(194ae) Macrophage Polarization on Microporous Scaffolds and ECM Secretion of Fibroblasts

Monocyte-derived macrophages are known to play major roles in orchestrating the biomaterial-tissue interactions. Clinical success of various medical implants and tissue engineering scaffolds highly is highly dependent on the nature of those interactions. In this research, using the polydimethylsiloxane (PDMS)-based microporous scaffolds, we performed systematic studies on the macrophage polarization on polymeric microporous scaffolds as a function of pore size (50-100 µm, 100-150 µm, 150-300 µm, 300-500 µm) and surface chemistries (no modification, polydopamine (PDA) coating, PDA coating + cell adhesive ligand (RGD)). The microporous structure of the scaffolds was characterized by scanning electron microscope (SEM), and the surface chemistry by X-ray photoelectron spectroscopy (XPS). Microbead-based multiplex assay was used to measure various proinflammatory and anti-inflammatory cytokines released by macrophages. In order to assess the effects of macrophage polarization on other tissue resident cells, dermal fibroblasts were cultured in the presence and absence of macrophages. Their proliferation and extracellular matrix (ECM) secretion were quantified. The results from this systematic study will provide valuable design principles for medical implants and tissue engineering scaffolds.