The patients were treated for up to six hours with an extracorporeal method consisting of click here a plasma separation and plasma perfusion through the cell-compartment containing the donor cells. Blood access was veno-venous via a Shaldon-catheter. Plasma separation was carried out by a dialysis monitor (BM25, Edwards Lifesciences GmbH, Unterschleissheim, Germany) using a 0.5 ��m pore-size plasma filter (PF 1000N, Gambro Hospal GmbH, Planegg-Martinsried, Germany). The plasma was infused into the continuously re-circulating donor cell compartment. A schematic view of the extracorporeal treatment device is shown in Figure Figure2.2. Plasma reflux to the patient was done through a second PF 1000N plasma filter to withhold the donor cells from being infused into the patient. Total extracorporeal volume was 400 ml.

The blood flow rate was 150 to 200 ml/minute with a plasma separation rate of 16.7 to 33.3 ml plasma/minute using the BM 25 monitor. The MARS-Monitor 1 TC (Gambro Rostock GmbH, Rostock, Germany) was used for the re-circulating bioreactor circuit at a rate of 200 ml/minute and to maintain the temperature in the cell compartment at 37��C. Unfractionated heparin (20 IU/kg, Roche, Grenzach-Wyhlen, Germany) was given at the beginning of the extracorporeal treatment followed by a continuous infusion into the circuit. Heparin administration was adjusted to maintain activated clotting time (ACT) between 150 to 200 seconds. Following tolerability assessment of the first treatment, all patients were treated a second time 48 to 72 hours after the first treatment, again for up to 6 hours with granulocytes from the same donor.

Figure 1Schematic view of the study flow.Figure 2Schematic drawing of the extracorporeal treatment. Plasma is separated from blood, transferred to the cell-compartment, and then returned to the patient.MeasurementsWe recorded basic demographic information, illness severity (Acute Physiology and Drug_discovery Chronic Health Evaluation (APACHE) II, Sequential Organ Failure Assessment (SOFA), Multiple Organ Dysfunction Score (MODS), and Simplified Acute Physiology Score (SAPS) II scores), microbiological results, pre-morbidity, and clinical outcome for the study cohort (see Table Table1).1). Patients were followed up for 28 days and hospital survival. At the days “inclusion”, 1 to 8, 10, 12, 14, 21, 28 and before/after an extracorporeal bioreactor-treatment the patients were screened for clinical and immunological data: hemodynamic, inflammation, coagulation, hemolysis, temperature, organ function blood parameters, endotoxin, cytokines, complement (C3, C4), and the number of human leukocyte antigen DR (HLA-DR) molecules per monocyte surface. “Day 1″ was defined as the day of the first bioreactor treatment.