Proteomic profiling of macrophages: effects of inflammatory activation and anti-inflammatory treatment with IBD therapeutics

Inflammatory bowel diseases (IBD) are chronic disorders characterized by persistent immune dysregulation in the intestinal mucosa, with macrophages playing a central role in disease pathogenesis. In this study, primary human monocyte-derived macrophages (MDMs) were stimulated with lipopolysaccharide (LPS) to model innate immune activation, and subsequent proteomic changes were analyzed by mass spectrometry. The effects of three established IBD drugs, mesalazine, prednisolone and 6-mercaptopurine (6-MP), were systematically evaluated within this model. LPS stimulation resulted in activation of proteins related to pro-inflammatory pathways, including NF-κB signaling, which was reflected by increased expression of cytokine- and adhesion-related proteins such as IL1B, IL8 and ICAM1. Mesalazine treatment induced a moderate modulation of inflammatory regulators, prednisolone produced a strong suppression of pro-inflammatory and complement proteins, and 6-MP caused broad alterations in ribosomal, metabolic and apoptosis-associated proteins. These results indicate that the LPS-stimulated MDM model can reproduce essential features of macrophage activation in IBD and differentiate drug-specific proteomic signatures that are consistent with known mechanisms of action.