Abstract
Peripheral blood contamination in human bone marrow aspirates was calculated from the ratios between the erythrocyte and nucleated cell counts in both the bone marrow aspirate and a simultaneously obtained peripheral blood sample. This method is based upon experimental data which showed that the erythrocytes in bone marrow aspirates are mainly derived from the intravascular blood compartment. A strong negative correlation was found between the peripheral nucleated cell fraction (FB1) and the number of myeloid progenitor cells in 65 bone marrow samples (correlation coefficient r = -0.51; p < 0.001). A similar correlation was found between erythroid progenitor cells and peripheral blood fraction (r = -0.55; p < 0.01). The culture conditions were continuously monitored, using large batches of frozen marrow samples as controls