[Responsible agents and mechanisms of direct allogeneic anaphylactic degranulation].

Because mast cells from inbred mice possess both H-2 Ag and Fe receptors they can be degranulated by anaphylactic allo-Ab (DAAD). Beside IgG1, IgE allo-Ab were shown to exist and to be able to achieve DAAD. So far, to be the target of DAAD, an Ag must be present on the mast cell membrane and presumably not linked to the Fe receptor. The mechanism of DAAD involves very likely a double interaction of the Ab (by its two reactive ends) with the mast cell membrane.