TLR9 and infection: In this study, we evaluate the comparative vaccine potential of DNA/DNA, DNA-prime/Protein-boost, and Protein/Protein based vaccination using gp63 with a toll-like receptor ligand (TLR-9) agonist CpG-ODN in eliciting short- as well as long-lasting immunity against infections with L. donovani in genetically susceptible BALB/c mice.