Physiological heating augments the anti‐inflammatory reactions during granulocyte/monocyte apheresis: A in vitro study

Granulocyte and monocyte adsorptive apheresis (GMA), an effective therapy for inflammatory disorders, exerts an anti‐inflammatory influence by utilizing the biological reaction between blood and cellulose acetate (CA) beads, which are the carriers of the GMA column. Although the biological reaction has an optimum temperature, blood contacts the CA beads below body temperature as GMA is performed in an extracorporeal circulation system. We investigated various soluble factors in blood treated with CA beads at 25°C and 37°C. Here, the optimal temperature for IL‐1 receptor antagonist (IL‐1ra) release induced by CA beads was 37°C, and IL‐6 production from monocytic cells was inhibited by the addition of plasma prepared from the CA bead‐treated blood at 37°C, rather than at 25°C. These results indicated that physiological heating of the apheresis carrier augmented the anti‐inflammatory reaction in vitro. Thus, heating during GMA may be a new approach for augmenting clinical efficacy.