Electrochemistry-based assay for monitoring of adherent macrophages and foam cells on Ab-CD36 modified electrospun nanofibers

Abstract

Atherosclerosis, a major cause of heart attacks, is a chronic inflammatory disease marked by the accumulation of lipid-laden foam cells and immune cells in the arterial wall. Here, for the first time, the adhesions of macrophages and foam cells toward the developed polystyrene/graphene oxide-3-aminopropyltriethoxysilane/Anti-CD36 (PS@GAPTES@Ab-CD36) electrospun nanofiber (ESNF)-based biofunctional surface was investigated using electrochemical measurements and fluorescence imaging. After the oxidative modification of high-density lipoprotein (HDL) was carried out, macrophage cells were incubated with different concentrations of oxidative HDL (ox-HDL) to determine the most suitable concentration of ox-HDL for obtaining foam cells. Afterward, electrochemical measurements were carried out using PS@GAPTES@Ab-CD36 modified screen-printed carbon electrode (SPCE) in the presence of foam cells and macrophages. The linear range of both cell types was 10-103 cells mL-1. The limit of detection (LOD) was calculated as 15 and 17 cells mL-1 for the foam cells and macrophages, respectively. It was observed that foam cells' adhesion to the PS@GAPTES@Ab-CD36 biofunctional surface was relatively high compared to macrophage cells because of the enhanced CD36 expression on the surface of foam cells. Finally, macrophage and foam cells were seeded on PS@GAPTES@Ab-CD36 and PS@GAPTES (control) ESNFs, and DAPI staining was carried out for fluorescence imaging.