Poster 084 - The use of mice as animal model for testing acute toxicity of toxic shock syndrom

Poster 84. Congresso da Sociedade Brasileira de Toxinologia, 8., Symposium of the Pan American Section of the International Society on Toxinology, 8., 2004, Angra dos Reis, Brasil. Abstracts... J. Venom. Anim. Toxins incl.Trop. Dis., 2004, 10, 3, p.443.

The use of Mice as animal model for testing acute toxicity of toxic Shock Syndrom Toxin (TSST-1).

Dias, R.S.^1,5, Carmo, L.S.¹*, Heneine, L.G.D.², Rocha, P.H.², Barbosa, C.F.³, Rodrigues, R.J.³, Linardi, V.R.⁴

1 Laboratório de Enterotoxinas- DIVISA- IOM- FUNED, BH-MG; 2 Laboratório de Imunologia- DCPD- FUNED, BH-MG; 3 Laboratório de Controle Biológico- DCQ- FUNED, BH-MG; 4 Departamento de Microbiologia- ICB- UFMG; 5 Unicentro Izabela Hendrix de Igreja Metodista- BH-MG. Brasil.

Toxic Shock Syndrome is an acute illness, severe and multi-systemic that attacks man when infected by some strains of Staphylococcus aureus producers of TSST-1 toxin that is responsible for the characteristic symptoms of this disease in man. Due to the non- specific mechanism of action on the organism, the use of mice as animal model has been a promising choice to test the endotoxic effects of the shock in vivo. The objective of this research was to verify the sensitivity of the mouse strains BALB/c, C57BL/6 and Switzerland against the acute toxicity of this toxin (LD50). The animals (n = 8-10 animals) were inoculated progressively with increasing doses of toxin (0,01 and 10,0mg/animal) (ip). Four hours later, they were injected again, but with 75mg of E. coli O111:B4 LPS (ip). The acute toxicity was observed during a period of 72 hours. The data were submitted to the variance analysis using the test of Qui - Square (c²). The results and the confidence limits were expressed in toxin/kg. The analysis of the results indicates that the strain BALB/c was the most sensitive (20mg/kg and the trust limits to 95% from 9,0mg/kg to 92,0mg/kg) followed by C57BL/6 (38,5mg/kg and conficence limits to 95% from 9,11 to 401,6mg/kg). The analysis of the data regarding to the strain Switzerland was not conclusive, but it indicates a lower sensitivity. The width of the confidence limits is due to the nature of the toxin and the mechanism of action, via of inoculation and the choice of animal. The selection of the animal model and the standardization of the experiment are fundamental to the development of serum neutralization tests in order to have quality control in the process of vaccine production.