Wavelength-dependent backscattering measurements for quantitative real-time detection of apoptosis in living cells

摘要

Our goal is to demonstrate the use of in vitro elastic scattering spectroscopy (ESS) to monitor changes in light-scattering properties of cells due to apoptotic micro-morphology changes. We developed an instrument capable of wavelength-resolved ESS measurements from cell cultures in the backward direction along with an algorithm to extract the size distribution of scatterers in the sample using Mie theory. CHO cells were cultured to confluence on plates and were rendered apoptotic with 2μM staurosporine. Backscattering measurements were performed on pairs of treated and control samples at times up to 6 hours post treatment. Initial results indicate that ESS is capable of discriminating between treated and control samples as early as 15 minutes post treatment. Extracted size distributions from treated and control samples show an increase in the number of small particles with a corresponding decrease in larger particles after treatment. This is consistent with expected morphological changes during apoptosis, and work continues to correlate these size distributions with underlying morphology.