Immunization with a DNA vaccine encoding Toxoplasma gondii Superoxide dismutase (TgSOD) induces partial immune protection against acute toxoplasmosis in BALB/c mice

BMC Infectious Diseases

Research Article

Xun Li¹  Hua Cong²  Yuan Liu²  Shenyi He²  Huaiyu Zhou²  Yawen Li²  Aiping Cao³ 

[1] Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong Province, People’s Republic of China;Department of Parasitology, School of Medicine, Shandong University, Jinan, Shandong Province, People’s Republic of China;Department of Parasitology, School of Medicine, Shandong University, Jinan, Shandong Province, People’s Republic of China;Present address Department of Clinical Laboratory, The People’s Hospital of Rizhao, Rizhao, Shandong Province, People’s Republic of China;

关键词: Toxoplasma gondii;    ME49 strain;    Superoxide dismutase;    DNA vaccine;    BALB/c mice;   

DOI  :  10.1186/s12879-017-2507-5

 received in 2016-11-02, accepted in 2017-05-30,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundToxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects all warm-blooded animals including humans and causes toxoplasmosis. An effective vaccine could be an ideal choice for preventing and controlling toxoplasmosis. T. gondii Superoxide dismutase (TgSOD) might participate in affecting the intracellular growth of both bradyzoite and tachyzoite forms. In the present study, the TgSOD gene was used to construct a DNA vaccine (pEGFP-SOD).MethodsTgSOD gene was amplified and inserted into eukaryotic vector pEGFP-C1 and formed the DNA vaccine pEGFP-SOD. Then the BALB/c mice were immunized intramuscularly with the DNA vaccine and those injected with pEGFP-C1, PBS or nothing were treated as controls. Four weeks after the last immunization, all mouse groups followed by challenging intraperitoneally with tachyzoites of T. gondii ME49 strain.ResultsResults showed higher levels of total IgG, IgG2α in the sera and interferon gamma (IFN-γ) in the splenocytes from pEGFP-SOD inoculated mice than those unvaccinated, or inoculated with either empty plasmid vector or PBS. The proportions of CD4+ T cells and CD8+ T cells in the spleen from pEGFP-SOD inoculated mice were significantly (p < 0.05) increased compared to control groups. In addition, the survival time of mice immunized with pEGFP-SOD was significantly prolonged as compared to the controls (p < 0.05) although all the mice died.ConclusionThe present study revealed that the DNA vaccine triggered strong humoral and cellular immune responses, and aroused partial protective immunity against acute T. gondii infection in BALB/c mice. The collective data suggests the SOD may be a potential vaccine candidate for further development.

【 授权许可】

CC BY   
© The Author(s). 2017