The preparation of leukocyte-poor concentrated red cells(CRC) by sepacell-R500 filter. Effect of storage periods of CRC on leukocyte removal.

Abstract

We examined the effect of storage periods of CRC on leukocyte removal by Sepacell-R500 filter using fluorescence staining method to determine small numbers of leukocytes in filtrated CRC. The CRCs prepared from 400 ml of whole blood and stored for 0, 2 and 10 days were passed through Sepacell-R500 by gravity or at a flow rate for blood transfusion (4 ml/min) without priming the filter and suspending CRC with saline. Sepacell-R500 removed more than 99.9% of the leukocytes (the residual leukocyte numbers: less than 8 X 105) while 89-98% of red cells were recovered from one unit of CRC. There were no significant differences between the pre-and post-filtered red cells in cell volume, osmotic fragility, free hemoglobin contents in supernates, the levels of ATP and 2, 3-DPG and morphological change. The removal rates of leukocytes by the filter were unchanged between the CRC stored for 2 and 10 days. In the case of fresh CRC filtrated through by gravity, the leukocyte removal rate was 95-96% and the remaining leukocytes in the CRC were mostly granulocytes. The phenomenon was due to the higher flow rate and lower granulocyte adhesion than those of CRC stored for 2 and 10 days. On the other hand, the leukocyte removal rate was about 99.9% when fresh CRC was filtrated at the rate of 4 ml/min. The filtration procedure at the patient's bedside was excellent for the prepration of leukocyte-poor CRC regardless of storage periods.