Cocultivation of caprine arthritis encephalitis virus-infected macrophages with primary goat synovial cells

摘要

Primary goat synovial cells were developed to be cocultivated with caprine arthritis encephalitis virus (CAEV)-infected monocytes. Two CAEV-seropositive goats and one CAEV-seronegative goat were confirmed for viral particles in the blood using the PCR method. Thereafter, heparinized blood samples from the three goats were collected and isolated for monocytes, which were further cultivated to differentiate into macrophages. Cultivated macrophages of 7-10 days old were cocultivated with the primary goat synovial cells for 7 days. Microscopic examination was performed every 2 days for multinucleated syncytial formation, and immunofluorescence assay was applied using monoclonal antibody against CAEV on day 7 to detect viral particles. Results showed that the primary goat synovial cells cultivated with CAEV-infected macrophages from the two seropositive goats had multinucleated syncytial formation with positive immunofluorescence, while the cocultured macrophages from the seronegative goats showed normal appearance with negative immunofluorescence. The multinucleated syncytial cells were prepared for transmission electron microscope examination and the results indicated that CAEV particles were clearly identified. In conclusion, our developed primary goat synovial cells and the cultivating system were proven to be an appropriate isolation assay for CAEV, which was the first report of cultivation and isolation of CAEV in goats in Thailand.