Establishment and characterization of a new canine mast cell tumor cell line.

A new cell line (CoMS) was established from a 3-year-old male mongrel dog with mast cell tumor of the oral mucosa. CoMS cells grow in suspension with a doubling time of 27.0 +/- 0.7 hr. The cytoplasmic granules were formalin-sensitive, showed diverse appearances in their ultrastructural findings and contained heparin proteoglycan and neutral protease chymase. Calcium ionophore A23187, substance P and concanavalin A caused significant histamine release from CoMS cells, while compound 48/80 failed to release histamine. This cell line will make an available source for studies on canine mast cell tumors.