• Vaccine Name: T. cruzi DNA vaccine encoding PFR Ag + IL-12
• Target Pathogen: Trypanosoma cruzi
• Target Disease: Chagas disease
• Type: DNA vaccine
• Status: Research
• Host Species for Licensed Use: Mouse
• Antigen: PFR Ag (Wrightsman and Manning, 2000)
• Immunization Route: Intramuscular injection (i.m.)
• Description: T. cruzi DNA vaccine encoding PFR Ag coadsorbed to alum with either recombinant IL-12 or adenovirus-expressing IL-12. (Wrightsman and Manning, 2000)

Mouse Response

• Vaccination Protocol: Six- to 8-week-old female C57BL/6J mice were immunized by subcutaneous (s.c.) injection with 40 μg PFR protein adsorbed to alum or emulsified with Freund's complete adjuvant. The mice were boosted twice at two-week intervals with 20 μg PFR protein adsorbed to alum or emulsified with Freund's incomplete adjuvant. Alum-PFR Ag mixtures were prepared by combining equal volumes of Rehsorpter aluminum hydroxide adsorptive gel and PFR Ag at 400 μg/ml in 0.9% saline with gentle mixing for 1 h at room temperature. In some experiments murine recombinant IL-12 (rIL-12; a generous gift from Genetics Institute, Cambridge, MA) was mixed with the PFR protein during the adsorption procedure. The amount of rIL-12 added to the mixture gave a final concentration of either 0.5 μg rIL-12/40 μg PFR (initial immunization) or 0.5 μg rIL-12/20 μg PFR (boosts). (Wrightsman and Manning, 2000)
• Immune Response: T cells and CD4+ T cells from mice immunized with either PFR Ag/Freund's or PFR Ag/alum/IL12 secreted high levels of IFN-γ in the presence of macrophages incubated with PFR Ag or macrophages infected with T. cruzi. Only negligible amounts of IFN-γ were observed with the CD8+ T cell population, and no measurable IFN-γ could be detected when any of these T cells were incubated with untreated macrophages. (Wrightsman and Manning, 2000)
• Challenge Protocol: Two weeks after the last injection, mice were challenged with s.c. injection of 102 bloodstream trypomastigotes. Following challenge, mice were checked daily, and survival was recorded at days postinfection. (Wrightsman and Manning, 2000)