Figure 4
From: Engineering a vector-based pan-Leishmania vaccine for humans: proof of principle
Vaccination with the sand fly-derived DNA chimeric vaccine elicits specific T cell responses against both P. duboscqi and L. longipalpis saliva. BALB/C mice were immunized intradermally in the right ear three times at 2 weeks intervals with 5 µg of VR-2001-SfSPChimera plasmid (crossed circles), or with either L. longipalpis (white circles) or P. duboscqi (crosses) SGH—the equivalent of 1 sand fly salivary gland pairs. Control animals received the same volume of the vehicle solution (PBS; black circles). One month after the last immunization, animals were euthanized, their spleens collected and processed to obtain CFSE-stained splenocytes suspensions. Frequencies of proliferating splenic T cells (total CD3 + and CD3 + /CD4 + or CD3 + /CD8 +) were determined by flow cytometry after 4 days of culture in the presence of BMDCs (5:1 ratio) pulsed with P. duboscqi (A) or L. longipalpis (B) SGH (final concentration of 3 sand fly salivary gland pair/ml). Results from three independent experiments are shown. Each dot represents one animal. Average and SD of the values within each group are shown. Statistical differences are properly identified (One-Way ANOVA with Tukey’s post hoc analysis: *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001 and ****p ≤ 0.0001).
