Flow Cytometry in Transfusion Medicine: Development, Strategies and Applications

Abstract

Nowadays, flow cytometry represents an essential tool for the daily work in laboratories for transfusion medicine. After cytophotometry of immobilized cells, flow cytometry was developed since the 1960s using moving fluorescence-stained cells. This technique enabled the determination of several thousand cells per second, e.g. from blood, bone marrow, or organ-associated cell suspensions. The introduction of monoclonal fluorescence-labeled antibodies in diagnostics has further accelerated the development of flow cytometry. In the meantime, numerous cellular and nuclear properties can simultaneously be measured on single cell level in automated devices at high speed and precision. Internal standards and quality control systems further increased the accuracy of flow cytometric analyses. Flow cytometry is therefore likewise suitable for routine diagnostics in patients, quality control of blood components and scientific purposes in transfusion medicine. Nevertheless, many flow cytometric applications are related to counting of rare events or detection of cells with low antigen expression. Therefore, several pre-analytic and analytic factors (e.g. erythrocyte lysing procedures, cell gating strategies, etc.) may essentially affect the accurate determination of cell numbers and functions. In this issue, TRANSFUSION MEDICINE AND HEMOTHERAPY starts a recurrent sequence of reviews focused on ‘Flow Cytometry in Transfusion Medicine’. In order to introduce the flow cytometry series, this review summarizes the development, principles, and strategies of flow cytometry as an increasing diagnostic tool in medical laboratories. Also, current and possibly future flow cytometric applications in transfusion medicine are epitomized, e.g. quality control of blood products, immunohematologic diagnostics, hematopoietic progenitor cell transplantation, adoptive immunotherapy, and further therapeutic applications. In following issues of this journal, reviews of notable authors will then focus on special applications and give more detailed insights into single diagnostic fields.

The Impact of Erythrocyte Lysing Procedures on the Recovery of Hematopoietic Progenitor Cells in Flow Cytometric Analysis

“…The success of reconstituting the hematopoietic system after myeloablative therapy and subsequent SCT is closely related to the administration of sufficient and functioning HPCs. Traditionally, these parameters have been evaluated using the colony‐forming test, but these methods are handicapped by a lack of reproducibility and a long assay time [1, 21]. During the past decades, flow cytometry has earned an outstanding role in the enumeration and characterization of HPCs.…”

“…These protocols and guidelines have distinctly improved intra‐ and interlaboratory reproducibility (coefficient of variations), but some critical issues still remain. Most protocols disregard the influence of such sensitive and aggressive protocol steps as cell fixation, centrifugation, and the lysing of erythrocytes, which may have a high impact on cell enumeration [17, 19, 21, 22]. The last sample treatment, in particular, results in a loss of accuracy that has not been investigated in as much detail as has been done for the precision and sensitivity in the determination of CD34 + cells.…”

Automation in Hematology

“…[32], and the immunological classification of leukocytes [33]. Antibodies coupled to fluorochromes are used in the fully automated immunological measurement of platelets [34][35][36][37], T-helper and T-suppressor cells [38,39] and hematopoietic stem cells [40,41]. PCR products can also be detected and quantified in flowthrough cytometry using specific microparticles [42,43].…”

Cytomics – importance of multimodal analysis of cell function and proliferation in oncology

“…2005;Gerstner et al . 2006a), red blood cell analysis (Arndt & Garratty 2004;Greve et al . 2004), rare cell detection , characterization in the case of stem cells (Bou-Gharios et al .…”