ASTHMA IS AN INFLAMMATORY disease of the airways. Prominent effector cells of this inflammatory response include mast cells, eosinophils, and neutrophils, and, as such, understanding the contribution of secreted mediators from these cells to the pathophysiology of asthma has been the subject of intense investigation. Human mast cell tryptases (EC 3.4.21.59) comprise a family of trypsin-like neu...

Mast cells (MCs) expressing serine proteases; tryptase and chymase, are associated with fibrosis in various diseases. However, little is known about their involvement in oral submucous fibrosis (OSF). Our goal was to evaluate the role of MC tryptase and chymase in the pathogenesis of OSF and its malignant transformation. Immunohistochemical expression of MC tryptase and chymase was evaluated in...

Severe intraoperative hypotension has been reported in patients on angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists. We describe a patient on lisinopril who developed refractory intraoperative hypotension associated with increased serum tryptase level suggesting mast cell activation (allergic reaction). However, allergology workup ruled out an allergic ...

Human lung tryptase, a homotetrameric serine protease unique to mast cell secretory granules, has been implicated in the pathogenesis of asthma. A hypothesis that tethered symmetrical inhibitors might bridge two adjacent active sites was explored via a rationally designed series of bisbenzamidines. These compounds demonstrated a remarkable distanced-defined structure-activity relationship again...

Tryptase is a serin protease stored in mast cell granules that has recently been found to be involved in tumor angiogenesis. Data from experimental tumor models have suggested that prior to the onset of angiogenesis mast cells were accumulated near tumor cells and were required for the macroscopic expansion and metastatic spread of primary tumor cells. Hepatocellular cancer (HCC) is a well-esta...

BACKGROUND Mastocytosis is a clonal disorder characterized by the accumulation of abnormal mast cells in the skin and/or in extracutaneous organs. OBJECTIVES To present all cases of mastocytosis seen in the Porto Hospital Center and evaluate the performance of World Health Organization diagnostic criteria for systemic disease. METHODS The cases of twenty-four adult patients with mastocytosi...

BACKGROUND Rupture in the shoulder region of a coronary atheroma is considered to be a sequel to local extracellular matrix degradation in this highly vulnerable site. Such degradation could be triggered by mast cells, which are filled with neutral proteases and are present in coronary atheromas. However, the distribution and phenotype of mast cells within coronary atheromas have not been studi...

Seasonal allergic rhinitic (SAR) subjects are more sensitive to nasal irritants than nonrhinitic (NR) subjects; however, the mechanism underlying this difference is unclear. This study sought to determine whether irritant-induced nasal congestion involves mast cell degranulation. Eight SAR and eight NR subjects were exposed to both 1.0 parts per million chlorine and filtered air in separate vis...

Mast cell infiltration of tumour islets represents a survival advantage in non-small cell lung cancer (NSCLC). The phenotype and activation status of these mast cells is unknown. We investigated the mast cell phenotype in terms of protease content (tryptase-only [MCT], tryptase + chymase [MCTC]) and tumour necrosis factor-alpha (TNFα) expression, and extent of degranulation, in NSCLC tumour str...

Pancreatic cancer is a highly lethal malignancy and one of the leading causes of cancer-related death. During the development and progression of cancer, tumor angiogenesis plays a crucial role. A great deal of evidence has revealed that human mast cells (MCs) contributed to tumor angiogenesis through releasing several pro-angiogenetic factors, among which tryptase is one of the most active. How...