Study on optimal proliferation condition of Siniperca chuatsi rhabdovirus in CPB cells

The optimal proliferation condition of Siniperca chuatsi rhabdovirus (SCRV) in CPB cells was determined through detecting the viral copy numbers by Real-Time Reverse Transcription PCR (qRT-PCR). Two inoculation methods including synchronous and asynchronous inoculation and different culture conditions such as the amount of inoculated virus, FBS concentration of the culture medium were investigated in this study. The virus was harvested when the CPE reached 80% and then RNA was extracted for qRT-PCR detection. Results showed that all the above factors had obvious influence on the SCRV proliferation in vitro. When compared with the viral yields in unit volume, asynchronous inoculation method was superior to the synchronous inoculation. The highest amount of virus (5.59×10¹⁰ copies/mL) were obtained when cultured in L-15 medium containing 2% fetal bovine serum at 28 °C for 48 h with MOI=10 and inoculation for 1.5 h. While the viral yields with unit cost was compared, 4 proliferation conditions with synchronous inoculation method were singled out which were superior to asynchronous inoculation. The highest viral yields per unit cost (4.88×10¹³ copies/yuan) were obtained when SCRV was inoculated to the CPB cells at the middle-log phase with a MOI=0.03 and cultured with L-15 medium containing 6% fetal bovine serum and harvested after culturing at 28 ° C for 70 h. In conclusion, viral yield and the medium cost were studied as the assessment criteria for SCRV proliferation in CPB cells in this paper, and it provided the theoretical basis for SCRV vaccine production with low cost through the comprehensive viral yield analysis of the medium cost.