Human CD14 positive monocytes were purified from healthy volunteers’ blood and cultured in vitro for 4, 12, 24, 72 hours. While culturing, macrophages were activated alternatively with interleukin-4 (IL-4 100 ng/ml) or classically with interferon-gamma (IFNg 100 ng/ml)+tumor necrosis factor (TNF 50 ng/ml) or left without activation. Simultaneously, macrophages were also treated with vehicle (DMSO:ethanol) or 1mM synthetic PPARg agonist, Rosiglitazone. We used Affymetrix microarrays (U133Plus 2.0) to analyze activation and PPARg-induced gene expression changes.