We have previously shown the development in vitro of tryptase+ human mast cells from fetal liver cells cocultured with murine 3T3 fibroblasts. In this study, recombinant human stem cell factor (rhuSCF), the ligand for the c-kit proto-oncogene product called Kit, stimulated the growth and differentiation primarily of mast cells from dispersed fetal liver cells, whereas recombinant human interleu...

Numerous mast cells are present in the choroid, but the effects of mast cell mediators on retinal pigment epithelial (RPE) cells are not well understood. We investigated the influence of mast cell mediators on RPE cells in vitro, focusing on tryptase. Expression of receptors was examined by the reverse transcription polymerase chain reaction. We also assessed production of interleukin 8 and vas...

BACKGROUND Telogen effluvium (TE) is a type of acquired, diffuse alopecia that occurs due to an abnormal shift of scalp hair follicles from anagen to telogen, leading to premature shedding of hair. Previous studies have suggested the existence of a neuroimmunologic "brain-hair follicle" axis, in which mast cells have been implicated as an important link between the nervous system and immunologi...

To investigate the role of mast cells in treatment-associated adverse reactions in patients with onchocerciasis, changes in plasma tryptase levels and skin mast cell counts were examined in 2 groups of Onchocerca volvulus-infected subjects after ivermectin treatment. After treatment, an increase in tryptase levels was observed concurrent with the onset of blood eosinopenia and preceding the app...

Tryptase (alpha and beta) levels in serum are used to assess mast cell involvement in human disease. Using cultured cells, the current study examines the hypothesis that protryptase(s) are spontaneously secreted by mast cells at rest, whereas mature tryptase(s) are stored in secretory granules until their release by activated cells. HMC-1 cells have only beta-tryptase genes and the correspondin...

Renal interstitial fibrosis is characterized by increased proliferation of fibroblasts and excessive accumulation of extracellular matrix. Mast cell tryptase has been implicated in the development of tissue fibrosis in skin and lungs. However, the significance of mast cell tryptase in human renal diseases has not been investigated. The potential role of mast cell-derived tryptase in the develop...

PURPOSE Myelomastocytic leukemia is a term used for patients with advanced myeloid neoplasms, in whom elevated numbers of immature atypical mast cells are found, but criteria for a primary mast cell disease are not met. The origin of mast cells in these patients is presently unknown. PATIENT AND METHODS We have analyzed clonality of mast cells in an 18-year-old patient suffering from acute my...

PROBLEM Mast cells are critical in allergic and inflammatory diseases such as interstitial cystitis, which is often clinically associated with or mistaken as endometriosis. Mast cells had previously been reported to be increased at sites of endometriosis, and tryptase may contribute to the fibrosis and inflammation characterizing endometriosis. METHOD OF STUDY This is a pilot study of mast ce...

Recent evidence suggests that nonadrenergic airway relaxation may be controlled by vasoactive intestinal peptide (VIP). The magnitude and duration of smooth muscle relaxation in response to VIP may be influenced by rates of peptide degradation after release from efferent peptidergic neurons. To explore the potential role of mast cell mediators in modulating neural control of airway tone, we stu...

statement of the problem: soft tissue reactive lesions are the most common lesions of the oral cavity. although many studies have shown the interaction of mast cells with fibroblasts and their participation in fibrosis, the role of mast cells in these lesions is not well understood. purpose: the aim of this study was to evaluate the mast cells (mcs) count in oral soft-tissue reactive lesions in...