38
- Follow the manufacturer’s instructions for the proper sealing
of the Gene Frame on the slide. Do not remove the upper
plastic cover at this step. - This step should be done quickly. The best is to hold the cov-
erslip in one hand while pipetting the agarose with the other
hand. This allows putting the coverslip rapidly on the warm
agarose, preventing it from solidifying and making the agarose
pad very flat. This will assure the unique microscope focus
across the entire microscope field. Therefore, all imaged cells
will be exploitable for analysis. - Try avoiding the air bubbles while pipetting the agarose as the
air bubbles have high autofluorescence. - Make sure that the agarose pad dries enough after plating the
cells on it and before putting the coverslip. White traces of the
liquid become visible on the agarose pad that is ready for
imaging. Otherwise, if the agarose pad is not dry enough, the
cells will not attach to it, they will swim, and the imaging will
be impossible. - Make sure that the agarose pad does not dry too much and
become wrinkled. This will prevent the proper sealing of the
coverslip to the agarose pad and degrade the image quality. - Avoid the fields with cells in double layer and also fields where
too many cells are sticking to each other. In such cases the foci
detection will be difficult.
Acknowledgments
This work was supported by the ANR young researcher grant
ANR-14-CE09-0015-01 to M.E., and by Idex ANR-11-
IDEX-0005-01 / ANR-11-LABX-0071 and AXA Research grants
to I. M.References
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