Table 1: Genetically altered live-attenuated vaccine candidates against visceral leishmaniasis.

ParasiteCharacterization of attenuationAnimal modelResults of ImmunizationReferences

L. donovaniBiopterin transporter gene deleted parasite (BT1−/−)BALB/c miceProtective immunity, antigen-specific IFNγ secretion [87]
L. tarentolaeNonpathogenic strain expressing L. donovani A2 antigenBALB/c miceProtective immunity against L. infantum challenge, high IFNγ, low IL-5 [98]
L. donovaniReplication deficient centrin gene deleted (Cen−/−)BALB/c mice, Syrian hamsterProtective immunity against L. donovani and L. braziliensis challenge. Increased IFNγ, IL-2, and TNF producing cells and IFNγ/IL-10 ratio[53]
L. infantumSilent information regulatory 2 single allele deletion (SIR2+/−)BALB/c miceProtective immunity, increased antigen-specific IFNγ/IL-10 ratio[89]
L. donovaniCytochrome c oxidase complex component p27 gene deleted cell line (Ldp27−/−)BALB/c mice12-week survival in host, initial evidence of protective immunity [97] and Dey, unpublished