Evaluation of the protections of multivalent DNA vaccine of Streptococcus pneumoniae containing LytA gene / 重庆医科大学学报

Objective:To evaluate the ability of the cooperative protection of the Strep to coccus pneumoniae multivalent DNA vaccine containing lytA gene(N-acetylmuramoyl-L-alanine amidase,LytA)and pspA'gene(N fragment of pneumococcal surface protein A,PspA)against intraperitoneal Streptococcus pneumoniae D39 infection.Methods The genomic DNA of the standard Streptococcus pneumoniae strain D39 was isolated.LytA gene fragment was amplified by polymerase chain reaction(PCR)and cloned into the eukaryotic expression vector pcDNA3.1(+),which was transfected into BHK-21 cells using Lipofectamine TM2000,and then the expression of LytA protein was detected with Western-blot.Furthermore,three formats of recombinant plasmid DNA vaccines(pcDNA3.1-LytA+pcDNA3.1-PspA',pcDNA3.1-PspA',pcDNA3.1-LytA)were used to inject intramuscularly BALB/c mice,with pcDNA3.1(+)plasmid and PBS as controls.The levels of antibodies against PspA'and LytA proteins were checked.Live times of intraperitoneal infection mice by Streptococcus pneumoniae D39 in BALB/c models were analysis.Results:The three DNA vaccines all producted high levels serum special IgG antibodies.The anti-LytA antibodies level elicited by the DNA vaccine pcDNA3.1-LytA + pcDNA3.1-PspA'was higher than the DNA vaccine pcDNA3.1-LytA(P0.05).The result of the effect on intraperitoneal infection by Streptococcus pneumoniae D39 in BALB/c mice models showed the median live times in pcDNA3.1-LytA + pcDNA3.1-PspA'group was longer than pcDNA3.1-LytA group and the control groups(P0.05).Conclusion:The multivalent DNA vaccine of Streptococcus pneumoniae containing LytA gene and pspA gene had no the higher performance protection than the DNA vaccine only containing pspA gene against Streptococcus pneumoniae.It is should be further evaluated that LytA gene is concluded as the one of advantages candidate antigens of the Streptococcus pneumoniae multivalent DNA vaccine.

Current Status and Prospects on Candidate Vaccines against Schistosoma japonicum / 中国寄生虫学与寄生虫病杂志

Great progress has been made on vaccine research for schistosomiasis,including those on immune mec-hanism and Schistosoma genome which have made active effect to vaccine development.This paper reviews the progress on the candidate vaccine antigens including protein vaccine,DNA vaccine and multivalent vaccine against Schistosoma japonicum.