Evaluation of Protective Immune Responses Induced by Recombinant TrxLp and ENO2 Proteins againstToxoplasma gondiiInfection in BALB/c Mice.
Toxoplasma gondiiis an obligate intracellular parasitic protozoan that can infect almost all species of warm-blooded animals. As any chemical-based drugs could not act against the tissue cyst stage ofT. gondii, vaccination may be one of the ideal control strategies. In the present study, two new vaccine candidates, named TgENO2 and TgTrxLp, were purified fromEscherichia coliwith pET-30a(+) expression system and then were injected into BALB/c mice to evaluate the protective efficacy against acute and chronic toxoplasmosis. The results showed that both the recombinant proteins, either alone or in combination, could elicit strong humoral and cellular immune responses with a higher level of IgG antibodies, IFN-γ, IL-2, CD4+, and CD8+T cells as compared to those in mice from control groups. After acute challenge with tachyzoites of the GJS strain, mice immunized with rTgTrxLp (8 ± 2.77 d), rTgENO2 (7.4 ± 1.81 d), and rTgTrxLp + rTgENO2 (8.38 ± 4.57 d) proteins showed significantly longer survival time than those that received Freund's adjuvant (6.78 ± 2.08 d) and PBS (6.38 ± 4.65 d) (χ2= 9.687, df = 4,P= 0.046). The protective immunity of rTgTrxLp, rTgENO2, and rTgTrxLp + rTgENO2 proteins against chronicT. gondiiinfection showed 69.77%, 58.14%, and 20.93% brain cyst reduction as compared to mice that received PBS. The present study suggested that both TgENO2 and TgTrxLp were potential candidates for the development of multicomponent vaccines against toxoplasmosis.
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, China.
Meng
M
Wang
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, China.
Xiao-Yu
XY
Yang
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, China.
Nian-Zhang
0000-0001-6368-5519
NZ
Zhang
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, China.
De-Lin
DL
Zhang
State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, China.
Xing-Quan
0000-0003-2530-4628
XQ
Zhu
D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D015800:Protozoan Proteins / Q000276:immunology*; D016052:Protozoan Vaccines / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology / Q000517:prevention & control*
D000913:Antibodies, Protozoan; C000611649:IFNG protein, mouse; D007074:Immunoglobulin G; D007376:Interleukin-2; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D007371:Interferon-gamma