Nucleosides modulate <i>in vivo</i> expression of suppressive genes and mediate immunoregulatory effects by IL-10 during <i>Leishmania amazonensis</i> infection.

<p>Expression levels of IDO (<i>A</i>), arginase-1 (<i>B</i>), COX₂ (<i>C</i>), or IL-10 (<i>D</i>) mRNA into ears from C57BL/6 mice that were infected or not (naïve) with 10⁶<i>L</i>. <i>amazonensis</i> promastigotes in the presence of ADO+AMP or PBS at 11 weeks post infection. <i>E</i>, IL-10 production in cultured draining lymph node cells from ADO+AMP or PBS-treated mice was determined by ELISA. Data are shown as the means ± SEM of two separate experiments; each experiment was performed with four (naïve) or six (infected) mice per group (<i>n</i> = 4–6). *, <i>p</i><0.05 relative to naïve mice; ^#, <i>p</i><0.05 compared with the PBS-treated group. Ear lesion (<i>F</i>, <i>G</i>) and parasite burden (<i>H</i>)—by a limiting-dilution assay—in WT and IL-10^-/-mice at 11 weeks p.i. were determined. Data are shown as the means ± SEM of two separate experiments; each experiment was performed with five mice per group (<i>n</i> = 5). <i>G</i>, representative photographs of ears at 11 weeks post infection.