Quantifying subcellular dynamics in apoptotic cells with two-dimensional Gabor filters

Abstract

We demonstrate an optical Fourier filtering method which can be used to characterize subcellular morphology during dynamic cellular function. In this paper, our Fourier filters were based on two-dimensional Gabor elementary functions, which can be tuned to sense directly object size and orientation. We utilize this method to quantify changes in mitochondrial and nuclear structure during the first three hours of apoptosis. We find that the technique is sensitive to a decrease in particle orientation consistent with apoptosis-induced mitochondrial fragmentation. The scattering signal changes were less pronounced in the nucleus and the remainder of the cytoplasm. Particles in these regions were less oriented than mitochondria and did not change orientation significantly.

Introduction: Feature Issue on Optical Imaging and Spectroscopy

“…Leaving the realm of tissue imaging, two final studies address issues related to imaging of sub-cellular structures and function. Antkowiak et al [ 22 ] study the quantitative phase of the dynamic cellular response in femtosecond laser photoporation and Pasternack et al [ 23 ] elucidate the effects of two-dimensional Gabor filters on the quantification of sub-cellular dynamics in apoptotic cells.…”