Flow cytometry in transfusion medicine: an overview

Abstract

Background Flow cytometry has been used in many different settings to, for example, analyse subpopulations of leucocytes in quality control of stem cell grafts and in the diagnosis of lymphoma and leukaemia. In transfusion medicine, it has mainly been utilized for detection and semiquantification of various blood group antigens as a complement to traditional serology, for quality control of blood components and detection of fetomaternal haemorrhage. Today, when flow cytometers are becoming smaller, cheaper and more user friendly and are available in many routine laboratories, the method should be considered as a valuable tool to use in addition to serology and genomic typing.Objectives To give an overview of how flow cytometry can be useful in a transfusion medicine setting as a complement to both traditional serology and molecular testing.Conclusion Flow cytometry has the advantages of a higher sensitivity for some antigens than in traditional serology and the ability to easily distinguish between two or more populations of cells, which makes it a useful tool in many clinical settings, for example in defining chimeras and in detection of fetomaternal bleeding. The combination of molecular testing and the detection of surface antigens by flow cytometry are found useful. When resolving clinically relevant ABO discrepancies we have found the combination of genetic testing and semiquantification of ABO antigens by flow cytometry very helpful. Taken together flow cytometry is a handy tool in clinical routine analysis as well as in research focusing on transfusion medicine.

A report on a modified protocol for flow cytometry‐based assessment of blood group erythrocyte antigens potentially suitable for analysis of weak ABO subgroups

“…Since the series of pioneering work, 6,11,18 FC assays have been proving their utility in many aspects of transfusion medicine, 9,10,19,20 including the analysis of weak ABO subgroups that would show ABO discrepancy in serological tests. 7,8 Regarding the ABO variants characterized by small amounts of antigens, for example, the A el and B m subtypes, it is generally believed that their presence can only be demonstrated by an adsorption-elution test, which is the most sensitive serological technique.…”

“…The detailed characterization of the group antigens O (H), A, and B on the surface of red blood cells (RBCs) remains critical in the area of transplantation and transfusion medicine 4 . Flow cytometry (FC) analysis has contributed significantly to medical sciences as a powerful analytical platform with its simplicity and high sensitivity; 5 it has also shown to be utilized for ABO blood typing purposes 6–13 . Here, we report the establishment of an FC protocol potentially suitable for detecting a small fraction of RBCs weakly expressing AB antigens.…”

“…4 Flow cytometry (FC) analysis has contributed significantly to medical sciences as a powerful analytical platform with its simplicity and high sensitivity; 5 it has also shown to be utilized for ABO blood typing purposes. [6][7][8][9][10][11][12][13] Here, we report the establishment of an FC protocol potentially suitable for detecting a small fraction of RBCs weakly expressing AB antigens. We showed that the assay could identify antigen dull-positive RBCs existing at a low frequency in a B m subgroup sample (1%) and an A el subgroup sample (0.04%), with only limited background noise levels (≤0.01%) allowed for negative control samples.…”

Slot blotting and flow cytometry: two efficient assays for platelet antibody screening among patients with platelet refractoriness

“…Previous experiments introduced chloroquine treatment of platelets to dissociate HLA class I antigens without affecting HPA antigens [17,18]. Flow cytometry (FC) is already known to be a reliable technique that has been widely used to detect antigens/antibodies on the cell surface through measurement of the fluorescence intensity emitted from an excited fluorochrome-conjugated antibody [19,20]. However, the analysis conducted using this method is subjective and needs skilled personnel and expensive instrumentation.…”

Rh flow cytometry: An updated methodology for D antigen density applied to weak D types 164 and 165

“…30 Some weak D types, such as type 10 (W393R), 31 type 18 (R7W), [32][33][34] and type 31 (P6L), 35,36 are known to present with irregular quantitative expression of the D antigen, such as mixed-field agglutination during serologic testing or as multiple red cell populations on flow-cytometric histograms. This phenomenon of mixed-field reactivity in blood group antigens has been explained over the years by several mechanisms including transcriptional noise, 37 red cell chimerism, 38,39 maternal-fetal hemorrhage, 40 or sample preparation error during flow cytometry. 41 As novel blood group alleles continue to be identified, comprehensive genetic and serologic descriptions are standard practice.…”