[Comparison of immune responses elicited by recombinant protein and eukaryotic expression plasmid based on histidine rich protein 2 of Plasmodium falciparum].
OBJECTIVE
To identify the immune characteristics of different vaccine prototypes based on HRP2 and to provide experimental evidence for developing P. f. blood stage vaccines.


METHODS
BALB/c mice were immunized with recombinant protein TP-HRP2 or eukaryotic expression plasmid pcDNA3.1(-)/HRP2. The kinetics and specificities of antibody responses were analyzed. The proliferation tests of spleen cells were done, and P. f. growth inhibition assays were done with immune sera.


RESULTS
The mice immunized with TP-HRP2 in Freund's adjuvant produced high-level and high-specificity antibody response. The antibodies appeared rapidly and lasted for a longer time. Cellular responses were induced simultaneously, and the immune sera could inhibit the development of parasite in IRBCs. The mice immunized with pcDNA3.1(-)/HRP2 produced middle-level antibody response which had some specificity, however, the induction of antibodies required repeated inoculation and a longer duration. Immune cells were well primed and the memorial immune response was obvious but the immune sera had no effect on the growth of P.f. in vitro.


CONCLUSIONS
Both the recombinant protein and plasmid DNA based on HRP2 have different immune characteristics in mice. HRP2 recombinant protein has the potential in practical application.
Li
X
X
Department of Etiology, Fourth Military Medical University, Xi'an 710032.
Miao
J
J
Xue
C F
CF
Zhen
R F
RF
Liu
Z X
ZX
Wang
X F
XF
Mu
S J
SJ
D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis*; D005260:Female; D008213:Lymphocyte Activation; D017780:Malaria Vaccines / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000276:immunology*; D010963:Plasmodium falciparum / Q000276:immunology*; D011506:Proteins / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D019444:Vaccines, DNA / Q000276:immunology*; D000099053:Histidine-Rich Glycoprotein
D000913:Antibodies, Protozoan; D017780:Malaria Vaccines; D011506:Proteins; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D000099053:Histidine-Rich Glycoprotein