Impact of an Asymmetric Cellulose Triacetate (ATA) Membrane on Interleukin-6 Clearance and Pressure Stability During Continuous Hemofiltration in an Ex Vivo Sepsis Model

Background: Asymmetric cellulose triacetate (ATA) membranes have been developed to improve filtration performance and biocompatibility in blood purification therapy. However, their efficacy in cytokine removal and their long-term durability have not been comprehensively evaluated. Methods: An ex vivo sepsis model was established by incubating human whole blood samples with lipopolysaccharide for 12 hours. Two hemofilter types, ATA and conventional cellulose triacetate (CTA), were compared using a continuous hemofiltration circuit. Interleukin (IL)-6 levels and albumin clearance were measured over 24 hours. The intracircuit pressure was monitored to evaluate the membrane durability. Results: The ATA membrane achieved significantly higher IL-6 clearance (mean 20.7 (IQR, 17.5-24.5) mL/minute) than the CTA membrane (mean 12.6 (IQR, 10.2-14.9) mL/minute; p = 0.0125). The ATA membrane also demonstrated greater albumin clearance than the CTA membrane (mean 0.74 (IQR, 0.42-0.92) mL/minute vs. mean 0.09 (IQR, 0.07-0.10) mL/minute; p = 0.0039). The ATA membrane demonstrated more stable transmembrane pressure profiles than CTA membranes across the 24-hour observation period. Conclusion: ATA membranes exhibit enhanced cytokine removal capacity and favorable pressure stability compared with conventional CTA membranes. These findings suggest the potential clinical utility of ATA membranes in conditions requiring efficient mediator clearance, although albumin loss should be carefully considered.