Flow Cytometry in the Clinic

Flow cytometry is a technique used to count and analyze the size, shape and properties of individual cells. Cells labeled with fluorescent markers are passed in a rapid stream past the instrument’s laser at rates upwards of 10,000 cells per second. Emitted fluorescent parameters are detected and analyzed, allowing biologists to obtain specific information about individual cells.

Watch this video to learn how flow cytometry works

Not just a valuable research tool, flow cytometry is also finding its stride in several clinical areas.

Following BD Biosciences’ launch of a new sample preparation instrument, we spoke to Stephen Gunstream, VP and general manager, to get his insights on the role of flow cytometry in diagnostics and clinical trials in 2019.

Michele Wilson (MW): How have flow cytometry systems changed over the years, in terms of both throughput and the information that can be generated? 

Stephen Gunstream (SG): The earliest flow cytometers were large, very complex instruments run by highly-skilled operators.  These instruments, although an improvement over traditional microscopy, were only capable of measuring a small number of basic characteristics associated with each cell.

Technology advances have allowed the development of flow cytometers with a wide spectrum of capabilities – from easy-to-use instruments dedicated to specific application areas to high-end research systems capable of detecting up to 50 fluorescence parameters per cell.

MW: Which aspects of biologics discovery have benefited the most from advances in flow cytometry?

SG: Flow cytometry has historically had two primary clinical uses:

• counting CD4 T cells in patients with HIV as an indication of immune status
• the diagnosis/monitoring of blood cell cancers. 

Emerging clinical application areas are focused on the functions of specific types of immune cells, including in the context of immunotherapy and autoimmune disease.

MW: How extensively is flow cytometry used as a diagnostic tool in the clinic? 

SG: We expect Clinical Flow Cytometry to be approximately a billion-dollar market, and currently flow cytometry is used for the diagnosis of almost all lymphoma and leukemia disease globally.

MW: How does the BD FACTSDuet system improve on existing flow cytometry platforms? 

SG: FACSDuet is physically integrated with BD FACSLyric™ clinical flow cytometer allowing technicians to load samples and reagents onto the BD FACSDuet™ system and receive data once the samples are fully processed from the BD FACSLyric™ clinical flow cytometer.

The new fully automated sample preparation instrument enables clinical laboratories to improve their efficiency by reducing errors and limiting the manual user interactions required to run assays on the BD FACSLyric™ clinical flow cytometer.

MW: What is “gating” in flow cytometry? 

SG: Flow cytometry is powerful in that it can analyze large numbers of cells one cell at a time. 

Gating is the method used to identify specific populations of cells within the overall sample. 

This is used for almost all flow cytometry and is particularly useful in looking for specific cells within the immune system.

MW: How extensively is flow cytometry used to monitor parameters in clinical trials?  

SG: In immuno-oncology clinical trials, flow cytometry is currently used to monitor patients’ immune response in about 20% of the new therapies that are being developed.

What does it mean for you to have obtained CE-IVD certification? 

SG: To obtain CE IVD certification means that BD has self-certified FACSDuet under the EU IVD Directive and therefore BD can apply the CE mark and label the product as an IVD for commercialization in the EU.

Stephen Gunstream was speaking to Michele Wilson, Science Writer for Technology Networks