The induction of histamine synthesis from rat bone marrow derived mast cells with rat stem cell factor

Abstract Mast cells are the main cells to produce histamine regarded as the main factor to induce allergy. To comprehend the allergy by mast cell activation, The mast cells of bone marrow derived mast cells (BMMC) are usually prepared by culturing bone marrow cells including rodent hematopoietic stem cells, in the presence of both IL-3 and stem cell factor (SCF). However, BMMC was reported not to produce the high levels histamine comparable to mature mast cells in host tissue. In this study, rat BMMC (rBMMC) were cultured in 96 well plate to induce diverse conditions in cell numbers per unit culture media, rat IL-3 and rat SCF to find the conditions to synthesize high level histamine. Cells of rat bone marrow cells were cultured in the cell density of 1.1×105/ml (low density, lowD) and 5.5 × 105/ml (high D), rat IL-3 was added to the levels of 10 ng/ml (low 3) or 50 ng/ml (high 3), Rat SCF was adjusted to the levels of 12.5 (lows), 25 (midS) and 50 (highS) ng/ml. Histamine included in 5×104 BMMC were extracted by perchloric acid, n-butanol, and heptane. The levels of histamine were measured by ophthalialdehyde solution and read for fluorometric intensity. The levels at culture day 4 (D 4) were in the range of 12~45 ng. The significant elevation was observed at D 11 in the conditions of lowD high3 (153 ng), however, D 8 in highD high3 (253 ng). The average histamine level was 74 ng in the condition of low Dlow 3, but 112 ng in low Dhigh 3 at D 11. That was 106 ng in high Dlow 3 but 183 ng in high Dhigh 3 at culture D 8. These results indicated that rat IL-3 increased the level of histamine synthesis and shorten the histamine production from undifferentiated hematopoietic stem cells. The induction of histamine synthesis from rat bone marrow derived mast cells with rat stem cell factor