Effect of highly diluted mice’s serum on murine infection by Trypanosoma cruzi

  • Fabiana Nabarro Ferraz
  • Franciele Karina da Veiga
  • Camila Fernanda Brustolin
  • Angélica Sayuri Mizutani
  • Denise Lessa Aleixo
  • Silvana Marques de Araújo
Keywords: Trypanosoma cruzi, Chagas’ disease, Mice’s serum, Highly diluted medicines


Background: Trypanosoma cruzi biotherapies’ alter the course of experimental infection by this protozoan [1,2], a fact that encourages the evaluation of other highly diluted medicines which modulates host’s immune system. Aim: Evaluate the effect of highly diluted mice’s serum on murine infection by T. cruzi. Methodology: A blind, randomized and controlled study was performed. Animals: 20 male Swiss mice, four weeks old were inoculated intraperitoneally with 1400 blood trypomastigotes Y strain and divided in groups: IC: Infection control - treated with hydroalcoholic solution 7% (n=7); MSI13cH: treated with mice’s serum infected by T. cruzi 13cH (n=6); MSNI13cH: treated with mice’s serum non-infected by T. cruzi 13cH (n=7). Medicines: produced from serum of infected and non-infected mice by T. cruzi in 13cH dynamization [3]. Treatment plan: mice were treated 48 hours before and after infection. Subsequently animals were treated 56/56 hours until 9th day of infection. The medicines were diluted in natural water (1mL/100mL) and offered ad libitum, for 16 consecutive hours. Parasitological and clinical parameters were evaluated. Parasitological: pre-patent and patent period, parasitemia peak, total parasitemia and survival time [4]. Clinical: quantitative - body weight, water and food intake, temperature; qualitative - body hair aspect, edema, movement, diarrhea [5]. Ethics: study was approved by Ethics Committee for Experiments in Animals/UEM. Statistic: data were compared with Mann Whitney test or t Test, significance 5%. Results: MSI13cH showed tendency to increase total parasitemia (p=0.06) and parasitemia peak (p=0.05), with lower patent period (p=0.03) and lower animals survival (p=0.05). MSNI13cH showed no different parasitological parameters from IC (Table 1). MSI13cH and MSNI13cH showed no statistical differences in clinical parameters when compared to IC. These results suggest that highly diluted T. cruzi antibodies present in infected serum administered prior to infection worsen the course of infection by stimulating immunological tolerance via anti-idiotypic antibodies production, which neutralized the activity of anti-T. cruzi antibodies produced by animals [6]. These data need further studies, either by changing treatment plan, or by researching immunological markers involved on suppressor response. Conclusions: MSI13cH worsen murine infection by T. cruzi, with premature death and no alteration in clinical parameters compared to IC.