[Advantages of CD45 vs. side scatter based gating in the course of flow cytometric immuno-phenotyping in malignant hematologic diseases].

The application of the CD45 vs. side scatter gating in the flow cytometric immunophenotyping of malignant haematological disorders was investigated. In the course of the conventional double labeling the light scatter based gating is the method of choice, which allows the immunophenotypic characterization of the subpopulations of interest. Using this gating strategy one can separate the lymphocytes, monocytes, neutrophil granulocytes, eosinophils and platelets as distinct cell populations in normal blood samples. The blastic cells present in different malignant hematological disorders might, however, represent an overlapping population with the lymphocytes, NK-cells, monocytes, and nucleated erytroid elements on the FSC vs. SSC histogram, making it difficult or impossible to separate them from the residual reactive cells. This will impart false mixed immunophenotypic property to the blastic cells. The authors found definitive advantages of CD45 vs. SSC gating in contrast to the FSC vs. SSC analysis due to the reliable separation of lymphoblasts, myeloblasts, nucleated erytroblasts as well as the debris from the reactive cell populations. The most plausible application of this method is shown in the course of three-color labeling, applying CD45 as a constant marker. Furthermore, the authors demonstrated that the CD45 vs. SSC gating strategy will result in considerable increase in resolution of blastic population also in the course of the most conventional dual-color labeling method.