Figure 5.

Schematic representation of two different strategies to deplete mast cells. Several classes of KIT-associated tyrosine kinase inhibitors (TKIs) are now available [16,260,261]. Preliminary evidence indicates that prolonged administration of imatinib [262] and masitinib [263,264] can influence airway hyperresponsiveness or reduce asthma exacerbations in asthma patients. These beneficial effects have been tentatively attributed to the inhibition of mast cell activation and/or depletion of mast cells. Another approach to induce mast cell apoptosis is through blockage of SCF-KIT interaction. CDX-0159 is a mAb that targets the extracellular dimerization domain of KIT [258,259] and causes a marked reduction of peripheral blood tryptase, suggesting systemic mast cell depletion (NCT04146129).