[Studies on effect enhancement of the Schistosoma japonicum DNA vaccine pVIV02-IL12-Sj23 by vegetal polysaccharides].
OBJECTIVE
To enhance the immunogenicity of the recombinant pVIVO2-IL12-Sj23 vaccine of Schistosoma japonicum by using mixed vegetal polysaccharides as adjuvant.


METHODS
The plasmid pVIVO2-IL12-Sj23 was constructed. 3 groups of BALB/C mice were injected intramuscularly with normal saline (Group A), pVIVO2-IL12-Sj23 plasmid DNA (B), and pVIVO2-IL12-Sj23 plus mixed vegetal polysaccharides (C) respectively, and challenged with S. japonicum cercariae on the 4th week after immunization. Mice were killed to calculate the worm reduction rate and egg reduction rate in liver tissue on the 6th week after infection. Before and 4 weeks after immunization blood samples were collected.


RESULTS
The worm reduction rate and egg reduction rate were 64.3% and 79.9%, respectively in group C, 45.5% and 58.4%, respectively in group B, showing a remarkable difference hetween them (P < 0.05). ELISA analysis showed a significantly higher level of IgG specific for Sj23 4 weeks after vaccination in groups B and C (P < 0.05). However, there was no significant difference in IgG level between groups C and B (P > 0.05).


CONCLUSIONS
When mixed vegetal polysaccharides are used as adjuvant, the effect of the vaccine pVIVO2-IL12-Sj23 can he considerably enhanced.
Department of Chemistry, Huazhong University of Science and Technology, Wuhan 430030, China. westwind@public.wh.hb.cn
Qing
Q
Feng
Jun-feng
JF
Hu
Han
H
Chen
Jian-lin
JL
Lou
Yan
Y
Gan
Yuan
Y
Hu
You-en
YE
Shi
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth; D028241:Camellia sinensis / Q000737:chemistry; D005260:Female; D015801:Helminth Proteins; D007074:Immunoglobulin G / Q000097:blood; D018664:Interleukin-12 / Q000235:genetics* / Q000276:immunology; D020074:Lentinula / Q000737:chemistry; D008565:Membrane Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D011897:Random Allocation; D012549:Schistosoma japonicum / Q000276:immunology*; D019444:Vaccines, DNA / Q000276:immunology*
D000276:Adjuvants, Immunologic; D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G; D008565:Membrane Proteins; D011134:Polysaccharides; D019444:Vaccines, DNA; C072633:Sj23 antigen, Schistosoma japonicum; D018664:Interleukin-12