Activation of neutrophil granulocytes in an in vitro model of a cardiopulmonary bypass.
Activated neutrophils play a central role in the pathogenesis of postoperative organ dysfunction after surgery with cardiopulmonary bypass. The researchers used an in vitro roller pump model to investigate the relative importance of the biomaterial, platelets, plasma proteins including activated complement, and flow mode on neutrophil activation as shown by the adhesion, degranulation, and increased the surface expression of CD11b. Neutrophil adhesion to the biomaterial increased with platelet addition, but not with plasma. Biomaterial contact activated neutrophils in a serum-free buffer, but was significantly increased by activated complement. Platelets increased neutrophil degranulation in a serum-free buffer but tended to reduce it in plasma. CD11b expression increased in both media. Complement activation was higher with neutrophils alone than with neutrophils and platelets combined. The roller pump reduced neutrophil adhesion and increased degranulation compared to passive rotation. Neutrophil interaction with platelets and complement were more important for activation than biomaterial contact and use of the roller pump. Improvement of biocompatibility is dependent on modifying complement activation and platelet interaction with neutrophils.
Asberg
Ann Elisabeth
AE
Department of Immunology and Transfusion Medicine, Trondheim University Hospital, Trondheim, Norway. ann.asberg@ntnu.no
Videm
Vibeke
V
D000704:Analysis of Variance; D000925:Anticoagulants; D001792:Blood Platelets / Q000378:metabolism; D039481:CD11b Antigen / Q000378:metabolism; D002315:Cardiopulmonary Bypass; D002448:Cell Adhesion; D015550:Cell Degranulation; D015938:Complement Membrane Attack Complex / Q000378:metabolism; D005434:Flow Cytometry; D006098:Granulocytes / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007552:Isotonic Solutions; D007781:Lactoferrin / Q000378:metabolism; D008954:Models, Biological; D018375:Neutrophil Activation; D009195:Peroxidase / Q000378:metabolism; D010949:Plasma; D011143:Polyvinyl Chloride; D015854:Up-Regulation
D000925:Anticoagulants; D039481:CD11b Antigen; D015938:Complement Membrane Attack Complex; D007552:Isotonic Solutions; C037692:Tyrode's solution; D011143:Polyvinyl Chloride; D009195:Peroxidase; D007781:Lactoferrin