and export markets. Improved CSF marker live-attenuated vaccines are needed to further reduce the risk posed by this FAD. There are no commercial ASF vaccines, which is a significant gap in the available interventions to stop the spread of ASF. Furthermore, there is a gap in our understanding on the mechanism of ASF pathogenesis. Other needs include improved diagnostic approaches for conducting surveillance. Underlying this research is improved diagnostics and surveillance.
Classical Swine Fever Virus (CSFV)-The purpose of this project is to express CSFV proteins for serology. One consideration is cross-reactivity with Bovine Viral Diarrhea Virus(BVDV) proteins. CSFV Erns full length and fragments were expressed in bacteria. Expression of the full-length E2 protein was not successful. However, fragments of E2 were expressed. ELISA analysis of E2 and Erns proteins against Bovine Viral Diarrhea Virus (BVDV) sera revealed that the E2 protein has the greatest cross-reactivity with BVDV. Therefore Erns is a better target for assay development.
African Swine Fever Virus (ASFV) Update: Work on ASFV has focused on protein expression. Proteins being expressed include p30, p54, and p72. The expression of full-length genes has not been successful. Efforts are focusing on the expression of protein fragments. P54 and p72 have been inserted into the pcDNA3.1+ vector for expression in eukaryotic cells. The goal of the pcDNA expression is to construct a pseudotyped virus. This will be an important tool for understanding the virus-cell interaction.