Evaluation of protective effect of multi-epitope DNA vaccine encoding six antigen segments of Toxoplasma gondii in mice

Parasitol Res. 2009 Jul;105(1):267-74. doi: 10.1007/s00436-009-1393-1. Epub 2009 Mar 14.

Abstract

To investigate the vaccine potential of multi-epitope vaccines against toxoplasmosis, a multi-epitope DNA vaccine, eukaryotic plasmid pcDNA3.1/T-ME expressing six antigen segments (SAG1(238-256), SAG1(281-320), GRA1(170-193), GRA4(331-345), GRA4(229-245), and GRA2(171-185)) of Toxoplasma gondii was constructed. We investigated the efficacy of pcDNA3.1/T-ME with or without co-administration of a CpG-oligodeoxynucleotide (CpG-ODN) as an adjuvant to protect mice (BALB/c and C57BL/6) against toxoplasmosis. High survival rates were observed in mice immunized with pcDNA3.1/T-ME when challenged with T. gondii RH strain. Lymphocyte proliferation assays, cytokine, and antibody determinations show that mice immunized with pcDNA3.1/T-ME produced stronger humoral and Th1-type cellular immune responses compared to untreated mice or those immunized with empty plasmids. However, co-immunization with CpG-ODN resulted in impaired immune responses. Our data demonstrates that multi-epitope DNA vaccination is a potential strategy for the control of toxoplasmosis and paves the way for further investigations into producing a multi-epitope anti-T. gondii DNA vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / administration & dosage
  • Adjuvants, Immunologic / pharmacology
  • Animals
  • Antibodies, Protozoan / blood
  • Antigens, Protozoan / genetics
  • Antigens, Protozoan / immunology*
  • Cell Proliferation
  • Cytokines / metabolism
  • Epitopes / genetics
  • Epitopes / immunology*
  • Genetic Vectors
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Oligodeoxyribonucleotides / administration & dosage
  • Oligodeoxyribonucleotides / pharmacology
  • Plasmids
  • Protozoan Vaccines / genetics
  • Protozoan Vaccines / immunology*
  • Survival Analysis
  • T-Lymphocytes / immunology
  • Toxoplasma / genetics
  • Toxoplasma / immunology*
  • Toxoplasmosis / prevention & control*
  • Vaccines, DNA / genetics
  • Vaccines, DNA / immunology*

Substances

  • Adjuvants, Immunologic
  • Antibodies, Protozoan
  • Antigens, Protozoan
  • CPG-oligonucleotide
  • Cytokines
  • Epitopes
  • Oligodeoxyribonucleotides
  • Protozoan Vaccines
  • Vaccines, DNA