中国生物工程杂志

Objective: To study preparation and immunogenicity of a scalable inactivated human rotavirus vaccine, strain ZTR-5 in mice. Method: The clones of rotavirus ZTR-5 strain cultured in MA104 cells were purified by plaque screening and inoculated to Vero cell for adaptive cultivation, then determined for infectious titer by FFA, the harvest virus solution was purified by Centrifugation, ultrafiltration and molecular sieve, then inactivated by formaldehyde, quantitatively detected for content of antigen with Al(OH)₃ adsorption which was experimental vaccine. Using different doses (8EU, 32EU, 128EU, 256EU) immunized mice by intramuscular injection, a total of three immune and immune interval of 2 weeks. Detected for the serum antibody titers by indirect ELISA. Results: By plaque purification, screened a purified strain that was the virus ZTR-5 pure-1,and infectious titer reached 7.35logCCID₅₀/ml after adaptive cultivation in Vero cells. The infectious titer of virus original solution acquired after large-scale cultivation was 7.57logCCID₅₀/ml, and the antigenic content of the manufactured and obtained rotavirus samples was 2 560EU/ml. All animals of dose group had received positive seroconversion after the initial immunization by intramuscular injection and seroconversion rate was 100%. After the first booster immunization, the serum antibody levels were significantly higher, and the mice serum antibody titers of the two dose groups (256EU and 128EU) reached 1∶10 240. After the second booster immunization, each dose group (8EU, 32EU, 128EU, 256EU) serum antibody titers followed up 1∶5 120, 1∶7 456, 1∶14 481.54, 1∶14 481.54. Conclusion: Human rotavirus ZTR-5 strain was stably proliferated in Vero cell, and the prepared vaccine had good immunogenicity and got a good immune effects with 128EU/2 times.