Often, the name of an FCS data file does not convey all the information you require to differentiate between other FCS files. When opening an FCS data file in FCS Express, you can view the FCS files by the specific FCS header keywords that you want to display, which allows you to easily select the correct FCS data file. The FCS header keywords are stored in the FCS file. For example, you could set up FCS Express to display the "sample ID" and "tube name" (which is used when acquiring data from a FACSDiVa machine), along with the actual FCS filename, for each FCS file within FCS Express. Then, after creating a plot, when you are prompted to select an FCS file to be displayed in that plot, you will see in the Browse window the FCS files displaying the information that you had previously setup. The image in Figure 1 displays the Browse window for opening an FCS file, where FCS Express was setup to display the files by the number of events in the file, the Acquisition machine, and the actual FCS filename.

Figure 1

Setting up the Display for FCS data files

1. Select File --> Edit Preferences.
2. You will then see the screen, shown in Figure 2. From the FCS File selection dialog options section, change the text to display in selection dialog option from Filename only to The text below.



Figure 2

3. In the text box area below The text below option, enter the keyword variables that you want displayed, separated by ",".
   • To display the total number of events in the file, enter <$Sample ID>
   • To display the flow cytometer used to acquire the data, enter <$Tube_Name>
   • To display the FCS filename, enter <$FCSE_FileNameNoPath>
   The final text should read: <$Sample ID>,<$Tube_Name>,<$FCSE_FileNameNoPath>
4. Click OK to save your changes

NOTE: All the available keyword variable names, along with a description of what values they display, can be found when by viewing the FCS file header and clicking on All Keywords….