Label-Free Multi Parameter Optical Interrogation of Endothelial Activation in Single Cells using a Lab on a Disc Platform

Sci Rep. 2019 Mar 11;9(1):4157. doi: 10.1038/s41598-019-40612-8.

Abstract

Cellular activation and inflammation leading to endothelial dysfunction is associated with cardiovascular disease (CVD). We investigated whether a single cell label-free multi parameter optical interrogation system can detect endothelial cell and endothelial progenitor cell (EPC) activation in vitro and ex vivo, respectively. Cultured human endothelial cells were exposed to increasing concentrations of tumour necrosis factor alpha (TNF-α) or lipopolysaccharide (LPS) before endothelial activation was validated using fluorescence-activated cell sorting (FACS) analysis of inflammatory marker expression (PECAM-1, E-selectin and ICAM-1). A centrifugal microfluidic system and V-cup array was used to capture individual cells before optical measurement of light scattering, immunocytofluorescence, auto-fluorescence (AF) and cell morphology was determined. In vitro, TNF-α promoted specific changes to the refractive index and cell morphology of individual cells concomitant with enhanced photon activity of fluorescently labelled inflammatory markers and increased auto-fluorescence (AF) intensity at three different wavelengths, an effect blocked by inhibition of downstream signalling with Iκβ. Ex vivo, there was a significant increase in EPC number and AF intensity of individual EPCs from CVD patients concomitant with enhanced PECAM-1 expression when compared to normal controls. This novel label-free 'lab on a disc' (LoaD) platform can successfully detect endothelial activation in response to inflammatory stimuli in vitro and ex vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Shape
  • E-Selectin / genetics
  • E-Selectin / metabolism
  • Flow Cytometry / instrumentation
  • Flow Cytometry / methods*
  • Human Umbilical Vein Endothelial Cells / cytology*
  • Human Umbilical Vein Endothelial Cells / drug effects
  • Human Umbilical Vein Endothelial Cells / metabolism
  • Humans
  • Intercellular Adhesion Molecule-1 / genetics
  • Intercellular Adhesion Molecule-1 / metabolism
  • Lipopolysaccharides / pharmacology
  • Platelet Endothelial Cell Adhesion Molecule-1 / genetics
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism
  • Tumor Necrosis Factor-alpha / pharmacology

Substances

  • E-Selectin
  • Lipopolysaccharides
  • Platelet Endothelial Cell Adhesion Molecule-1
  • Tumor Necrosis Factor-alpha
  • Intercellular Adhesion Molecule-1