[The construction of recombinant plasmids of Toxoplasma gondii P30 and the immunoprotective activity of the P30 constructs].
OBJECTIVE
To identify the potential DNA vaccine candidate which can induce the protective immune response to Toxoplasma gondii by inoculating mice with plasmid DNAs encoding three different forms of P30 antigen (membranous secretory, and intracellular).


METHODS
Three forms of recombinant plasmid: pcDNA3-P30Mb(contain the whole P30 gene sequence, including the gene encoding signal peptide and hydrophobic tail), pcDNA3-P30Se(contain the whole P30 gene sequence, without the gene encoding hydrophobic tail) and pcDNA3-P30In(contain the whole P30 gene sequence, without the gene encoding signal peptide) were constructed by PCR and subcloning technique. The mice were immunized with different forms of recombinant plasmids and IgG antibodies in the mice were detected by ELISA and Western blotting.


RESULTS
Three forms of expression recombinant plasmid of Toxoplasma gondii P30 gene were successfully constructed. The P30 inserts were identified by restrictive enzyme digestion and sequencing. ELISA and Western blotting analysis demonstrated that specific IgG antibody could be induced in three immunized groups, but there was some difference in appearence time and intensity of IgG.


CONCLUSIONS
Genetically immunization of mice with the recombinant plasmids could elicit specific IgG antibodies. In respect to IgG response, the immune efficiency of the three forms of recombinant plasmids was different at the beginning (2 wk), but 4 wk later approximately same.
Gong
Y
Y
Department of Parasitology, First Military Medical University, Guangzhou 510515.
Chen
X G
XG
Feng
M Z
MZ
D000818:Animals; D016054:DNA, Protozoan / Q000276:immunology*; D004274:DNA, Recombinant / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*; D019444:Vaccines, DNA / Q000276:immunology*
D016054:DNA, Protozoan; D004274:DNA, Recombinant; D007074:Immunoglobulin G; D019444:Vaccines, DNA