Industry executives “go with the flow” – flow-cytometry trends, that is

Almost 60 years ago — in 1953 — the first impedance-based flow-cytometry device was patented. MLO asked industry experts to tell us exactly how far flow-cytometry technology has come since then, and what clinical laboratories can expect as far as trends in flow-cytometry products, testing techniques, equipment, and services.

More colors, more information

“Clinical flow cytometry, in which individual cells in a fluid suspension are evaluated to diagnose and/or monitor disease states, is progressing rapidly. Current state-of-the art flow cytometers can analyze eight to 10 different fluorescent dyes, or fluorochromes, simultaneously. Since each fluorochrome is linked to a specific antibody, these instruments evaluate eight to 10 unique proteins on an individual cell, providing exponentially more information than older three- to six-color methodologies. Among the new methods, 10-color flow cytometry is particularly powerful, providing approximately 60% more information than eight-color flow cytometry when unique pairwise combinations of cellular proteins are regarded as the basic unit of information. This increased information is particularly advantageous in evaluating small specimens with limited material, and in searching for minimal residual disease after therapy. Markedly expanded availability of appropriate fluorochrome-conjugated antibodies, plus the development of sophisticated manufacturer and third-party software for data analysis, has made eight- to 10-color flow cytometry attainable to any laboratory willing to devote the time and effort to validate these assays.”

—Steven J. Kussick, Director of Hematopathology and Flow Cytometry
PhenoPath Laboratories, Offers 9- and 10-color clinical flow cytometry,

Modern hematology analyzers embrace
basic flow-cytometry techniques

“It is a well-known fact that traditional flow cytometry is considered the best method for the differentiation of cell populations. It is also well known that traditional flow cytometry requires the use of costly antigen-antibody reagents, and that the procedures can be cumbersome and time consuming. In the past 10 years, this has not gone unnoticed by manufacturers of routine hematology analyzers. Some modern hematology analyzers have embraced the basic techniques of flow cytometry, using highly-specific polymethine dyes to adapt that sophisticated technology to the high volume and automation requirements of the clinical lab. In order to meet the clinical demands for more accurate routine differentiation of normal and abnormal cells, flow applications using simple but sophisticated fluorescent dyes will continue to be expanded to fit the needs of routine complete blood-count testing.”

—Barbara Connell, MS, MT(ASCP)SH, Senior Manager, Scientific Marketing
Sysmex America, Maker of XE-5000 automated hematology analyzer,

Testing for PNH spurred by demand

“A recent development in flow cytometry has been increased testing for paroxysmal nocturnal hemoglobinuria (PNH). The use of flow cytometry in PNH diagnosis is not particularly new; it has been preferred to the classic Ham test for a number of years. More recent clinical developments, however — such as the introduction of a PNH-specific treatment (Eculizumab) and the increased recognition of PNH clones in aplastic anemia and myelodysplastic syndromes — have spurred testing demand. In addition, the glycosylphosphatidylinositol- or GPI-, deficient PNH clones in aplastic anemia and myelodysplastic syndrome may be small, requiring the development of clinical ‘high-sensitivity’ PNH assays. High-sensitivity PNH assays make use of flow cytometry to analyze many thousands of cells in a relatively short period of time. Multiple antigens are examined simultaneously. In particular, a mutated bacterial toxin, known as FLAER, is used to assess leukocyte expression of GPI-linked proteins. High-sensitivity assays that incorporate FLAER are able to detect PNH clones of 0.1% or smaller.”

—Steven S. Goldstein, Hematopathologist
NeoGenomics Laboratories, Maker of high-sensitivity PNH assay,

Diagnostically limited samples benefit with
eight-color immunophenotyping

“Current advances in flow-cytometric analysis have focused on the use of novel antibody configurations and eight-color multiparameter immunophenotyping. The recent consensus guidelines on diagnosing PNH by flow cytometry point to the expanded benefits of new antibody configurations. Using a FLAER-based assay to analyze leukocytes for PNH can provide both diagnostic and prognostic data for multiple hematopoietic disorders. Additionally, as a national laboratory, approximately 10% of our daily samples are diagnostically limited. This represents a significant volume of work where the advantages of eight-color immunophenotyping provide increased clinical benefit.”

—Lawrence Hertzberg, MD, Medical Director
CSI Laboratories, Offers diagnostic testing services,

Flexible data-management for
diagnostic genetics lab

“Clinical diagnostics and the LIS are getting more complex. Genetics testing has moved into the mainstream; however, most genetics LIS vendors are still behind the industry curve. Integration with institutions’ core systems, including the LIS, will be a continued challenge. A technique for counting, examining, and sorting microscopic particles suspended in a stream of fluid, flow cytometry is a unique form of genetic research that utilizes concentrated light to determine the size, number, sort, and other relevant data pertaining to particulate matter suspended in fluid media. Information systems can optimize flow-cytometry workflow in the laboratory and allow for further refinement of chromosomal-derived data in molecular genetics. A superior management application that allows for optimized workflows in flow-cytometry research — resulting in minimal data loss and reliable data capture — can allow for further refinement of chromosomal-derived data in molecular genetics. Using a well-designed information solution, both clinicians and laboratory scientists can effectively analyze information derived from this research technique and achieve better design reconfigurations in experimental workflows, task management, and other activities for guiding research in the right direction.”

—Gilbert Hakim, Founder and CEO
SCC Soft Computer, Maker of SoftFlowCytometry,