Cell Cycle Analysis
Live FUCCI mESC imaged for over 48 hours with the 3D Cell Explorer-fluo
Cell cycle and cell death are basic cellular processes. Modifications in cell shape, cell volume and cell organelles are observed in each of the phases of the cell cycle and even during cell death.
Nanolive imaging allows for non-invasive long-term live cell imaging at very high spatio-temporal resolution. This breakthrough leads to the observation and characterization of continuous processes such as pre-mitotic nuclear rotation, mitosis, apoptosis, necrosis, autophagy, and pyroptosis in a new, holistic fashion.
Researchers from EPFL demonstrated and published on PLOS Biology that mammalian cellular organelles such as lipid droplets (LDs) and mitochondria show specific RI 3D patterns. Moreover, they could observe the shape and dry mass dynamics of LDs, endocytic structures, and entire cells’ division that have so far, to the best of our knowledge, been out of reach. Finally, they could capture the motion of many organelles at the same time to report a multiorganelle spinning phenomenon and study its dynamic properties.
Cell division analysis
Kinetics, dynamics and morphological changes unveiled during mitosis
The 3D Cell Explorer is able to discriminate different mitotic phases based on chromatin RI values and monitor changes in nuclear RI, shape and size during mitosis (e.g. DNA condensation, chromosomes alignment and segregation, mitotic spindle formation, metaphase plate, sister chromatids, contractile ring).
Furthermore, it is possible to follow changes in cellular shape and thickness during cell division and measure the processes of surface attachment/detachment.
The video demonstrates a cell division taking place in a living sample of human mesenchymal stem cells cultured with low-serum cell growth medium and observed under the 3D Cell Explorer.
Pre-mitotic nuclear rotation
Label-free live cell imaging of mouse breast cancer cells
Nanolive imaging with the 3D Cell Explorer allows for the visualization of the interactions of cellular organelles, by their refractive indices. This led to the observation of nuclear rotation implicated in cellular reorganization before mitosis.
The video shows mouse breast cancer cells imaged with the 3D Cell Explorer: Nanolive imaging reveals 3D (in all axes) nuclear and organelle rotations in mammalian cells.
With special thanks to NBE therapeutics for the reagents used to obtain the video.
 P. A. Sandoz et al., “Label free 3D analysis of organelles in living cells by refractive index shows pre-mitotic organelle spinning in mammalian stem cells,” bioRxiv, p. 407239, Sep. 2018.
This video shows long-term live cell imaging (12h) of multinucleated mouse pre-Adipocyte trying to undergo mitosis. Due to the excess of genetic material the cell fails to replicate and dies by apoptosis.
In this video, Cell death was induced by the addition of a drug (combination of imipramine and ticlopidine) to mouse glioblastoma cells (LN18). The cells were imaged every 60 seconds over a period of 9 hours. You can see the vacuolization of the cytoplasm followed by heavy lysosomal activity within these autophagic cells. The large autophagosomes fuse with lysosomes, which degrade the organelles and proteins from the cell’s cytoplasm.
Special thanks to the Laboratory of Translational Oncology – Prof. Douglas Hanahan from EPFL.
This is a very rapid process characterized by swelling of organelles, dilatation of the nuclear membrane, increased cell volume (oncosis), culminating in the disruption of the plasma membrane and subsequent loss of intracellular contents. This video shows ID8-ova cells (ID8 murine ovarian tumor cell line transduced with ovalbumin). NaOh was added to the medium during the acquisition to trigger this type of cell death. The cells were imaged for 2 minutes at a frequency of 1 image every 2 seconds.
In this video mouse macrophages were infected with Listeria. The immune cells recognize the foreign danger signals within themselves, release pro-inflammatory cytokines, swell, burst and die. These cells were imaged for 25 minutes at a frequency of 1 image every 15 seconds.
Mouse Fibroblastic Reticular Cell (FRC) mitosis
Programmed Cell Death of a mouse Preadipocyte cell