Abstract

We present a label-free imaging method for studying lipid droplets (LDs). LDs are lipid storage organelles in most eukaryotic cells. Recently, many studies have reported that LDs are related pathologic conditions including obesity, viral infection, and inflammatory diseases. Fluorescent proteins have been widely used to image LDs, but photobleaching and photodamage are limiting factors in live-cell imaging. Three-dimensional (3-D) refractive index (RI) tomograms were reconstructed from multiple holographic images with various illumination angles. We calculate mass and size of LDs from reconstruct 3-D RI tomograms. Time-lapse imaging provides 3-D dynamics of LDs. We propose that quantitative phase imaging techniques can be an invaluable tool for investigating pathophysiology of LDs

© 2014 Optical Society of America