• Vaccine Name: C. parvum DNA vaccine encoding CP15/60
• Target Pathogen: Cryptosporidium parvum
• Target Disease: Cryptosporidiosis
• Vaccine Ontology ID: VO_0011502
• Type: DNA vaccine
• Status: Research
• Antigen: C. parvum sporozoite surface antigen CP15/60
• CP15/60 gene engineering:
  • Type: DNA vaccine construction
  • Description: Recombinant pCP15/60 plasmid DNA was prepared using standard procedures and resuspended to 1 mg/ml in 0.15 M NaCl. Sera was collected from multiparous Holstein–Fresian cows at 8–12 weeks prior to parturition and tested by IFA for presence of Ab to C. parvum oocysts (Jenkins et al., 1999).
  • Detailed Gene Information: Click Here.
• DNA vaccine plasmid:
  • DNA vaccine plasmid name:
  • DNA vaccine plasmid VO ID: VO_0005029
• Immunization Route: Parenchymal injection

Mouse Response

• Host Strain: C57BL/6NCr
• Vaccination Protocol: Cows (n=2) with negligible titers (<1:50) to C. parvum oocysts were immunized at 6, 4 and 2 weeks prior to parturition with 1 mg of plasmid DNA by needle-syringe injection into the parenchymal tissue of the mammary gland. Colostrum from the cows was also tested for conferring passive immunity against C. parvum infection by oral administration to immunosuppressed adult inbred mice. Immune colostrum and control colostrum were administered to separate groups of dexamethasone (DEX)-treated adult C57BL/6NCr mice beginning 12 h before and at 12 h intervals for 3 days after oral C. parvum oocyst infection (Jenkins et al., 1999).
• Challenge Protocol: In three separate experiments, DEX-treated mice (n=4 per group, six groups per treatment) received 250 μl of HBC or NBC by gastric intubation using a 26 ga. gavage needle 12 h prior to C. parvum infection. At 0 h, the mice were infected with either 103 or 104 C. parvum oocysts and given 250 μl of either HBC or NBC. Control mice were given H₂O and either infected or not infected with C. parvum oocysts (Jenkins et al., 1999).
• Efficacy: Mice receiving immune colostrum showed partial protection (about 50% reduction) against intestinal C. parvum development compared to mice receiving control colostrum. This protection was evident at a challenge dose of 10^3 C. parvum oocysts per mouse (Jenkins et al., 1999).