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Regulation of mast cell differentiation studied using the diffusion chamber technique.

A homogeneous population of mast cells was obtained by culturing bone marrow cells of WBB6F1(-)+/+ mice. The proliferation of the cultured mast cells in diffusion chambers was investigated to examine whether the diffusion chamber technique was applicable for study of the regulation of mast cell proliferation. WBB6F1-W/Wv mice are genetically deficient in mast cells. When cultured mast cells of WBB6F1(-)+/+ mouse origin were directly injected into the peritoneal cavity of WBB6F1-W/Wv mice, the mast cells survived. In contrast, WBB6F1(-)+/+ mouse-derived cultured mast cells did not survive in diffusion chambers implanted in the peritoneal cavity of either WBB6F1-W/Wv or WBB6F1(-)+/+ mice. Because the coinoculation of NIH/3T3 cells supported the proliferation of mast cells in diffusion chambers, a certain type of cells in the peritoneal cavity appeared to have the same mast cell-supporting activity as NIH/3T3 cells. The magnitude of either interleukin 3-dependent or NIH/3T3 cell-dependent proliferation of mast cells in diffusion chambers was not significantly influenced by the genotype of chambers recipients (i.e., WBB6F1(-)+/+ or WBB6F1-W/Wv mice), suggesting that the previously reported inhibitory effect of mast cells on differentiation of mast cells may be mediated by direct contact between mast cells.