Demidova, G.V., Zyuzina, V.P., Sokolova, E.P., Borodina, T.N., Bespalova, I.A., Pasyukova, N.I., Tynyanova, V.I.

Toxicity of Yersinia pestis EV76 lipopolysaccharides for mice sensitized by D-galactosamine

Rostov Research Institute for Plague Control, Rostov-on-Don, Russia

Aim. To study toxicity of lipopolysaccharides (LPS28 and LPS 37) of Yersinia pestis for mice sensitized by D-galactosamine (D-GalN). Materials and methods. LPS were obtained by the Westphal method from Y.pestis EV76 strain grown at temperatures of 28 and 37C. Dexamethasone and pentoxifylline were used as immunodepressants. Uridine was used for interruption of D-GalN effect. Results. It was revealed that administration of D-GalN to mice increased their sensitivity to LPS of Y.pestis. Maximal increase in LPS toxicity was observed after simultaneous administration of D-GalN and LPS. D-GalN in dose 20 mg per mouse determined 100% lethality of animals during 24 h after administration of 10 mcg of LPS28 and 25 mcg of LPS37. Uridine in dose of 20 mcg per mouse administered 1 h after LPS and D-GalN neutralized effect of LPS in the presence of D-GalN. Dexamethasone and pentoxifylline did not protect animals sensitized by D-GalN against lethal effect of Y.pestis LPS. Conclusion. It was found experimentally that D-GalN enhances toxic effect of LPS28 in hundreds of times, and non-toxic LPS37 of Y.pestis EV76 demonstrated toxicity comparable to LPS28. Thus the D-GalN model could be used for enhancement of laboratory animals sensitivity to effect of Y.pestis LPS.
Zh. Mikrobiol. (Moscow), 2011, No. 1, P. 7476