Schistosoma mansoni antigenic extracts obtained by different extraction procedures

Abstract

Solubilization of Schistosoma mansoni antigens was obtained by agitation of adult worms in a 3M KCl solution. The protein contents of the KCl extrats varied from 0.35 to 0.96 mg/ml. Sera from 97 patients with hepatointestinal shistosomiasis and viable eggs in stools from a Brazilian endemic area were studied by immunoelectroomophoresis and Ouchterlony immunodiffusion methods with the KCl extract and with another antigen, obtained by homogenization of adult schistosomes in saline. The rate of positiveness of immunoprecipitation deterctions by immunoelectroomophoresis with the KCl extract was 53.5%. A correlation was verified between methods of detection and extration procedures, resulting in a better association of the extract obtained by agitation in 3M KCl and immunoelectroomophoresis.<br>Foi obtida a solubilização de antígenos do Schistosoma mansoni por agitação de vermes adultos em solução de KCl 3M. O teor protéico dos extratos de KCl variou de 0,35 a 0,96mg/ ml. Foram testados pelos métodos de imunoeletroosmoforese (IEOP) e dupla imunodifusão (Ouchterlony), 97 soros de doentes de area endêmica brasileira de esquistossomose, forma clínica hepatointestinal e com exames coprológicos positivos para S. mansoni, com o extrato de KCl e outro antígeno obtido pela homogenização de vermes adultos em salina. A taxa de positividade das reações de imunoprecipitação por IEOP com o antígeno extraído pela ação do KCl 3M foi 53,5%. Foi verificada a correlação entre os métodos de detecção e de extração resultando numa melhor associação entre o extrato obtido por agitação no KCl 3M e a IEOP

Current Status of the Sm14/GLA-SE Schistosomiasis Vaccine: Overcoming Barriers and Paradigms towards the First Anti-Parasitic Human(itarian) Vaccine

“…Rather than lyophilized parasites, generally used by other research groups, a saline extract containing secreted/excreted antigens derived from living adult schistosomes was utilized for initial immunizations. The restricted number of potential protective antigens released in this saline extract allowed an accelerated identification of strong antigen candidates for molecular analysis and gene cloning [18,19,20,21,22]. Innovative methods were also adopted for the assessment of immunity, where the use of outbred models, in contrast to the commonly-employed inbred animals, allowed a better representation of the ultimate target population and provided a unique opportunity to develop an alternative strategy for the assessment of protective immunity.…”

Preliminary analysis of Sm14 in distinct fractions of Schistosoma mansoni adult worm extract

“…Living worms were then allowed to stand at room temperature (28ºC to 30ºC) in fresh PBS (phosphate buffered saline) for 2-3 h, and frozen at -20ºC. After thawing, PBS suspensions of the worms (1g worms/10 ml PBS) were filtered through a wire mesh, and centrifuged at 10,000 g for 1 h at 4ºC (Tendler & Scapin 1981, Tendler et al 1982. The protein content of SE was assessed by Lowry's method (Lowry et al 1951), and stock batches containing 1 mg/ml were stored at -20ºC.…”

Current Status of the Sm14/GLA-SE Schistosomiasis Vaccine: Overcoming Barriers and Paradigms towards the First Anti-Parasitic Human(itarian) Vaccine

“…Instead of lyophilized parasites, generally used by other groups, a saline extract containing secreted/excreted antigens derived from living adult schistosomes was obtained for the initial immunizations. The restricted number of potential protective antigens released in this saline extract, allowed a more direct identification of strong candidates for the following molecular phase of the development[18][19][20][21][22]. Innovative methods were also adopted in the experimental phase, when the use of outbred models, in contrast to the commonly employed inbred animals, allowed a better representation of the ultimate target population and provided a unique opportunity to develop an alternative strategy for the protection assessment, improving the overall understanding of the outcomes.…”