Studies in both human and mouse indicate that mediators released by mast cells can lead to bronchoconstriction, and thus these are important effector cells in life threatening anaphylaxis. Much of our understanding of the various functions of mast cells emanates from the study of mice lacking theses cells, particularly mice carrying mutations in the tyrosine kinase gene Kit. Definitive evidence for the role of mast cells in the altered immune response requires the demonstration that this response can be normalized by reconstitution of the mice with cultured bone marrow-derived mast cells (BMMCs). While many mast cell niches can be restored with BMMCs, this has not been demonstrated for mast cells present in the airways of the lung, cells poised to mediate bronchoconstriction during allergic responses
