Abstract: Objective To explore the breeding rule of C57BL/6J-HBV transgenic mice and to conduct a comprehensive study on biological characteristics of the transgenic mice from the DNA, RNA, proteins and virological level. Method C57BL/6J-HBV transgenic mice were breeded in two different ways of mating and breeding, PCR was used to detect the positive rate of transgenic in each generation. RT-PCR and real-time PCR were used to semi-qualitatively or quantitatively detect the expression of HBV DNA in transgenic mice and to explore the transcription characteristics of mRNA coded by HBV. ELISA and Western Blotting were used to HBV virus antigen expression and secretion. Results There were significant differences (P＜0.05) of both litter size and weaning between two mating mode. The positive rate of reciprocal cross progeny was higher than the rate of backcross progeny. Four founder HBV positive transgenic mice were crossed with normal C57 BL/6J mice, and real-time PCR was performed to detect the HBV genome of the offspring during every passage. Analysis showed that the positive rate was always around 40-50%, indicating the HBV genome has integrated into the C57BL/6J-Tg mice’s genome, expressed stably and can transmit into the next generation reliably. Viral antigen can be stablely expressed in the transgenic mice liver tissue and secreted into the blood. Conclusion The transgenic mouse model can be of high expression model of HBV viral antigen with long-term stability and be applicted as the animal model for hepatitis B virus-related research.

Key words: Hepatitis B virus, Transgenic mice, Breeding system