STAT3 silencing potentiate Ara-LAM mediated abrogation of SOCS3 expression in <i>Leishmania-donovani</i> infected macrophages.

<p><i>Peritoneal macrophages (2×10⁶ cells/mL) were transfected with control siRNA or STAT3-specific siRNA, subsequently followed by Ara-LAM treatment (for 3 hr) and Leishmania infection for 24 hr. The cells were then lysed and subjected to Western blot with anti-SOCS3 antibody as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0024141#s4" target="_blank">Materials and Methods</a> (A). In a separate experiment macrophages were transfected with either control-siRNA or</i> STAT3 <i>specific siRNA, subsequently followed by Ara-LAM treatment for 3 hr and Leishmania infection for another 3 h. RNA was isolated and semi quantitative RT-PCR analyses for SOCS3 and GAPDH were done. Data represented here are from one of three independent experiments, all of which yielded similar results (B). Changes in expression of SOCS3 mRNA were also determined by quantitative real-time PCR. Results are presented as changes (n-fold) relative to uninfected control cells. The experiment was repeated 3 times, yielding similar results (C). *P<.001 compared with infected macrophages. The comparison of SOCS3 expression between Ara-LAM treated infected macrophages and STAT3 siRNA group did not show any statistical significance.</i>