2011 Volume 2 Issue 1 Pages 97-103
[Background] The high mobility group box 1 protein (HMGB1) is an alarmin of lethal systemic inflammation. Thus, HMGB1 has been recognized as a therapeutic target；however, no drugs or devices are currently in practical use. We hypothesized that hemofilters composed of porous or cytokine-adsorbing membranes could remove HMGB1 from the blood. [Methods] The test solution contained 100μg of HMGB1 and 35g of albumin in 1000mL of a substitution fluid. Experimental hemofiltration was conducted for 360min in a closed loop circulation system, and the sieving coefficient (SC) and ultrafiltrate and solution clearance rates of HMGB1 were calculated. We selected internationally available membranes：high cut-off (HCO), surface-treated polyacrylonitrile (AN69ST), three types of polymethylmethacrylate (PMMA), two types of polysulfone (PS) membranes and tubing were tested. [Results] AN69ST showed the highest capacity to adsorb HMGB1；it adsorbed nearly 100μg of HMGB1 in the initial 60min and showed a markedly high clearance rate of 60.8±5.0mL/min at 15 min. PMMA membranes, N, SX and BG, showed rates of 25.8±4.8, 23.3±8.3 and 24.0±8.9 mL/min, respectively. FX, SH and HCO showed rates of 7.0±9.1, 10.1±5.7 and 18.7±4.4mL/min, respectively. Although the highest sieving coefficient for HMGB1 was obtained with HCO, which correlated with a constant filtrate clearance rate, albumin loss was observed. [Conclusion] This is the first in vitro study to demonstrate that the adsorption mechanism of hemofiltration is the most important principle to remove HMGB1.
