Potential role of stem cell factor in the asthma control by glucocorticoids.

Asthma is an allergic disease characterized by inflammation that includes an increase in the number and activation of mast cells in the airways. Glucocorticoids, on the other hand, diminish inflammation as well as the number of mast cells in this disease. Stem cell factor (SCF) is a major growth factor for human mast cells, inducing chemotaxis as well as survival of the mast cells. SCF induces proliferation and differentiation of immature mast cells from CD34+ progenitors. It also potentiates the IgE-dependent activation of mast cells. Furthermore, SCF expression is reduced in the airways of asthmatic patients treated with glucocorticoids. Thus, SCF could be involved in mast cell-associated diseases such as asthma. We here review the main effects of glucocorticoids in asthma and on mast cells, with a special interest on SCF, as a potential therapeutic target in asthma.