Altered in vitro apoptosis of cultured mast cells prepared from an inbred strain of mice, NC/Kuj

BACKGROUND: An inbred strain of mice, NC, develops dermatitis associated with highly elevated serum IgE and dermal mast cell hyperplasia. OBJECTIVES AND METHODS: To clarify the mechanisms for the dermal mast cell hyperplasia in NC, we prepared bone marrow-derived mast cells (BMMCs) from three strains of mice, NC/Kuj, C57BL/6 and BALB/c, and compare histamine contents, histamine release abilities, adhesive properties and apoptosis of the BMMCs. RESULTS: Compared with BMMCs obtained from C57BL/6 and BALB/c, NC/Kuj BMMC possessed higher histamine content and higher adhesive ability to plastic plates, although histamine release from BMMCs was found to be similar in the three strains. The most intriguing finding is the lack of apoptosis in the BMMCs from NC/Kuj upon growth factor deprivation as determined by DNA ladder formation and loss of membrane phospholipid asymmetry. CONCLUSION: The altered in vitro properties of mast cells in NC/Kuj partially account for an increase of dermal mast cells, which might be involved in the development of skin lesions in NC.