Transcriptional profiling of human monocyte-derived macrophages

In this study we compared the response of human monocyte-derived macrophages differentiated with either granulocyte-macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF) to the most common activation stimuli: LPS plus interferon-γ to induce macrophage polarization towards the M1 type or IL-4 to induce macrophage polarization towards the M2a type. Additionally, IL-10 was used to drive M-CSF-primed macrophages into the M2c state. We used the the whole-human genome microarray to determine genes that were up- or downregulated by the activation stimuli in both macrophage lineages, with focus on genes implicated in immune response. We generated 7 different macrophage subtypes in three biological replicates: Isolated monocytes of three healthy donors (biological replicates) were differentiated with either 25ng/ml GM-CSF or 50ng/ml M-CSF for 7d. GM-CSF-differentiated macrophages were then either mock-activated with culture medium only (control; condition 1) or activated with 100 ng/ml LPS + 25ng/ml IFNγ (condition 2), or 20 ng/ml IL-4 (condition 3) for 2d (48 h). This activation regime was also used to activate M-CSF-differentiated macrophages, which were in additionally activated with 20 ng/ml IL-10 (condition 4) for 2d (48 h).