Cord–Blood–Derived Human Cultured Mast Cells Produce Interleukin 13 in the Presence of Stem Cell Factor

Background: Mast cells have been regarded as a potential source of cytokines. Although the human mast cell line HMC–1 and human lung mast cells have been shown to produce interleukin (IL) 13, it still remains uncertain whether cord–blood–derived human cultured mast cells produce IL–13. Methods: Human cultured mast cells were raised from cord blood cells in the presence of stem cell factor (SCF) and IL–6. Levels of IL–13 mRNA were examined by a semiquantitative reverse transcriptase–polymerase chain reaction. IL–13 levels in the supernatants were measured with an enzyme–linked immunosorbent assay. Results: When the IgE–sensitized cultured mast cells were activated with anti–IgE, mRNA for IL–13 was amplified with a peak at 3 h after the stimulation. IL–13 was not detected in the supernatants of the activated mast cells in the absence of SCF, whereas the mast cells secreted significant amounts of IL–13 after the stimulation in the presence of SCF. Calcium ionophore A23187 also stimulated the mast cells to release IL–13 into the supernatant in the presence of SCF. Conclusions: These observations suggest that human mast cells can produce IL–13 under the condition with SCF. The cord–blood–derived human cultured mast cells will help in studying the functional properties of human mast cells in allergic diseases.