GFP mRNA and protein suppression in THP-1 cells.

<p>(<b>A</b>) Decrease in GFP mRNA levels, and (<b>B</b>) decrease in GFP protein levels (i: based on mean GFP fluorescence and ii: based on GFP-positive cell population). The GFP-positive THP-1 cells were treated with 50 nM GFP siRNA (or control siRNA) delivered with PEI25, PEI2-LA (2.1 LA/PEI) and PEI2-CA (6.9 CA/PEI; 4∶1 = polymer:siRNA ratio) for 1 to 3 days, after which the cells were harvested for PCR (<b>A</b>) and flow cytometry (<b>B</b>).