HYPOTHESIS: Because many of the biologic phenomena in which mast cells are involved also are observed in @entity1 @entity3540 pathology, the authors hypothesized that mast cells may play a role in this disease. The first test of this hypothesis is to determine whether there are an increased number of mast cells associated with @entity3540 . BACKGROUND: The molecular and cellular defects that result in the pathologic features observed in acquired and congenital @entity3540 are unknown. One common feature of @entity3540 pathogenesis is the presence of bacteria and a numerous inflammatory cytokines expressed by host inflammatory cells. The interactions between inflammatory cells and @entity3540 epithelium could result in the induction of other aberrant biologic features of @entity3540 . Thus, it is critical to the understanding of the pathogenesis of @entity3540 to define the specific role of each cell type involved in this disease. Connective tissue mast cells have a complex retinue of functions mediated via the secretion of a variety of cytokines and proteinases, and many of the biologic phenomena in which mast cells are involved also are observed in @entity3540 pathology. METHODS: The authors evaluated by immunohistochemistry 36 @entity3540 of all types (e.g., primary and secondary acquired, recurrent, and congenital) and 23 specimens of normal tissues (e.g., tympanic membrane, canal wall skin, and postauricular skin) for the expression of tryptase, a mast cell-specific protease. RESULTS: @entity3540 showed approximately threefold to sevenfold increase in the concentration of mast cells when compared with that of normal tissues. In addition, 19-34% of the mast cells were found within the suprabasal layers of the squamous epithelium of @entity3540 subgroups, a phenomenon observed only in grossly inflamed tympanic membrane specimens, but not in other control tissues including minimally inflamed tympanic membranes. CONCLUSIONS: The authors conclude from these data that mast cells may represent a previously unrecognized host inflammatory cell, which plays an important role in the development of one or more traits of @entity3540 pathology.

Increased numbers of mast cells in XXXX middle ear cholesteatomas: implications for treatment.

@entity1 :: ('9606', 'Species') :: ['human'] @entity3540 :: ('MESH:D002781', 'Disease') :: ['cholesteatoma', 'cholesteatomas', 'Cholesteatomas']
@entity1 :: (9606,Species) :: ['human']
