COMPLEMENT ACTIVATION BY CELLULOSE - INVESTIGATION OF THE EFFECTS OF TIME, AREA, FLOW-RATE, SHEAR RATE AND TEMPERATURE ON C3A GENERATION IN-VITRO, USING A PARALLEL-PLATE FLOW CELL

The development and utilization of a parallel plate flow system to stu dy the blood response to flat sheet biomaterials, is described. Unlike most other parallel plate flow systems, which have been used to study cellular interactions with biomaterials, the controlled flow test cel l described below employs the test materials on both sides of the chan nel through which the blood flows. The flow cell is used to conduct an investigation into the in vitro generation of C3a by a regenerated ce llulose membrane, Cuprophan. The effects of experimental variables suc h as temperature, blood flow rate, contact area and wall shear rate on C3a generation by Cuprophan were studied. The results show that C3a g eneration by Cuprophan is lower at 12 degrees C than at 22 degrees C, which is in turn lower than C3a generation at 37 degrees C. Furthermor e, a decrease in contact area, and increase in wall shear rate and blo od flow rate, can produce a decrease in C3a concentration.