Automation of Fluorescent Dot Counting in Cell Nuclei

*Faculty of Applied Physics, Delft University of Technology, The Netherlands. ^Laboratory for Cytochemistry and Cytometry, University of Leiden, The Netherlands

Two chromosome probes + nucleus counterstain

We have developed a completely automated fluorescence microscope system that can examine 500 cells in approximately 20 minutes to determine the number of labeled chromosomes (seen as dots) in each cell nucleus. This system works with two fluorescent dyes Ð one for the DNA hybridization dots (e.g. FITC) and one for the cell nucleus (e.g. DAPI). After the stage has moved to a new field the image is automatically focused, acquired by a Photometrics KAF 1400 camera, and then analyzed on a Macintosh Quadra 840AV computer. After the required number of cells has been analyzed, the user may interact to correct the computer by working with a gallery of the cell images. The machine accuracies are equal to panels of human experts (manual) and limited (ultimately) by the overlapping of dots in the 3D cell as seen through the 2D projection.

e-mail: young@ph.tn.tudelft.nl