Fig 1.
Parasite strain-dependent influence of T lymphocytes on pathogenesis in susceptible BALB/c mice.
BALB/c WT and nude mice were infected with 5×106 stationary phase promastigotes of L. major Friedlin or 5ASKH subcutaneously into the hind footpad. (A) Footpad swelling after L. major infection. Each group contains 8–11 mice. All the data are from normal distribution except data of BALB/c mice at 1 and 3 weeks and BALB/c-nude mice at 2 weeks post-infection of L. major Friedlin have deviated from normal distribution. Data deviated from normal distribution were excluded from statistical comparison (B) Representative photographs of L. major-infected footpads at 6 weeks post-infection. (C) Parasite burden in footpads at 6 weeks post-infection. Each mouse footpad was homogenized in 10 ml culture media and cultured for 3 days then viable promastigotes were counted microscopically. Each group contains four–six mice. Symbols: BALB/c mice infected with L. major Friedlin blue circle or 5ASKH green triangle, BALB/c-nude mice infected with L. major Friedlin black circle or 5ASKH red triangle; Data are the mean ± SEM. Statistical analyses for lesion size by ANOVA. *†¶# means P<0.05 between BALB/c-Friedlin×BALB/c-5ASKH: *; Nude-Friedlin×Nude-5ASKH: †; BALB/c-Friedlin×Nude-Friedlin: ¶ and BALB/c-5ASKH×Nude-5ASKH: #.
Table 1.
Ulcer formation at 6 weeks post-infection with L. major Friedlin or 5ASKH.
Fig 2.
Parasite strain-dependent influence of T/B lymphocytes on pathogenesis in resistant C57BL/6 mice.
C57BL/6 WT and Rag2 KO mice were infected with 5×106 stationary phase promastigotes of L. major Friedlin or 5ASKH subcutaneously into the hind footpad. (A) Footpad swelling after L. major infection. All the data are from normal distribution except data of C57BL/6 mice at 1 week post-infection of L. major Friedlin have deviated from normal distribution. Data deviated from normal distribution were excluded from statistical comparison. Symbols: WT mice infected with L. major Friedlin blue circle or 5ASKH green triangle, Rag2 KO mice infected with L. major Friedlin black circle or 5ASKH red triangle; 3–10 mice per group. (B) Representative photographs of a L. major-infected footpad at 6 weeks post-infection. (C) Parasite burden at 6 weeks post-infection. Each mouse footpad was homogenized in 10 ml culture media and cultured for 3 days then viable promastigotes were counted microscopically. Three–five mice per group. Data are the mean ± SEM. Results are representative of two independent experiments with similar outcomes. *†¶# means P<0.05 between WT-Friedlin×WT-5ASKH: *; Rag2KO-Friedlin×Rag2KO-5ASKH: †; WT-Friedlin×Rag2KO-Friedlin: ¶ and WT-5ASKH×Rag2KO-5ASKH: #.
Fig 3.
L. major Friedlin infection failed to augment the recruitment of macrophages in Rag2 KO mice.
Rag2 KO C57BL/6 mice were infected with 5×106 stationary phase promastigotes of L. major Friedlin or 5ASKH subcutaneously into the hind footpad. At 4 weeks post-infection, cells from the mouse footpads were isolated and analyzed by flow cytometry. The total number (A) and percentages (B) of the cell populations are shown. Four–five mice per group. Data are the mean ± SEM.
Fig 4.
Defective infiltration of neutrophils, eosinophils, and NK cells during L. major Friedlin infection in Rag2 KO mice.
Rag2 KO C57BL/6 mice were infected with 5×106 stationary phase promastigotes of L. major Friedlin or 5ASKH subcutaneously into the hind footpad. At 4 weeks post-infection, cells from the mouse footpads were isolated and analyzed by flow cytometry. The total number (A) and percentages (B) of the cell populations are shown. Four–five mice per group. Data are the mean ± SEM.
Fig 5.
Lower activation of host immune responses by L. major Friedlin infection.
Rag2 KO C57BL/6 mice were infected with 5×106 stationary phase promastigotes of L. major Friedlin or 5ASKH subcutaneously into the hind footpad. At 4 weeks post-infection, cells from mouse footpads were isolated and cultured for 3 days. Culture supernatants were analyzed for (A) IFN-γ, (B) TNF-α, (C) IL-12p40, and (D) IL-10 cytokines by ELISA. Three–four mice per group. Data are the mean ± SEM. *, P<0.05.