Mast cells and eosinophils play important roles in many severe allergic and inflammatory diseases of the respiratory, gastrointestinal tracts and the skin.
Diseases in which there is excessive infiltration of mast cells into tissues include:
Aberrant proliferation of mast cells or eosinophils also cause certain rare but debilitating diseases such as systemic mastocytosis and hyper-eosinophilic syndrome, respectively. All of these diseases have a dramatic impact on patients' quality of life and many carry significant morbidity and increased mortality.
Current treatment for a significant proportion of patients with these severe diseases is often inadequate because of limited efficacy as well as significant toxicity.