Résumé
We studied the feasibility of using halloysite clay nanotubes (HNTs) and carboxyl-functionalised multi-walled carbon nanotubes (COOH-MWCNTs) as antigen carriers to improve immune responses against a recombinant LipL32 protein (rLipL32). Immunisation using the HNTs or COOH-MWCNTs significantly increased the rLipL32-specific IgG antibody titres (p < 0.05) of Golden Syrian hamsters. None of the vaccines tested conferred protection against a challenge using a virulent Leptospira interrogans strain. These results demonstrated that nanotubes can be used as antigen carriers for delivery in hosts and the induction of a humoral immune response against purified leptospiral antigens used in subunit vaccine preparations.
Sujets)
Hydrates de carbone alimentaires/analyse , Fibre alimentaire/analyse , Qualité alimentaire , Contrôle des aliments/méthodes , Fruit/composition chimique , Modèles biologiques , Malus/composition chimique , Calibrage , Produits agricoles/composition chimique , Produits agricoles/croissance et développement , Produits agricoles/métabolisme , Danemark , Hydrates de carbone alimentaires/métabolisme , Fibre alimentaire/métabolisme , Stockage des aliments , Aliment génétiquement modifié , Fruit/croissance et développement , Fruit/métabolisme , Méthode des moindres carrés , Modèles linéaires , Malus/croissance et développement , Malus/métabolisme , Analyse de régression , Reproductibilité des résultats , Solubilité , Spectroscopie proche infrarougeRésumé
Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR) analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50) was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.