Safety of gentamicin-attenuated Leishmania infantum in domestic dogs

Introduction and Objectives: Leishmania infantum (L. infantum), a causative agent of canine visceral leishmanias (CVL). The parasite is located visceral organs of dog including in the spleen and liver. There has been much interest in attempts to vaccinate against L. infection, because leishmanicidal drugs are cost and drug resistances have been reported. We reported that the attenuated line of L. infantum is safe and no clinicopathological changes induced following injection of the attenuated line of L. infantum in German shepherd dogs. In the present study, we showed no clinical signs of CVL were found in the domestic dogs. Methods and Materials: Parasites: Promastigotes of L. infantum were cultivated in complete RPMI (GIBCO) supplemented with 10% FCS and incubated at 25o C in air for 7 days. The stationary phase of promastigotes was harvested and a suspension with concentration of 5 x 108 cells/ml in PBS were prepared. Dogs: Two dogs were injected intravenously (i.v.) with 100 ml of this suspension per kg of body weight. The experiment was terminated after twelve months and the clinical signs of disease were recorded. Results: None of the dogs showed any abnormalities and clinical signs of disease during the observation period. In addition, no histopathological changes were seen in the liver and spleen of the dogs. Conclusion: The gentamicin-attenuated line of L. infantum is safe in the mixed bread dogs.

Keywords:

Gentamicin- attenuated line of Leishmania infantum , vaccine , safety , dog