Recent studies suggest that mast cell-derived neutral proteases can activate matrix-degrading metalloproteinases (MMPs). We have investigated the role of the mast cell proteases tryptase and chymase in the activation of MMPs in human carotid endarterectomy specimens (atherosclerotic, n=32) and postmortem carotid arteries (control, n=17). In vitro degranulation of mast cells in atherosclerotic c...

The diverse physiological functions of histamine are mediated through distinct histamine receptors. Mast cells are major producers of histamine, yet effects of histamine on mast cells are currently unclear. The present study shows that histamine induces chemotaxis of mouse mast cells, without affecting mast cell degranulation. Mast cell chemotaxis toward histamine could be blocked by the dual H...

Degranulation of isolated, rat peritoneal mast cells in the presence of low density lipoprotein (LDL) induces cholesteryl ester accumulation in cocultured macrophages with ensuing foam cell formation. This event occurs when the macrophages phagocytose LDL particles that have been bound to the heparin proteoglycans of exocytosed granules. In an attempt to inhibit such foam cell formation pharmac...

Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33 and neurotensin. Mast cells can also...

A panel of rat monoclonal antibodies was used to classify mouse mast cells from four different sources on the basis of their surface determinants. Three populations of mast cells were derived by culturing normal bone marrow, spleen, and peripheral blood cells, whereas the fourth population was isolated directly from the peritoneal cavity. For each population, a surface antigen phenotype was det...

The pathologic mechanisms of chronic obstructive pulmonary disease (COPD) most certainly involves neutrophil granulocytes, cytotoxic T-cells, macophages and mast cells. The aim of this study was to investigate the relation between the number of mast cells in different compartments in bronchial biopsies of central proximal airways to structural changes, lung function tests and emphysema detected...

Mast cells, multifunctional effector cells of the immune system, are implicated in the pathogenesis of hepatic steatosis and fibrosis. Magnesium (Mg) deficiency was reported to increase triglyceride concentration in the liver, and to exacerbate the collagen deposition induced by carbon tetrachloride in the liver. Although Mg deficiency increases mast cells in the small intestine, the kidney and...

The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells th...

The aim of the study was to evaluate the mast cell-blood vessel relationship using double staining CD34/AAS. Sections from 14 cases with lip tumors have been stained with Hematoxylin-Eosin. On additional sections from each case, we highlighted blood vessels by immunohistochemistry for CD34 antigen using the method LSAB2-HRP/DAB, followed by alcian blue-safranin stain for mast cells. We quantifi...

Murine models have highlighted the importance of T-cells and TH2 cytokines in development of allergen-induced airway disease. In contrast, the role of mast cells for the development of allergic airway disease has been controversial. Recent studies in murine models demonstrate a significant contribution of mast cells during the development of airway hyperresponsiveness and airway inflammation. F...