Monoclonal antibodies against rat mast cells differentiate between subtypes.

Four monoclonal mouse anti rat mast cell antibodies were selected which detect an antigenic determinant occurring on connective tissue mast cells of the rat. A strong antigen density was found on peritoneal mast cells whereas pleural and mesenteric mast cells exhibit considerably smaller amounts of the antigen. It does not occur on lung mast cells and basophils, thus permitting a mast cell subtype differentiation according to the expression of a surface antigen. The monoclonal antibodies do not react with IgE or IgE Fc-receptor determinants and do not interfere with the histamine secretion from peritoneal mast cells.