Antithrombin reduces monocyte and neutrophil CD11b up regulation in addition to blocking platelet activation during extracorporeal circulation

• Published in: Transfusion (Philadelphia, Pa.) Vol. 46; no. 7; pp. 1130 - 1137
• Main Authors: Rinder, Christine S., Rinder, Henry M., Smith, Michael J., Fitch, Jane C.K., Tracey, Jayne B., Chandler, Wayne L., Rollins, Scott A., Smith, Brian R.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-07-2006; Blackwell Publishing
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Antithrombin III - pharmacology; Biological and medical sciences; Blood coagulation. Blood cells; Blood. Blood and plasma substitutes. Blood products. Blood cells. Blood typing. Plasmapheresis. Apheresis; CD11b Antigen - drug effects; CD11b Antigen - genetics; Emergency and intensive cardiocirculatory care. Cardiogenic shock. Coronary intensive care; Extracorporeal Circulation - adverse effects; Extracorporeal Circulation - methods; Fundamental and applied biological sciences. Psychology; Humans; Inflammation - etiology; Inflammation - prevention & control; Intensive care medicine; Medical sciences; Models, Biological; Molecular and cellular biology; Monocytes - immunology; Neutrophils - immunology; Platelet; Platelet Aggregation Inhibitors - pharmacology; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Up-Regulation - drug effects; Up-Regulation - genetics; Platelet; Transfusion; Neutrophil; Monocyte; Antithrombin
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1111/j.1537-2995.2006.00861.x

BACKGROUND:  Patients undergoing cardiac surgery requiring cardiopulmonary bypass develop a systemic inflammatory reaction. Antithrombin III (AT) has anticoagulant effects but also shows evidence of anti‐inflammatory activity. The aim of this study was to examine whether exogenous AT could reduce white blood cell activation (CD11b up regulation or elastase release), in addition to inhibiting platelet (PLT) activation and fibrin generation, during simulated cardiopulmonary bypass (sCPB), undertaken in the absence of endothelium.
STUDY DESIGN AND METHODS:  sCPB was carried out with minimally heparinized (2 U/mL) human blood for 90 minutes in controls and with supplementation by low‐dose (1 U/mL) and high‐dose (5 U/mL) AT.
RESULTS:  High‐dose AT blunted thrombin generation during sCPB (prothrombin fragment 1.2); both doses significantly inhibited thrombin activity (fibrinopeptide A). Complement activation (C3a and C5b‐9) was unaffected by AT. High‐dose AT inhibited PLT activation (P‐selectin expression and P‐selectin–dependent monocyte‐PLT conjugate formation). AT supplementation at the higher dose significantly abrogated monocyte and neutrophil CD11b up regulation and neutrophil elastase release.
CONCLUSION:  In addition to anticoagulant and anti‐PLT effects, pharmacologic AT doses significantly blunted monocyte and neutrophil CD11b up regulation and neutrophil elastase release during sCPB, independent of endothelial effects. These data provide evidence for the direct anti‐inflammatory activity of AT that has clinical relevance for CPB complications.