• Vaccine Ontology ID: VO_0011489
• Type: DNA vaccine
• Status: Research
• Antigen: Canine distemper virus fusion and hemagglutinin antigens
• CDVgp5 gene engineering:
  • Type: DNA vaccine construction
  • Description: The Onderstepoort strain CDV HA and F cDNAs were amplified by PCR from a recombinant canarypox virus DNA using, respectively, primers pairs LF185 (5′-ATCGTCTCTAGAATGCTCCCCTACCAA-3′)/LF186 (5′-ATCGTCCGCCGCGGTTAACGGTTACATGAG-3′) and LF187 (5′-CTCGAGTCTAGAATGCACAAGGGAATCCCC-3′)/LF188 (5′-ATCCTGCCGCGGTCAGTGTGATCTCACATAGGATTT-3′). Five micrograms of purified CAV2 DNA were transfected into MDCK cells using Lipofectamine as described by the manufacturer (Gibco Lifesciences). After 24 h of incubation at 37 °C, the serum free medium was removed and replaced by supplemented MEM medium. The culture was incubated at 37 °C for 8 days with supplemented MEM medium being added to it on the third day(Fischer et al., 2002).
  • Detailed Gene Information: Click Here.
• CDVgp6 haemagglutinin protein H gene engineering:
  • Type: DNA vaccine construction
  • Description: The Onderstepoort strain CDV HA and F cDNAs were amplified by PCR from a recombinant canarypox virus DNA using, respectively, primers pairs LF185 (5′-ATCGTCTCTAGAATGCTCCCCTACCAA-3′)/LF186 (5′-ATCGTCCGCCGCGGTTAACGGTTACATGAG-3′) and LF187 (5′-CTCGAGTCTAGAATGCACAAGGGAATCCCC-3′)/LF188 (5′-ATCCTGCCGCGGTCAGTGTGATCTCACATAGGATTT-3′). Five micrograms of purified CAV2 DNA were transfected into MDCK cells using Lipofectamine as described by the manufacturer (Gibco Lifesciences). After 24 h of incubation at 37 °C, the serum free medium was removed and replaced by supplemented MEM medium. The culture was incubated at 37 °C for 8 days with supplemented MEM medium being added to it on the third day (Fischer et al., 2002).
  • Detailed Gene Information: Click Here.
• Vector: pCAT basic vector (Promega)
• Immunization Route: Intranasal

Dog Response

• Vaccination Protocol: Dogs of group A were vaccinated on days 0 and 21 via the intranasal route with a mixture containing 105.8 TCID50/ml of vCA13 and 105.8 TCID50/ml of vCA17. Each nostril was infused with 0.5 ml of the vaccine solution. Dogs of group B were vaccinated on days 0 and 21 by the subcutaneous route (1 ml) with an non-relevant vaccine which did not contain CDV and/or CAV2 antigens. Experiment 2: Vaccinations were done with the same experimental design as in experiment 1, with the following exceptions: (1) all vaccinations were performed on days 0 and 28. Dogs of group A and B were vaccinated with 1 ml of a mixture of vCA13 and vCA17 containing 2×10^7 TCID50/ml of vCA13 and 2×107 TCID50/ml of vCA17; and (2) group C remained unvaccinated (Fischer et al., 2002).
• Challenge Protocol: All dogs were challenged intravenously with the virulent NVSL strain of CDV on day 42 after receiving an intramuscular administration of diphenhydramine hydrochloride at 1 mg/lb. Challenge consisted of 10 ml (0.5 ml of 1:10 NVSL CDV stock diluted with 9.5 ml of cold PBS) administered intravenously into the cephalic vein. All dogs were observed daily for 2 days until 21 days after challenge to record morbidity and/or mortality (Fischer et al., 2002).
• Efficacy: The intranasal vaccination with a mixture of both recombinant CAV2s provides an excellent level of protection in seronegative puppies, confirming the value of replication-competent adenovirus-based vectors for mucosal vaccination (Fischer et al., 2002).