Reticulocytes in human preserved blood as control material for automated reticulocyte counters

The authors studied the changes in the percentage of reticulocytes in blood preserved for three weeks. The samples were obtained from healthy adults and stored at 4 degrees C. An automated reticulocyte counter was used for measurements. After one week, the relative percentage of reticulocytes had decreased to around 80% of the initial value, and it reached 60% after three weeks of storage. When the y-axis of plots of the change against time was converted to a log scale, negative correlation was strong (r = -0.9972), and the curve was useful for estimation of the reticulocyte count in preserved blood. Stored blood might be used as a control material for reticulocyte counting by automated methods.