Figure 1: The effect of HSO (a), AHK (b), EHK (c), AHH (d), and EHH (e) on PBMC proliferation. PBMCs were separated using Ficoll-Paque density centrifugation, seeded in 96-well plates and treated with 10 μg/ml LPS and extracts at the indicated concentrations. The cells were then incubated for 24 h before the addition of WST-1 cell proliferation assay reagent.