Extracorporeal granulocyte and monocyte/macrophage adsorption (GMA) using an adacolumn filled with cellulose acetate beads as GMA carriers selectively depletes excess and activated myeloid leucocytes from the circulation and has been used as a non-pharmacologic adjunct therapy in patients with inflammatory bowel disease (IBD). In this study we applied hyperthermic stimulation of blood during exposure to the GMA carriers with the aim of enhancing the release of anti-inflammatory substances from leucocytes. In blood from patients with Crohn's disease (CD) and healthy controls (HC), incubation with the carriers was associated with a striking increase in the release of interleukin-1 receptor antagonist (IL-1ra, a powerful anti-inflammatory cytokine) independent of hyperthermic stimulation, while in the blood from both CD and HC, the release of heat shock protein70 (Hsp70, a cytoprotective protein) was increased by two fold. The present data indicate that hyperthermic stimulation of blood at 43 degrees C or exposure to cellulose acetate carriers is a simple strategy to generate substances of therapeutic potential from blood, especially in patients with IBD. These observations are very interesting in the context of extracorporeal immunomodulation in patients with immune pathology.