OBJECTIVES To determine the synovial mast cell response in early rheumatoid arthritis (RA) during clinical improvement, and to examine for relations with clinical and histological parameters of disease activity. METHODS Twenty two synovial samples were obtained from six patients with RA using needle arthroscopy. The mean disease duration at baseline was eight months, and two to three further ...

Purified rat peritoneal mast cells in vitro die over a period of 2-6 days in conventional serum-containing medium. As mast cells die, they become pyknotic and undergo DNA fragmentation suggestive of an apoptotic process. Treatment of in vitro mast cells with nerve growth factor (NGF) greatly retards and reduces the death of mast cells (EC50 approximately 1 nM), with no effect on mast cell proli...

Background: Leprosy also known as Hansen’s disease (HD), is a chronic infection caused by the Mycobacterium leprae. Mast cells in leprosy have been investigated in the recent past and are being examined as a basis for future studies. Materials and Methods: 119 leprosy cases and 14 control biopsies stained with toluidine blue were assessed for density and distribution of mast cells. 38 cases had...

BACKGROUND Apart from the role of mast cells in maintenance of homeostasis and inflammation, their association with tumors has been described recently. In several malignancies, mast cell density has been found to correlate with angiogenesis, increased risk of metastasis and poor prognosis. AIM The aim of the following study is to compare the number, topography and distribution of mast cells b...

Tendinopathy is often discovered late because the initial development of tendon pathology is asymptomatic. The aim of this study was to examine the potential role of mast cell involvement in early tendinopathy using a high-intensity uphill running (HIUR) exercise model. Twenty-four male Wistar rats were divided in two groups: running group (n = 12); sedentary control group (n = 12). The running...

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...

Increased numbers of mast cells have been reported in explanted human hearts with dilated cardiomyopathy and in animal models of experimentally induced hypertension, myocardial infarction, and chronic volume overload secondary to aortocaval fistula and mitral regurgitation. Accordingly, mast cells have been implicated to have a major role in the pathophysiology of these cardiovascular disorders...

Although their role in the cardiovascular system is still largely unknown, mast cells are present in the myocardium of both experimental animals and humans. Interestingly, cathecolaminergic nerve fibres and mast cells are often described in close morphological and functional interactions in various organs. In the present study we investigated the effects of chronic interference with beta-adrene...

background & aim: according to presence of immune system factors in chronic periapical lesions, hypersensitivity reactions may have some role in pathogenesis of these lesions. up to now, among the factors participating in type i hypersensitivity reaction, only one of them has been studied. so the aim of this study was to evaluate the relationship between the presence of ige & number of mast cel...

ige-mediated cell signaling, induced by cross-linking of high affinity receptor for ige (fcεri) in the presence of antigen (ag), is a well known mechanism described for mast cell activation in allergy and hypersensitivity reactions, which induces a spectrum of cellular responses such as secretion and up-regulation of cell surface fcεri. although for several years  ige  binding  to  fcεri  was  ...