Vaccination of Balb/c mice against experimental visceral leishmaniasis with the GP36 glycoprotein antigen of Leishmania donovani

Cross-Protective Efficacy of a ProphylacticLeishmania donovaniDNA Vaccine against Visceral and Cutaneous Murine Leishmaniasis

“…The FML and recombinant NH36 antigens have been shown to induce significant protection against the agents of visceral leishmaniasis (L. donovani and L. chagasi) in a variety of animal models (5,13,40,50,51). A major finding of the present study is that these L. donovani antigens are also immunogenic against L. mexicana and can induce significant heterologous protection against this species, particularly when administered as a DNA vaccine.…”

“…The higher immunogenicity of FML versus NH36 may be due to additional epitopes present in this complex. Also, the FML and its GP36/NH36 glycoprotein antigen were purified (35,40) and cloned from L. donovani (48). NH36 sequences present 96.2% similarity between L. donovani and L. major (48), although a very species-specific response to both FML and NH36 antigen was observed in murine macrophageLeishmania in vitro interactions (36) and serology (39).…”

“…Female BALB/c mice (6 to 8 weeks old) were used in all experiments. For the evaluation of vaccine efficacy against visceral leishmaniasis, mice were immunized with either three subcutaneous (s.c.) doses of 100 g of purified FML or 100 g of rNH36 with 100 g of saponin as adjuvant, one week apart as previously reported (40,50,51) or via intramuscular with 100 g of VR1012-NH36 plasmid DNA in 100 l of saline solution and boosted 2 weeks later by a second injection (15). Control groups included the empty VR1012 vector and saline solution.…”

“…The fucose-mannose ligand (FML) complex of L. donovani has been characterized as a major antigenic complex of this parasite species (35,36), and its most immunogenic fraction, a glycoprotein of 36 kDa (40), has a proteic moiety identified as nucleoside hydrolase 36 (NH36) (48). NHs participate in parasite DNA metabolism, hydrolyzing the N-glycosidic bond of purine and pyrimidine ribosides to yield the ribose and base, and are present in a wide variety of Trypanosomatidae parasites (12,18,31,42).…”

“…NHs participate in parasite DNA metabolism, hydrolyzing the N-glycosidic bond of purine and pyrimidine ribosides to yield the ribose and base, and are present in a wide variety of Trypanosomatidae parasites (12,18,31,42). Both the purified FML complex and NH36 can induce strong immune responses and significant protection against L. donovani infection in mouse models (50,51,40). FML in saponin formulation has also been shown to protect dogs in field trials as a prophylactic (5,13) or therapeutic vaccine (6).…”