10(6) Depletion of WBC with CF-2, a new leukocyte removal filter

A new leukocyte removal filter, Nipro CF-2, was evaluated. A non-woven polyester filter, gravity flow device that does not require priming and rinsing after use was developed to remove white blood cells from 400 ml of whole blood or concentrates of 400 ml of whole blood. A flow cytometric technique was developed to measure extremely low WBC counts. To evaluate the efficiency of this filter, leukocyte counts were measured by flow cytometry using a Coulter EPIC-C cytometer. After filtration through a CF-2 filter, more than 99.9999% of WBCs were depleted from 6 of 17 samples. The mean value of WBC depletion was 99.9994%. The CF-2 filter achieved nearly a million-fold depletion of WBCs from whole blood concentrates.