The anti-proliferative effects were assessed on the growth of L. infantum promastigotes previously exposed for 30 min to serum samples from placebo (n = 5) and vaccinated dogs [rPSA (n = 9) or Cter-rPSA (n = 5)], collected before immunization and at 2 months post-vaccination, and then washed and cultured for 3 days at 25°C in 5 mL of RPMI medium supplemented with 20% foetal calf serum (FCS). At day 3, parasites were counted by flow cytometry (FACSCanto, Becton Dickinson) to assess cellular viability and parasite concentration. Results are expressed in percentage of promastigote growth inhibition +/- standard deviation (* p<0.05, ** p<0.01, *** p<0.001).