Fig. 4.

Effect of LDL components on STAT3-phosphorylation in activated CLL cells. A. CLL cells were activated with IL-2 and Resiqimod (labeled “2S”) in the presence and absence of LDLs (0.5 mM) and/or Lalistat (LAL) (1 μM). Densitometric values of p-STAT3 normalized to β-actin expression were determined after 18 h (left panel) (n = 5), cell counts were measured after 4 days by trypan blue exclusion (middle panel) (n = 3), and mean fluorescence intensities of PFO staining to indicate plasma membrane cholesterol levels were measured by flow cytometry after 24 h (right panel) (n = 4). B. 2S-activated CLL cells from 3 different patients were cultured with or without LDL (0.5 mM), oleic acid (OA) (5 μm), linoleic acid (LA) (5 μm), heptanoic acid (HA) (5 μm), propanoic acid (PrA) (5 μm), or octanoic acid (OcA) (5 μm) and normalized phospho-STAT3 levels determined after 18 h. C. 2S-activated CLL cells from 20 different patients were cultured with or without cholesterol (15 μm) and/or methyl-β-cyclodextrin (Cycd) (0.5 mM). Expression of pSTAT3 normalized to β-actin (left panel) was determined for each sample after 18 h and Nile Red-staining measured by flow cytometry to confirm lipid-loading and stripping (right panel). Averages and standard deviations are shown in each graph. *p < 0.05; **p < 0.01; ns, non significant.