Fig. 7.
Comparative analysis of parasitic load and opn transcripts between C57BL/6 and DBA/2 mice in vivo. a. Parasitic load and opn gene expression in C57BL/6+/+ mice, in vivo. Matched evaluation of parasite load fluctuations (black line) by bioluminescence signal, expressed in photons/ sec /ear and RT-qPCR of the relative quantity of opn transcripts (red line) in sites of inoculation. Correlations between parasite load and opn transcripts were as follows: C57BL/6, R Correlation P = 0.0297 and DBA/2 mice, R Correlation P = 0.4618 (data not shown). At each time point a group of 3 representative mice on the basis of parasite load were tested. b. Matched evaluation of the fluctuations in parasite load (bioluminescence) in infection sites, during the first weeks p.i. with L. amazonensis of C57BL/6 (blue bars) and DBA (red bars) mice. Mean values are for 3 representative mice at each time point. A Mann-Whitney test was performed to compare the fold changes between the two groups: *P < 0.05; **P < 0.01. Non-parametric correlation tests (Spearman) were performed to compare Bioluminescence. c-d. Histopathological analysis of primary lesions of C57BL/6 (c) and DBA/2 (d) mice subcutaneously injected with 104 L. amazonensis promastigotes in the right ear pinnae at 80 days p.i. (i) In C57BL/6, L. amazonensis elicited a severe inflammation within the ear dermis, H&E staining, original magnification × 4, scale bar: 250 μm. (ii) Many macrophages were present within the inflammatory infiltrate, F4/80 immunostaining, original magnification × 4, scale bar: 250 μm. (iii) OPN expressing cells were present within the lesion, OPN immunostaining, original magnification × 4, scale bar: 250 μm. (iv) In DBA2, a mild inflammation was noted at the site of inoculation, H&E staining, original magnification × 10, scale bar: 100 μm. (v) A low number of macrophages were present within the lesion, F4/80 immunostaining, original magnification × 10, scale bar: 100 μm. (vi) Very few OPN expressing cells were observed, OPN immunostaining, original magnification × 4, scale bar: 250 μm