PLASMA LEUKEMIA INHIBITORY FACTOR, INTERLEUKIN-6 AND SOLUBLE INTERLEUKIN-6 RECEPTOR LEVELS DURING CARDIOPULMONARY BYPASS WITH EXTRACORPOREAL-CIRCULATION

In this study the authors assessed plasma leukaemia inhibitory factor (LIF), interleukin 6 (IL-6) and soluble IL-6 receptor (sIL-6R) concent rations in 28 patients undergoing coronary artery bypass graft (CABG) with extracorporeal circulation (ECC), Plasma IL-6 levels increased du ring ECC, reaching a 33-fold increase 6 h after surgery as compared to pre-operative values. In contrast, plasma sIL-6R and LIF concentratio ns did not vary significantly during cardiac surgery. Thus, LIF is not implicated in the haematological changes and in the inflammatory synd rome observed after CABG. Despite the fact that LIF and IL-6 exhibit s everal common biological activities, the production of these two cytok ines is differently regulated during cardiac surgery with ECC, Plasma IL-6 levels increased during cardiac surgery while sIL-6R levels did n ot changed, These data contrast with the decreased sIL-6R concentratio ns with concomitantly high IL-6 levels in patients with sepsis syndrom e suggesting that inflammatory reactions in sepsis and after cardiopul monary bypass are triggered by different mechanisms. (C) 1998 Academic Press Limited.