Fig. 3: Intracellular imaging of subcellular structures.

a Fluorescence images of the microfilaments (F-actin filaments) of a living adipose cell. The weak fluorescent signals (a1) were efficiently enhanced by the lipid droplet (diameter: 7.7 μm) (a2). b Normalized intensity distribution along the observation lines through microfilaments without (blue dashed in a1) and with (red dashed in a2) the lipid droplet. c Fluorescence images of the microfilaments in a living adipose cell with a 12.5-μm lipid droplet. d Fluorescence images of the microfilaments in a fixed adipose cell with an 18.6-μm lipid droplet. e Fluorescence and bright-field images of the lysosomes in a living adipose cell with an 11.3-μm lipid droplet. f Fluorescence and bright-field images of the adenoviruses in a living adipose cell with an 8.1-μm lipid droplet, the blue lines represent the movement trajectory of the adenoviruses in 10 min. The fluorescence images were focused on the surfaces of the cells (c1, d1, e1, and f1) and the virtual image planes (c2, d2, e2, and f2) formed by the lipid droplets. The bright-field image was focused on the virtual image plane formed by the lipid droplet (e3, f3). g The microfilament movement monitored by the lipid droplet (diameter: 10.0 μm) inside the cell in 10 min