Binding properties of mechanically and enzymatically isolated hepatocytes for IgG and C3

Abstract

The presence of Fc and [complement] C3 receptors was studied on mechanically and enzymatically isolated rabbit, mouse and rat hepatocytes and on hepatocytes derived from primary cultures. The same cell preparations were used for studying the uptake of an antibody against nuclear antigens. Mechanically isolated hepatocytes were able to bind AIgG [aggregated IgG] and activate complement [C]. However, the same cells were not able to form rosettes with EAC [erythrocyte-antibody-complement] or EA [erythrocyte-antibody]. Enzymatically isolated hepatocytes did not bind AIgG or activate C, nor did they form rosettes with EA or with EAC. The mechanically isolated cells and the nonviable fraction of the enzymatically isolated cells showed a nuclear fluorescence when incubated with an antibody against nuclear antigens. Enzymatically isolated hepatocytes apparently lack Fc and C3 binding sites. Furthermore, the damage to the plasma membrane of the nonviable cells allows the penetration of antibodies against intracellular antigens.