Figure 1From: Leishmania braziliensis and Leishmania amazonensis amastigote extracts differ in their enhancement effect on Leishmania infection when injected intradermallyEffect of intradermal injection of L. amazonensis (LaE) and L. braziliensis (LbE) extracts in the infection of BALB/c mice by L. braziliensis . A and C, lesion sizes in groups of five to eight BALB/c mice injected with saline and different doses of LaE (A) or LbE (C). B and D, number of parasites per lesion as estimated by limiting dilution, at the sixth week after infection, of the same mice whose lesion sizes are depicted in A and C, respectively. The animals were treated with a single intradermal injection of saline or of the doses of extracts indicated above the graphs in A and C or below the X axis in B and D. One week later they were infected with 107 L. braziliensis promastigotes in the stationary phase of growth. The lines in A and C join the median values of the results from each group in each week, and the vertical bars represent the interquartile interval. Each symbol in B and D represents the result obtained from a single animal. The results of two independent experiments are shown. Symbols and lines corresponding to the results from one experiment are dark blue and the lines are broken; from the other experiment the symbols and lines are red and the lines are continuous. Comparisons between the groups of extract-injected and the group of saline-injected mice were performed by Mann–Whitney U test [level of significance when comparing lesion sizes (A and C) = 0.0056; when comparing lesion parasitism (B and D) = 0.0167]. *P < 0.005; **P < 0.001.Back to article page