• Vaccine Name: pVAX1-C-Cp12-Cp21
• Target Pathogen: Cryptosporidium parvum
• Target Disease: Cryptosporidiosis
• Type: DNA vaccine
• Status: Research
• Host Species for Licensed Use: Human
• Antigen: Cp12 (Yu et al., 2010): a 12kDA surface adherence protein of C.parvum (Yao et al., 2007);Cp21: a 21kDA surface adherence protein of C.parvum (Yu et al., 2010):
• Cp12 gene engineering:
  • Type: DNA vaccine construction
  • Description: Amplified by PCR using a forward primer containing the booster sequence encoding for CpG-ODN. The amplified C-Cp12 was linked to Cp21 and formed C-Cp12-Cp21, and was inserted into the pVAX1 expression vector. (Yu et al., 2010)
  • Detailed Gene Information: Click Here.
• Cp21 gene engineering:
  • Type: DNA vaccine construction
  • Description: Amplified by PCR using a forward primer containing a synthetic linker sequence. The amplified Cp21 with the linker sequence was inked to C-Cp12 and formed C-Cp12-Cp21, and was inserted into the pVAX1 expression vector. (Yu et al., 2010)
  • Detailed Gene Information: Click Here.
• Immunization Route: Intramuscular injection (i.m.) or Nasal spray
• Description: C. parvum DNA vaccine that express Cp12 and Cp21 in pVAX1 as antigen and use CpG-ODN as adjuvant. (Yu et al., 2010)

Mouse Response

• Host Strain: BALB/c mice (Yu et al., 2010)
• Host age: 5–7-week-old (Yu et al., 2010)
• Vaccination Protocol: Two hundred mice were randomly divided into 10 groups. Mice in different groups were immunized at weeks 0, 3, and 5 with different schemes: 1) 100 μg of pVAX1-CP12 musculature, 2) 100 μg of pVAX1-CP21 musculature, 3) 100 μg of pVAX1-CP12 nasal, 4) 100 μg of pVAX1-CP21 nasal, 5) 100 μg of pVAX1-CP12-CP21 musculature, 6) 100 μg of pVAX1-C-CP12-CP21 musculature, 7) 100 μg of pVAX1-CP12-CP21 nasal, 8) 100 μg of pVAX1-C-CP12-CP21 nasal, 9) 100 μg of pVAX1, 10) 0.1mL of PBS (Yu et al., 2010)
• Immune Response: Humoral: pVAX1-C-Cp12-Cp21 nasal spray group had significantly higher level of IgG compared to pVAX1 vector group and PBS group (P < 0.01). The IgG level in the pVAX1-C-Cp12-Cp21 nasal spray group was also higher than that of pVAX1-Cp12, pVAX1-Cp21, and pVAX1-Cp12-Cp21 group but was not significant.
  Cellular: The percentages of CD4+ T cells in pVAX1-C-Cp12-Cp21 nasal group were significantly higher than that in the groups treated with pVAX1 vector, PBS, pVAX1-Cp12, and pVAX1-Cp21 (P < 0.01). The percentages of CD8+ T cells in pVAX1-C-Cp12-Cp21 nasal spray group was significantly higher than that in the PBS group (P < 0.01). (Yu et al., 2010)
• Challenge Protocol: Each mouse was orally inoculated with 1 × 10^6 C. parvum oocysts in 0.5 ml of water 2 weeks after the last immunization. (Yu et al., 2010)
• Efficacy: Mice in pVAX1-Cp12-Cp21 and pVAX1-C-Cp12-Cp21 groups excreted less numbers of oocysts than that in other groups (P < 0.05). Mice in the pVAX1-C-Cp12-Cp21 nasal spray group have a 77.5% reduction in the level of oocysts shedding. (Yu et al., 2010)