Vascular graft-associated complement activation and leukocyte adhesion in an artificial circulation.
Complement-associated leukocyte adhesion appears to be a consistent in vitro and in vivo finding for many types of polymers; however, very little work has been done on the interaction of leukocytes with vascular graft materials. An in vitro perfusion system was used to study complement and leukocyte activation associated with the following vascular graft materials when tested with human blood: expanded polytetrafluoroethylene (ePTFE), crimped Dacron Bionit (DB) and preclotted Dacron Bionit. A decrease in the total leukocyte concentration with perfusion time was seen for all materials tested, and paralleled leukocyte adhesion to the graft surface as observed by scanning electron microscopy. The most dramatic decrease in leukocyte concentration was observed for the interaction of heparinized whole blood with Dacron. This was due to a selective decrease in neutrophils and monocytes, and was correlated with an increase in both leukocyte adhesiveness and complement activation, as measured by C5a elevation. Inhibiting complement activation by use of the anticoagulant, sodium citrate, curtailed Dacron-induced leukocyte adhesion. Little leukocyte or complement activation was observed for ePTFE or the silicone rubber control regardless of the anticoagulant used.
D000328:Adult; D001807:Blood Vessel Prosthesis; D002448:Cell Adhesion; D003167:Complement Activation; D003182:Complement C5 / Q000032:analysis; D015936:Complement C5a; D006801:Humans; D007957:Leukocyte Adherence Inhibition Test; D007962:Leukocytes / Q000166:cytology*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010477:Perfusion; D011093:Polyethylene Terephthalates; D011108:Polymers; D011138:Polytetrafluoroethylene
D003182:Complement C5; D011093:Polyethylene Terephthalates; D011108:Polymers; D015936:Complement C5a; D011138:Polytetrafluoroethylene