Quantitative Analysis of Caspase-1 Activity in Living Cells Through Dynamic Equilibrium of Chlorophyll-Based Nano-assembly Modulated Photoacoustic Signals

ACS Appl Mater Interfaces. 2016 Jul 20;8(28):17936-43. doi: 10.1021/acsami.6b05795. Epub 2016 Jul 5.

Abstract

In situ construction of self-assemblies with unique property in living systems is a promising direction in the biomedical field. The noninvasive methods for significant enzyme activity in living cells or living subjects are imperative and meantime challenge tasks. The dynamic process of self-assembly of chlorophyll-based molecules in complex biological systems can be monitored by photoacoustic signals, which supports a noninvasive way to understand and quantitatively measure the activity of caspase-1. Furthermore, the activity of caspase-1 enables reflection of the bacterial infection in the early stage. Here, we present a biocompatible self-assembly from chlorophyll-peptide derivatives and first correlate the dynamic equilibrium with ratiometric photoacoustic signals. The intracellular equilibrium was managed by a bacterial infection precaution protein, i.e., caspase-1. This system offers a trial of noninvasive method to quantitative detection and real-time monitoring of bacterial infection in the early stage.

Keywords: bacterial infection; caspase-1; chlorophyll; dynamic equilibrium; self-assembly.

MeSH terms

  • Animals
  • Caspase 1 / analysis
  • Caspase 1 / metabolism*
  • Chlorophyll / chemistry*
  • Macrophages / enzymology*
  • Mice
  • Nanostructures / chemistry*
  • Photoacoustic Techniques / methods*
  • RAW 264.7 Cells
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Staphylococcal Infections / enzymology
  • Staphylococcus aureus

Substances

  • Chlorophyll
  • Casp1 protein, mouse
  • Caspase 1