• 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.
• Vector: pCP15/60 (Jenkins et al., 1999)
• Immunization Route: Parenchymal injection

• Vaccine Ontology ID: VO_0011362
• Type: DNA vaccine
• Status: Research
• Antigen: Cp23 antigen
• CP23 gene engineering:
  • Type: DNA vaccine construction
  • Description: The C. parvum 27-kDa antigen coding sequence (GenBank accession number U34390) was amplified from a Cp23- pGEX 4T-2 clone. The fragment was cloned into the EcoRI and NotI restriction enzyme sites of the pUMVC4b expression vector (Adevron, Fargo, ND, USA). This vector has a cytomegalovirus promoter and immunoadjuvant site that enhances immune responses. Plasmids containing inserts (pUMVC4b-Cp23) and plasmids without inserts (pUMVC4b) were transformed into UltraMAX™ DH5a-FT™ Competent Cells (Invitrogen, Carlsbad, CA, USA), purified, and dissolved in sterile Tris–borate–ethylenediamine tetraacetic acid (TBE). After cloning, the sequence of the resulting clone was confirmed by automated DNA sequencing (Ehigiator et al., 2007).
  • Detailed Gene Information: Click Here.
• Vector: pUMVC4b expression vector
• Immunization Route: Subcutaneous injection

• Type: DNA vaccine
• Status: Research
• Host Species for Licensed Use: Human
• Antigen: CpP2: acidic ribosomal proteins P2 of C. parvum (Benitez et al., 2011)
• CpP2 gene engineering:
  • Type: Recombinant vector construction
  • Description: CpP2 antigen coding sequence was amplified by PCR and was ligated into the EcoRI and NotI restriction enzyme sites of the pUMVC4b expression vector. The ligation mix was then transformed into UltraMAX™ DH5a-FT™ Competent Cells and were selected on LB agar containing kanamycin (50 μg/ml). (Benitez et al., 2011)
  • Detailed Gene Information: Click Here.
• Vector: pUMVC4b (Benitez et al., 2011)
• Immunization Route: Intramuscular injection (i.m.)

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).

Mouse Response

• Host Strain: C57BL/6 KO
• Vaccination Protocol: Mice (ten per group) were injected subcutaneously in the ear with 100-μg plasmid pUMVC4b-Cp23 in TBE on days 0, 14, and 29. Mice in the control group were injected with either the vector pUMVC4b without the insert or with PBS (Ehigiator et al., 2007).
• Challenge Protocol: The different treatment groups of IL-12p40KO mice were challenged with a dose of 1,000 C. parvum oocysts by oral gavage 2 weeks after the last immunization (Ehigiator et al., 2007).
• Efficacy: Cp23-DNA vaccination induced a 50-60% reduction in oocysts shedding, indicating a partial protection against C. parvum infection in IL-12 KO mice (Ehigiator et al., 2007).
• Host Ighg1 response
  • Description: Six weeks post immunization, mice were bled and antibody responses were measured by ELISA. IgG1 responses were significantly higher in Cp23 vaccinated mice than vector (control) immunized mice (Ehigiator et al., 2007).
  • Detailed Gene Information: Click Here.
• Host Ighv1-9 response
  • Description: Six weeks post immunization, mice were bled and antibody responses were measured by ELISA. IgG2a responses were significantly higher in Cp23 vaccinated mice than vector (control) immunized mice (Ehigiator et al., 2007).
  • Detailed Gene Information: Click Here.

Mouse Response

• Host Strain: C57BL/6 interleukin-12p40 (IL-12p40) knockout (KO) mice (Benitez et al., 2011)
• Vaccination Protocol: Mice (10 per group) were injected with 100 μg plasmid pUMVC4b-CpP2 in TBE on days 0, 14, and 29. After primary immunization, mice in prime-boost regime were immunized with 3 μg of rP2 in Hunter’s TiterMax:PBS on days 43 and 57. The control group mice were injected with the empty pUMVC4b vector. (Benitez et al., 2011)
• Immune Response: Humoral: Anti-P2 antibody response was detected four weeks after primary dose injection and two weeks after the first booster dose injection. The response was further enhanced after the injection of the third dose. The anti-CpP2 antibody response was not observed in the control. Poor responses to the recombinant plasmid in wildtype mice were observed. Only IgG1 response was induced. IgG2a and IgA responses were not observed. (Benitez et al., 2011)
  Cellular: Stimulation of splenocyte cultures from immunized mice with different concentrations of rCpP2 protein resulted in a dose-dependent proliferative response. Increased levels of IFN-γ were observed in splenocyte cultures from immunized mice compared with both groups of controls (P<0.05). (Benitez et al., 2011)
• Challenge Protocol: The different treatment groups were challenged with a dose of 1 × 10^3 C. parvum oocysts by oral gavage 2 weeks after the last immunization. (Benitez et al., 2011)