Protective effect of DNA vaccine with the gene encoding 55kDa antigen fragment against Pneumocystis carinii in mice

Abstract

Objective To evaluate the protective effect of DNA vaccine with the gene encoding 55kDa antigen fragment of Pneumocystis carinii ( P. carinii) against P. carinii in mice. Methods The fragment of the antigen within p55(p55-582) was cloned. Then recombinant plasmid was constructed based on the eukaryotic expression vector pcDNA3.1(+). BALB/c mice were used as experimental models to examine the immunogenicity of pcDNA3.1(+)−p55-582. ELISA and RT-PCR were used to evaluate the role of this kind of DNA vaccine. Results The results of western blot indicated that the recombinant DNA[pcDNA3.1(+)−p55-582] could be expressed correctly and had antigenicity in transfected COS-7 cells. ELISA and RT-PCR showed that pcDNA3.1(+)−p55-582 elicited antibody production, stimulated lymphocyte proliferation and provided partial protection by reducing the P. carinii burden. Conclusions The data demonstrate that pcDNA3.1(+)−p55-582 might be potent vaccination that can afford the partial protection for the immunized animals.