LEUKOCYTE FILTERABILITY - COMPARING DILUTED BLOOD WITH PURIFIED CELL-SUSPENSIONS

Current theological trends in filtration studies involve purification of cell subpopulations in order to study near-homogenous populations o f cells, and this means that time-consuming and possibly cell-damaging procedures are used. Filtration of diluted blood offers the possibili ty of determining the properties of subpopulations of cells with minim al cell manipulation. The filtration properties of granulocytes and ly mphocytes result in their being detected as one kinetic population, an d therefore a combined granulocyte/lymphocyte pore transit time is cal culated. There was no significant change seen in the combined granuloc yte/lymphocyte transit time over the normal range of differential coun t, Filtration of diluted blood is a more reproducible way of measuring granulocyte and lymphocyte filterability, because purification of the se cells gives rise to more scatter and larger ranges in the measured pore transit time, and significant day-to-day variation. A combined gr anulocyte/lymphocyte transit time is therefore an acceptable and repro ducible way of assessing leucocyte rheology in diluted blood, when the differential count lies within the normal range, If changes in the gr anulocyte/lymphocyte transit time are detected, then cell purification may yield additional information on the subpopulations. Therefore, pa rticularly in pathological samples, a combination of these approaches will yield more information than either test alone.