Serotyping and Adaptation of Foot and Mouth Disease Virus in BHK-21 Cell Line towards the Development of Vaccine Candidate

Abstract

This research work was conducted for isolation, identification and serotyping of Foot and Mouth Disease (FMD) virus from the field isolates of Gouripur Upazila of Mymensingh district, Bangladesh. Samples were collected from infected cattle in virus transportation medium and transported at the Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh with maintain proper cool chain duringOctober to April 2012. Inocula were prepared from the collected samples and treated with antibiotics-antimycotics, preserved at -20°C for isolation and serotyping of the virus by antigen detecting ELISA method. After serotyping, the prepared inoculum was inoculated into 24hours confluent BHK-21 cell culture separately and incubated at 37°C for 48hours for development of CPE. Within 48hours of post infection, complete development of cytopathic effects (CPE) in BHK-21 cell culture were observed under inverted microscope which included the rounding and flattening of the cells, breaking down of the intracellular bridges and finally cell death which indicated the presence of FMD virus. Clear BHK-21 cell culture fluid was collected and preserved at -80°C as seed. Of the 20 samples, 15(75%) samples were found positive for FMDV in cell culture of which 13 samples of tongue epithelia (86.67%) and 2 samples of foot tissues (40%) were positive on the basis of cytopathic effects (CPE). Again the prepared inoculum was taken for serotyping the virus by ELISA method. On the basis of the result of ELISA, it was concluded that the serotype of the FMD virus of the collected field isolate was serotype “O”.