[Competitive inhibition of the fixation of various cytotropic antibodies to mast cells of the peritoneal serous membrane in the guinea pig].

The degranulating capacity of guinea pig peritoneal serous membrane mast-cells due to IgG1 and reaginic homocytotropic antibodies and heterocytotropic rabbit IgG antibody was studied, as was the interference which nonspecific immunoglobulins may produce in the fixation of antibodies. Although the capacity to degranulate mast-cells proved identical for all the antibodies studied, reagin appears to possess a greater fixation capacity for a possible cellular membrane site. The greater resistence of reagin to elimination by washing could account for this.