Characterisation of THP-1 macrophage phenotype and LPS responses.

<p>THP-1 monocytes (THP-1) cells were stimulated to differentiate in the presence of dihydroxyvitamin D3 (VD3), phorbol ester (PMA) or both (VD3/PMA) for 72 hours prior to analyses. (A) Flow cytometric analysis of cell surface CD14 expression using indirect immunofluorescence with mAb 63D3 detected with anti-mouse-phycoerythrin. Frequency histograms of at least 5000 events are shown for each cell type (open black: CD14; solid grey: IgG1/κ isotype control). Data shown are representative of at least three independent experiments. (B) Production of TNF-α in response to a range of LPS concentrations for 4h in the presence of 10% v/v normal human serum, detected by ELISA (data shown are mean ± SE for 3 independent experiments). (C) Flow cytometric analysis of cell surface TLR-4 using direct immunofluorescence with mAb HTA-125-phycoerythrin (open black: anti-TLR-4; solid grey: IgG2a/κ isotype control). Data shown are representative of at least three independent experiments.