Protective effect of vaccination with Toxoplasma lysate antigen and CpG as an adjuvant against Toxoplasma gondii in susceptible C57BL/6 mice.
Infection with the intracellular protozoan parasite Toxoplasma gondii causes serious public health problems to both humans and livestock and of great economic impact worldwide. Oligodeoxynucleotides (ODN) which contain immunostimulatory CG motifs (CpG ODN) can promote Th1 responses, an adjuvant activity that is desirable for vaccination against intracellular pathogens. We investigated the feasibility of using CpG as an adjuvant combined with Toxoplasma lysate antigen (TLA) as a vaccine against toxoplasmosis. Genetically susceptible C57BL/6 mice were vaccinated with TLA with or without CpG ODN as an adjuvant and then challenged with 85 cysts of the moderately virulent RRA (Beverley) strain of T. gondii. Prior to challenge infection, immunization with TLA plus CpG ODN directed cellular and humoral immunity toward a Th1 pattern, characterized by enhanced INF gamma production by splenic cells in response to TLA, and enhanced production of toxoplasma-specific IgG and IgG (2a) antibodies. Consequently, CpG/TLA-treated mice showed prolonged survival and 64% reduction in brain parasite burden compared to non-CpG/TLA treated group. Our results suggest that CpG ODN would provide a stable and effective adjuvant for use in vaccination against toxoplasmosis.
El-Malky
Mohamed
M
Department of Molecular Parasitology, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan.
Shaohong
Lu
L
Kumagai
Takashi
T
Yabu
Yoshisada
Y
Noureldin
Mohamed S
MS
Saudy
Niveen
N
Maruyama
Haruhiko
H
Ohta
Nobuo
N
D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000008:administration & dosage; D051379:Mice; D008810:Mice, Inbred C57BL; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology*; D016052:Protozoan Vaccines / Q000008:administration & dosage* / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D014122:Toxoplasma / Q000737:chemistry*; D014123:Toxoplasmosis / Q000276:immunology / Q000517:prevention & control*; D014611:Vaccination
D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides; D016052:Protozoan Vaccines