Effects of culture matrix on differentiation of murine mast cells

The effects of culture matrix (agar, collagen, and methylcellulose) on differentiation of mast cells were investigated. Because berberine sulfate-positive colonies in agar were composed of macrophages but not of mast cells, the naphthol AS-D chloroacetate esterase reaction was used to identify mast-cell colonies. When bone marrow cells of WBB6F1 mice were cultured with conditioned media containing interleukin 3 (IL-3), numbers of mast-cell colonies were greater in collagen cultures than in agar and methylcellulose cultures. Electron microscopic examination revealed that mast cells developing in collagen and agar cultures were more mature than those developing in methylcellulose cultures. However, when bone marrow-derived cultured mast cells or purified peritoneal mast cells were plated, the efficiency of colony formation and size of colonies were comparable among agar, collagen, and methylcellulose cultures. Therefore, all three matrices tested had similar effects on the proliferation of mast cells. Collagen appeared to be suitable for differentiation of bone-marrow precursors and their maturation. Agar appeared to be suitable only for maturation.