To verify the role of NKT cells in the αGalCer enhancement of protection induced during DNAp36 priming, groups of NKT deficient BALB/c mice were vaccinated and challenged with Leishmania major: -■-, PBS-NK-T (control) -●- pCINeoDNA and WR-Luc (vector control); -▲-, DNAp36 + VVp36; -∗-, p36DNA+αGalCer + VVp36; also shown is the course of infection for control -◆-, PBS WT-BALB/c mice; (DNAp36 versus DNAp36+ αGalCer p=0.45).
B) Evaluation of parasite burdens at 13 weeks post-infection.
, BALB/c (WT) PBS (control);
, NK-T PBS (Control);
, NK-T pCINeoDNA and WR-Luc (vector control);
, NK-T DNAp36 + VVp36;
, NK-T DNAp36+αGalCer + VVp36. (DNAp36 versus DNAp36+ αGalCer P=0.65) These results are representative of 2 independent experiments. It should be noted that this experiment was performed together with the experiment shown in Figure 5. Hence an enhanced protection was observed for BALB/c mice vaccinated with p36DNA+αGalCer.