• Vaccine Name: T. gondii DNA vaccine pcDNA3.1/MIC11
• Target Pathogen: Toxoplasma gondii
• Target Disease: Toxoplasmosis
• Type: DNA vaccine
• Status: Research
• Host Species for Licensed Use: Human
• Antigen: MIC11 (Tao et al., 2013)
• MIC11 gene engineering:
  • Type: DNA vaccine construction
  • Description: The α-chain of MIC11 gene was PCR amplified and was ligated into pcDNA3.1 vector forming pcDNA/MIC11 plasmid. The plasmid was cloned in E. coli (DH5α strain) and was confirmed by restriction digestion and sequencing analysis. The large scale plasmid extraction was performed using Endo-Free Plasmid Maxi Kit (OMEGA bio-tek, USA) by following the manufacturer's instructions. (Tao et al., 2013)
  • Detailed Gene Information: Click Here.
• Immunization Route: Intramuscular injection (i.m.)
• Description: T. gondii DNA vaccine encoding MIC11 as antigen using pcDNA3.1 vector. (Tao et al., 2013)

Mouse Response

• Host Strain: BALB/c (Tao et al., 2013)
• Host age: 5–6 weeks (Tao et al., 2013)
• Host gender: female (Tao et al., 2013)
• Vaccination Protocol: Sixty BALB/c mice were randomly divided into three groups (20 in each group). 100 μg (for each injection) of pcDNA/MIC11 plasmid or the pcDNA3.1 empty vector were suspended in 100 μl sterile PBS and intramuscularly injected into different groups of mice, respectively. The mice injected with 100 μl sterile PBS only were served as the blank control group. All groups of mice were immunized three times at a 2-week interval using same dosages. (Tao et al., 2013)
• Immune Response: Humoral: higher anti-TLA IgG
  Cellular: higher splenocyte proliferation activity, higher levels of IFN-γ, IL-12, and IL-2
  (Tao et al., 2013)
• Challenge Protocol: Ten days after the last immunization, twelve mice from each group were randomly selected and injected intraperitoneally with 1 × 10^3 tachyzoites of T. gondii RH strain. Tachyzoites were counted with a hemocytometer and adjusted to 5 × 10^3 parasites/ml with 0.1 M PBS (pH 7.4). The parasite solution (200 μl) was injected into each mouse, and mice survival was subsequently monitored daily for 15 days. (Tao et al., 2013)
• Efficacy: The mice immunized with pcDNA/MIC11 showed significantly prolonged survival. All mice in the control groups immunized with PBS or pcDNA3.1 died within 8 or 10 days post-infection, respectively. However, 50 % of the mice immunized with pcDNA/MIC11 were alive at day 10, and 17 % of them survived to day 15 after the parasite challenging. (Tao et al., 2013)