Flow Cytometric Measurement Of DNA S-Phase In Human Mononuclear Bone Marrow Cells; Estimating The Degree And Correcting For Peripheral Blood Contamination.
J. Foss Abrahamsen*, R. Smaaland, O.D. Laerum, Dept. of Pathology, and Dept. of Oncology, Haukeland Hospital, University of Bergen, Norway.
Mononuclear bone marrow (BM) cells from hematologically healthy individuals were labelled with CD45, which differentiates cells into erythroid, myeloid and lymphocyte + monocyte subpopulations according to increasing immunofluorescence intensity expression. Thereafter a hypotonic propidium iodide solution was added, and DNA cell cycle characteristics of the total cells and subpopulations was obtained. Mixing BM aspirates with increasing amounts of peripheral blood from the same donor, resulted in increasing amounts of lymphocytes + monocytes and decreasing S-phase. In 136 BM aspirates and biopsy expellates, with varying amounts of peripheral blood contamination, a significant negative correlation was demonstrated between total, erythroid and myeloid BM cells in S-phase and the percentage of L + MO in the aspirates (R = 0.84, 0.57 and 0.49, respectively; p<0.0001). Based on the equation of the slope of the regression line, a correction formula adjusting the measured value of BM cells in S-phase to varying amounts of L + MO percentage, has been worked out. This method is especially applicable when frequent sampling is required for repeated BM cell kinetic investigations.