Complement activation by PVA as measured by ELIFA (enzyme-linked immunoflow assay) for SC5b-9

Polyvinyl alcohol (PVA) coated onto polyethylene (PE) tubes exposed to huma n serum for 1 hour at 37 degrees C resulted in the production of 1.03 +/-0 0.04 mu g/cm(2) of the soluble form of the terminal membrane attack complex , SC5b-9. This was approximately 20 x that produced by the polyethylene. Ab out one quarter of this total was found associated with the surface of PVA. SC5b-9 concentrations were determined by enzyme-linked immunoflow assay (E LIFA) a variant on ELISA that involved drawing the test sample, the antibod ies and the chromogenic reagent through a nitrocellulose membrane filter. E LIFA enabled analysis of protein concentrations in the presence of SDS, so that SDS (0.05 %) was used to desorb adsorbed SC5b-9 prior to analysis toge ther with SC5b-9 in the bulk to get a more complete picture of PVA-associat ed complement activation. (C) 2000 Elsevier Science Ltd. All rights reserve d.