title: Electrophoretic Patterns of Toxoplasma gondii Excreted/Secreted Antigens and Their Role in Induction of the Humoral Immune Response.
abstract: BACKGROUND
  Toxoplasma gondii is an obligatory intracellular protozoan parasite on which studies are pending regarding production of vaccine. To date, the production of human vaccine has not been successful where approximately one third of the world's population is thought to be infected with T. gondii.
  
  
  OBJECTIVE
  The present study was designed to compare the electrophoretic patterns of T. gondii excreted/secreted antigens (ESAs) and determine their role in the stimulation of the humoral immune response.
  
  
  METHODS
  T. gondii ESAs were prepared from cell cultures (albino rat fibroblast) and cell-free mediums (RPMI-1640). Next, the SDS-PAGE technique was used for comparing molecular weights of the antigens. Forty C57BL/6 mice were divided randomly into four groups (n = 10). Immunization was performed subcutaneously at an interval of 2 weeks in two groups by injecting 100 µg of each of the above-mentioned antigens. Two groups, as negative control, also received fibroblast lysate proteins or adjuvant separately. All of the groups were then challenged with the T. gondii RH strain. Serum samples were collected from all mice and measured by immunoblotting technique for detection of immunogenic antigens.
  
  
  RESULTS
  The electrophoretic mobility of the prepared antigens/proteins from cell culture, cell-free media, Fibroblast Lysate Proteins and Toxoplasma Lysate Antigens (TLA) showed 13, 12, 8 and 8 bands, respectively. The case groups, in challenge with T. gondii (RH strain), showed more survival prolongation than the control groups. Furthermore, the survival period was identical for both case groups with a tendency for slightly higher survival of mice receiving ESA from cell-free medium. Analysis of sera by immunoblotting also revealed one band of 65 KDa in sera from both case groups.
  
  
  CONCLUSIONS
  We suggest that this band be extracted and its amino acids sequence determined to produce Synthetic Polypeptide for immunization studies.
authors.affiliation: Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Daryani
authors.affiliation: Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Sharif
authors.affiliation: Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Hamed
authors.initials: H
authors.lastname: Kalani
authors.affiliation: Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Rafiei
authors.affiliation: Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Kalani
authors.affiliation: Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, IR Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Ahmadpour
keywords: Immunization; Immunoblotting; Toxoplasma