| Immune complexes (IC) and C5a anaphylatoxin are important humoral mediators of the acute inflammatory response. These agents, together with neutrophils, are thought to be responsible for many of the salutary and deleterious effects seen in inflammatory conditions. However, IC-PMN and C5a-PMN phenomena have traditionally been studied in vitro as separate entities. This thesis sought to examine and characterize model IC interactions with human PMN in vitro and evaluate the effect of human C5a anaphylatoxin on these interactions.;Model IC are composed of human desArg;Detailed characterization of the intracellular degradation of desArg;The effect of human C5a anaphylatoxin on model IC-PMN interactions is examined. The anaphylatoxin augments surface expression of neutrophil Fc;Although human neutrophils are not antigen-presenting cells, the sequential degradation of IC and the generation of small epitopic regions of antigen suggest that an analogous process in immune-capable cells would be a facile means for generating relevant antigenic epitopes. Additionally, C5a may enhance an inflammatory response by increasing the surface expression of biologically important receptors and subsequently augmenting cellular responses to other humoral mediators. |
