RESUMEN
<p><b>OBJECTIVE</b>To develop a coexpression plasmid which expressing envelope protein and nucleoprotein of hepatitis B virus and know of its expressing efficiency.</p><p><b>METHODS</b>The plasmid coexpressing envelope protein and nucleoprotein of hepatitis B virus under the CMV promoter respectively was constructed by gene recombination. Cellular expression was assessed by ELISA.</p><p><b>RESULTS</b>Multiple cloning site was inserted into expression vector contain hepatitis B virus PreS2-S gene. And expression unit containing hepatitis B virus PreC-C was cloned into it. HBsAg and HBeAg was detected both in the culture supernatant and in the cells.</p><p><b>CONCLUSION</b>The coexpressing plasmid was constructed successfully and it can express effectively in vitro. This has provided a basis for further research of the therapeutic HBV DNA vaccine.</p>