What is QTube?

QTube is an automated fingerprint-based method to quantitatively assess the consistency of gating data across a panel of tubes. QTube produces a numerical as well as a graphical assessment of gate data consistency. The algorithm operates directly on list-mode FCS data and requires no operator intervention.


How QTube came to be
QTube is a very simple application of Cira's Cytometric Fingerprinting. We actually invented this application in the course of using CF to predict cytogenetic abnormality using Flow data alone for one of our clients (which, by the way, was successful). In the course of this project we found that some of the FCS data were not internally consistent. We wanted to exclude these data for purposes of building a predictive fingerprint-based classifier. Being lazy and not wanting to manually examine over 8,000 dotplots individually, we thought up this scheme to let the computer do it for us (albeit in a database-driven high-throughput environment). It saved us lots of time.


In a nutshell, QTube looks at the similarity of event distributions in two or more tubes. Without you needing to direct its attention (via gating for example), QTube computes a fingerprint for each tube, and then compares each fingerprint against the aggregate. It provides feedback as to how similar the distributions are, which ones (if any) are outliers, and by how much. It does all of this with a single click. If you like, you can easily export the result to Excel or other analysis or reporting software.

How does it work?

QTube looks at a subset of parameters that are common across a panel of tubes. These parameters may be those you use for describing gates for multiple subsets that are used to gate each tube in a panel. For example, CD45 and Side Scatter are commonly used to gate subsets in immunophenotyping in Leukemia or Lymphoma panels. Parameters that differ across the panel (e.g. different antibodies conjugated to FITC in different tubes) are simply ignored.

QTube is a simple-to-use Java application that's powered by a complex underlying technology, Cytometric Fingerprinting, a new computational approach to the analysis of Flow data developed by Cira Discovery Sciences, Inc. in response to a need to extract more information from large numbers of multicolor FCS files in a High Throughput workflow. In order to use QTube you needn't worry about the math behind it, though if you're interested we refer you to the section onTheory of Operation.

How much does it cost?

QTube is free! Once you have it you are free to use it as you like. You may keep your version up to date, also for free, by visiting our website from time to time. If you'd like us to add functionality that may be broadly useful, feel free to ask (we'll do our best to honor your request). If you need customization of QTube or a more elaborate application of Cytometric Fingerprinting specifically for your environment, we'll be happy to discuss that with you. We hope you find it useful and if so, feel free to let us know about that, too!

What strings are attached?

Only one. If you use QTube to report QC results outside of your organization (for example, in a report you send to a referring physician or paying client), you must leave the QTube attribution (that's part of the Export result and at the bottom of the main QTube screen) intact. That's the only string, period!