Novel method of leukocytapheresis using a highly concentrated sodium citrate solution alternative to acid citrate dextrose solution A

Background: Large-volume leukocytapheresis is time consuming. The upper limit of the inlet flow rate is determined by the inlet: anticoagulant (AC) ratio and can be changed by combining the AC with heparin. Here, we devised a protocol to increase the AC ratio using a highly concentrated sodium citrate solution without heparin.
Study Design and Methods: We collected data from 40 consecutive apheresis procedures performed using the Spectra Optia system on 40 donors for allogeneic peripheral blood stem cells between June 2022 and June 2023. We used AC containing 2.2% sodium citrate (normal concentrated sodium citrate [NSC]) and 5.32% sodium citrate (highly concentrated sodium citrate [HSC]). The AC ratios were set to 12:1 and 24:1 for the NSC and HSC, respectively.
Results: The processed volume was not different; the maximum inlet flow rate increased, the total processing time was reduced, the AC solution used was reduced, and the product volume was reduced in the HSC group, compared to the NSC group. Although the CD34+ cell CE2 was reduced in the HSC group, no difference was observed in the number of collected CD34+ cells. The incidences of citrate-related reactions were similar.
Discussion: We propose a novel leukocytapheresis method using HSC that shortens the procedure time and reduces the amount of AC solution used compared to the conventional method