[Degranulation of the mast cells of syngeneic rats induced with sera of rats treated with grafts of methylcholanthrene-induced sarcoma].

The serum of rats immunized by MCA sarcoma graft may cause marked degranulation of the mast cells of syngeneic rats sensitized by a homogenate of cancer cells. The serum of immune rats has also caused more limited degranulation in syngeneic rats that have not been previously sensitized. This phenomenon would appear to be explained by a possible cross reaction of antibodies present in the immune sera with the normal histocompatibility antigens expressed on mast cell membranes.