BLT₁ expression on C57BL/6 (A) and 129/Sv (B) macrophages.

<p>The resident cells were obtained as described in the Material and Methods, and the expression of the higher affinity receptor for LTB₄ was evaluated by flow cytometry. The mononuclear population was gated using the forward/side scatters and analyzed to determine the fluorescence intensity on the cells. The numbers in the histograms indicate the percentage of cells expressing the BLT₁ receptor. The results shown are from one experiment and are representative of two independent experiments.</p

Effect of exogenous LTB₄ on the phagocytosis of yeast by C57BL/6 and 129/Sv macrophages.

<p>PMs from C57BL/6 (A) and 129/Sv (B) mice were incubated for 2 h with IgG-opsonized or non-opsonized yeast at a yeast-to-cell ratio of 1∶5 in the presence or absence of exogenous LTB₄. The data are expressed as the mean ± SEM from one representative experiment of a total of two experiments (n = 3 to 5). *sv129 compared with C57BL/6; ^#129/Sv and C57BL/6 compared to LTB₄ treatment. p<0.05 was considered significant.</p

Differential leukocyte recruitment to the lung in resistant (129/Sv) and susceptible (C57BL/6) mice.

<p>Cells were obtained from mice at 7 and 14 days after i.t. injection of PBS or 5×10⁵<i>H. capsulatum</i> yeast cells, as described in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0085083#s3" target="_blank">Materials and Methods</a> section. The total cells (A), neutrophils (B) and mononuclear cells (C) were enumerated and identified after Rosenfeld staining. The data are expressed as the mean ± SEM from one representative experiment of a total of three experiments (n = 6/each experiment). *C57BL/6 and sv129 compared with PBS; ^#C57BL/6 compared with sv129. p<0.05 was considered significant.</p

Survival rate and fungal burden in <i>H. capsulatum</i>-infected C57BL/6 and 129/Sv mice.

<p>C57BL/6 and sv129 mice were infected i.t. with 1×10⁶ (A) or 5×10⁵ (B) yeast cells, and their survival was followed for 60 days (n = 6). The fungal loads in the lungs (C) and spleen (D) of mice infected with 5×10⁵ yeast cells were evaluated at 7 and 14 days post-<i>H. capsulatum</i> infection. The data are expressed as the mean ± SEM from one representative experiment of a total of three experiments (n = 6/each experiment). *sv129 compared with C57BL/6. p<0.05 was considered significant.</p

Differential 5-LO enzyme expression and LTB₄ production in C57BL/6 and 129/Sv mice.

<p>The expression of <i>alox5</i>, <i>aloxp5</i> and <i>Ltbr1</i> mRNA in PMs from C57BL/6 and sv129 (A) and PMs infected with <i>H. capsulatum</i> (B) for 6 h as described in the Material and Methods. (B) LTB₄ production by PMs from C57BL/6 and 129/Sv after <i>in vitro</i> infection with <i>H. capsulatum</i> (MOI = 1∶5) was measured by ELISA. The data are expressed as the mean ± SEM from one representative experiment of a total of two experiments (n = 3 to 5/each experiment). *sv129 compared with C57BL/6. p<0.05 was considered significant.</p

Effect of endogenous and exogenous LTB₄ on the phagocytosis of <i>H. capsulatum</i> by C57BL/6 and 129/Sv macrophages.

<p>PMs from C57BL/6 and 129/Sv mice were incubated for 2 h with IgG-opsonized or non-opsonized yeast cells at a yeast-to-cell ratio of 1∶5. (A) PMs were pretreated with the LT synthesis inhibitor MK886 (1 µM) for 20 min. (B) AMs from C57BL/6 and 129/Sv mice were incubated for 2 h with IgG-opsonized or non-opsonized yeast cells at a yeast-to-cell ratio of 1∶5. (C) PMs were pretreated with the LT synthesis inhibitor MK886 (1 µM) for 20 min, followed by challenge with LTB₄ (10 nm) for 5 min before the infection (C). The data are expressed as the mean ± SEM from one representative experiment of a total of two experiments (n = 3 to 5). *sv129 compared with C57BL/6. ^#sv129 and C57BL/6 compared with MK886/LTB₄ treatment. p<0.05 was considered significant.</p

TNF-α production in lung of resistant (129/Sv) and susceptible (C57BL/6) mice.

<p>Lungs were removed at 7 and 14 days after i.t. injection of PBS or 5×10⁵<i>H. capsulatum</i> yeast cells. TNF-α levels were determinate by ELISA. Data are presented as the mean ± SEM and are representative from one of two independent experiments (n = 6/each experiment). * 129/Sv compared with C57BL/6; ^#129/Sv <i>H. capsulatum</i> compared with C57BL/6 <i>H. capsulatum</i>. p<0.05 vs. PBS.</p