Study on the anti-tumor effect of Bluetongue virus-HBC3 on murine renal cell carcinoma cell line Renca in vitro and in vivo

Objective To investigate the anti-tumor effect of Bluetongue virus-HBC3 on murine renal cell carcinoma cell ( Renca) in vitro and in vivo. Methods The renal cells were inoculated with BTVHBC3 at MOI of 1. Observed the cytopathic effects (CPE) by microscopy and the ultra-structural changes by transmission electron. MTT assay was used to comparative analyses of differential survival rates using different Multiplicities of Infection ( MOI) after the renal cells were infected 24,36,48 h. The presence of BTV genome was also detected by agarose gel electrophoresis. The subcutaneous tumor-bearing mice model of renca cells were created up successfully using the BALB/c mice,and the mice was intratumorally injected with BTV-HBC3. Observed the tumor growth, and the pathological and immunohistochemical of the tumor tissue. We also detected the serum IFN-α of the mice. Results Over 90% cytopathic effects (CPE) were readily observed and detected in renca cells infected with BTV 48h postinfection. In electron microscopy (EM), BTV virions could be seen amplified efficiently in renca cells. The survival rate of the renca cell were respectively (44.45 ± 5. 26) % , (30. 47 ± 4. 77)% , ( 20. 34 ± 5. 26 ) % when infected with BTV at MOI of 1 24,36,48 h postinfection. It showed that there was a dose-effect relationship between them. BTV viral genomic ds-RNA fragments could be found in BTV infected Renca cells through gel electrophoresis. The tumor volume reduced dramatically in contrast with the control group. After BTV treatment Subsequent pathological and immunohistochemical analysis also demonstrated its distinct infection restricted in the Rencacells. Conclusion BTV-HBC3 could selectively degradated Renca cells. Key words: Oncolytic virus; Bluetongue virus; Renal cell carcinoma