Transcriptomic profiling of the development of the inflammatory response in human monocytes in vitro

To investigate the time-dependent and coordinated sequence of inflammation-related events, and the dynamic features of macrophage polarisation/activation, we build and validated an in vitro model based on primary human monocytes Monocytes were sequentially exposed to relevant stimuli: hrCCL2 (10 ng/ml; 0-2 h), LPS (5 ng/ml; 2-14 h) hrTNF-α (10 ng/ml; 3-14 h), hrIFN-γ (25 ng/ml; 7-14 h), hrIL-10 (20 ng/ml; 14-24 h), hrTGF-β (10 ng/ml; 24-48 h). The temperature was raised to 39 °C from 2 h to 14 h. Fresh monocytes were taken as time 0. Samples were collected at different time points and processed for total RNA extraction and hybridization on Affymetrix microarrays. Nine donors (A, B, C, D, E, F, G, H, L) were used for each of the 5 conditions (0, 4, 14, 24, 48 h) for a total of 45 samples, and 3 donors (M, N, O) were used for the following time-points: 0, 2, 2,5, 3, 3,5 h.