title: Immunogenicity and protective efficacy of DNA vaccine against visceral leishmaniasis in BALB/c mice.
abstract: The current study was designed to examine the protective efficacy of DNA vaccines based on gp63 and Hsp70 against murine visceral leishmaniasis. Inbred BALB/c mice were immunized subcutaneously twice at an interval of three weeks with pcDNA3.1(+) encoding T cell epitopes of gp63 and Hsp70 individually and in combination. Animals were challenged intracardially with 10(7) promastigotes of Leishmania donovani 10 days post immunization and sacrificed 1, 2 and 3 months post challenge. The immunized animals revealed a significant reduction (P < 0.05) in splenic and hepatic parasite burden as compared to the infected controls. Maximum reduction in parasite load (P < 0.05) was observed in animals treated with a combination of pcDNA/gp63 and pcDNA/Hsp70. These animals also showed heightened DTH response, increased IgG2a, elevated Th1 cytokines (IFN-γ and IL-2) and reduced IgG1 and IL-10 levels. Thus, mice immunized with the cocktail vaccine exhibited significantly greater protection in comparison to those immunized with individual antigens.
authors.affiliation: Parasitology Laboratory, Department of Zoology, Panjab University, Chandigarh 160014, India. puzoology@yahoo.com.
authors.forename: Sukhbir
authors.initials: S
authors.lastname: Kaur
authors.affiliation: Parasitology Laboratory, Department of Zoology, Panjab University, Chandigarh 160014, India. puzoology@yahoo.com.
authors.forename: Tejinder
authors.initials: T
authors.lastname: Kaur
authors.affiliation: Parasitology Laboratory, Department of Zoology, Panjab University, Chandigarh 160014, India.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Joshi
keywords: DNA vaccine; Hsp70; T-cell epitopes; gp63; visceral leishmaniasis