Evaluation of _pVAX1-MIC3 as a DNA vaccine against Toxoplasma gondii in mice

Toxoplasmosis is a disease that can infects all warm-blooded animals including livestock, birds and humans that are caused by a parasite named Toxoplasma gondii. It is estimated that 25–30% of total human population worldwide is infected with parasite and carry persistent infection throughout their life. The aim of this study is to identify the potential of pVAX1-mic3 as a recombinant vaccine. The pVAX1-MIC3 is a potent vaccination constructed by the insertion of MIC3 strain of the Toxoplasma gondii into the pVAX1 DNA plasmid. The research was conducted by vaccinating the mice with pVAX1-MIC3 for three times in every interval of two weeks. The toxicity of the vaccine was determined by monitoring the changes in the mice body weight posts vaccination. The specific IgG level was tested by using the ELISA kit. The effectiveness of the vaccination was also tested by challenging the mice with the alive T.gondii and observed for its survival rate. As the result, there are no toxicity effect shown as there are no weight loss observed in mice vaccinated with pVAX1-MIC3. The ELISA test for specific IgG of T.gondii also shown an increase in the concentration of antibody in group vaccinated with pVAX1-MIC3. Lastly, the survival rate of mice vaccinated by pVAX1-MIC3 is increased by 70% compared to unvaccinated group which is 0% survival rate. Thus pVAX1-MIC3 has shown its potential as vaccine against the T. gondii.