OBJECTIVETo provide experimental evidence for development of human cytomegalovirus (HCMV) nucleic acid vaccine, HCMV surface protein (gB), membrane protein (pp150), and gB-pp150 fused gene eukaryotic expression vector were constructed.

METHODSgB and pp150 genes were amplified and fused into gB-pp150, then were cloned into pcDNA 3.1 (+) to obtain recombinant expression plasmids pcDNA 3.1 (+) -gB, pcDNA 3.1 (+) -pp150 and pcDNA 3.1 (+) -gB-pp150, which were encapsulated with chitosan. Mouse were vaccinated and the humoral and cell immune response were determined by ELISA, specific proliferative response of plenic lymphocytes.

RESULTSThe gB, pp150 and gB-pp150 fusion gene eukaryotic expression vector were successfully constructed. The antibodies A value induced by pcDNA3.1(+) -gB or pcDNA3.1 (+) -gB-pp150 were much higher than that of pcDNA3.1 (+) (P < 0.01). The IFN-gamma levels induced by pcDNA3.1 (+) -pp150 and pcDNA3.1 (+) -gB-pp150 were significantly higher than that of pcDNA3.1 (+). There are significant diference between the stimulating indexes of pcDNA3.1(+) -pp150 or pcDNA3.1 (+) -gB-pp150 immunized and normal mice.

CONCLUSIONThe DNA vaccine pcDNA3.1 (+) -gB can induce significant humoral immunity response, and pcDNA3.1 (+) -pp150 can induce high cellular immune response, whereas pcDNA3.1 (+) -gB-pp150 can induce both humoral and cellar immune responses in BALB/c mice.