Ellipsometric studies in vitro on kinetics of rat complement activation

The role of complement activation may be important during the early interac tions between implantable materials and blood and during the acute inflamma tory phase, but it is not well understood. This applies especially to rats that are extensively used in in vivo animal models for materials and surfac e testing. Features of the kinetics of rat complement activation were studi ed and compared with human complement by the ellipsometry and antibody tech niques. The results indicate that the rat classical pathway is rapidly acti vated, but it is not as fast as the human system. The activation of the alt ernative pathway was observed within 5 min in the rat system and within 15 min for the human. Thus, the observations indicate substantial differences in the kinetics between the two species. This may influence the choice of t he rat experimental model and the tissue response to materials during in vi vo conditions. (C) 1999 John Wiley & Sons, Inc.