• Vaccine Name: pVAX-P1 DNA vaccine
• Target Pathogen: Leishmania donovani
• Target Disease: Visceral leishmaniasis
• Vaccine Ontology ID: VO_0004272
• Type: DNA vaccine
• Status: Research
• Antigen: P1 gene of Leishmania donovani (Arora et al., 2011).
• P1 gene engineering:
  • Type: DNA vaccine construction
  • Description: The purified full-length ORF cloned non-directionally in pGEMT-Easy vector was digested out and then directionally sub-cloned in pVAX1 vector (Invitrogen, USA). The purified plasmid DNA containing full-length ORF was confirmed by DNA sequencing also. The plasmid DNA was made endotoxin-free by using Endofree Plasmid DNA Mega Purification Kit (Qiagen, Hilden, Germany) according to the manufacturer’s instructions. The endotoxin free plasmid DNA (termed pVAX-P1) was used for the immunization of animals as DNA vaccine (Arora et al., 2011).
  • Detailed Gene Information: Click Here.
• DNA vaccine plasmid:
  • DNA vaccine plasmid name:
  • DNA vaccine plasmid VO ID: VO_0000024
• Immunization Route: Intramuscular injection (i.m.)
• Description: pVAX-P1 DNA vaccine, given in prime-boost mode is protective against L. donovani (Arora et al., 2011).

Hamster Response

• Host Strain: Syrian golden
• Vaccination Protocol: Six weeks old Syrian golden hamsters (Mesocricetus auratus) were immunized in the following groups, with 6 hamsters per group. Group I: Naïve animals (Unimmunized – uninfected) were given PBS only and not challenged, group II: Animals were immunized with recombinant protein vaccine, rLdP1 (50 μg) along with Complete Freund’s adjuvant and two booster doses of same amount of antigen given with Incomplete Freund’s adjuvant, group III: Hamsters immunized with plasmid DNA vaccine alone, pVAX1-P1 single dose, group IV: Hamsters immunized with pVAX-P1 and given a prime-boost dose after 15 days, group V: Hamsters immunized with pVAX1-vector only and group VI: Unimmunized – were given PBS only (Arora et al., 2011).
• Challenge Protocol: All the animals except group I, were challenged with 1 × 10^7 promastigotes (from late log-phase axenic cultures) intracardially (i.c.) on day 28. The hamsters were observed for 6–8 weeks post challenge (p.c.). At the end of 10 weeks post infection, the surviving animals were euthanized and parasitological and immunological parameters were studied (Arora et al., 2011).
• Efficacy: Prime-boost immunization with pVAX-21 DNA vaccine resisted the increase in spleen parasite burden by 75.68% (Arora et al., 2011).