Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunopathological studies of SIDS share the problems of all necropsy based studies of this syndrome: the extent of autolytic changes in the material under study; and the lack of appropriate controls. Despite these problems, several studies have been performed on serum, bronchoalveolar lavage, and pulmonary tissue. Many of these studies have been inspired by the modified anaphylaxis hypothesis, based on the experiments of Coombs and coworkers. Lightly anaesthetised guinea-pigs, which had been sensitised to cows' milk protein, were shown to die after intratracheal challenge. Studies of serum IgE concentrations in SIDS initially indicated raised specific IgE for Dermatophagoides pteronyssinus, Aspergillus fumigatus, and bovine beta-lactoglobulin, but subsequent studies have not sustained these findings. Raised immunoglobulin concentrations in bronchoalveolar lavage fluid have been found in association with SIDS but this probably reflects plasma leakage rather than local secretion. Immunocytochemical analysis of lavage cells performed by the same group revealed no major difference between SIDS cases and controls, although these were limited to four cases. To date, there have been no comprehensive studies of the inflammatory cell content of the pulmonary parenchyma in SIDS. In our own studies, we have examined the mast cell and eosinophil populations in the lungs of 49 cases of infants with SIDS and in 33 infants dying of non-pulmonary causes in the first 18 months of life. We found no difference in mast cell numbers between the groups but there was a striking excess of eosinophils in the lungs of infants dying of SIDS. Because eosinophils can secrete oxygen free radicals and cytotoxic cationic proteins, we regard this as evidence of a potential mechanism for the pulmonary oedema that is characteristic of SIDS. A viral infection which might otherwise have been trivial could therefore prove fatal.
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PMID:Immunopathology of SIDS. 147 58

Bronchopulmonary dysplasia (BPD), the most common cause of chronic lung disease in prematurely born infants, is histologically characterized by various degrees of airway and alveolar septal fibrosis. Tryptase, a serine protease specific to mast cells, has been shown to have potent fibroblast mitogenic properties and in addition has been shown to be increased in adult fibrotic lung disorders. Based on this analogy, the distribution of pulmonary mast cells exhibiting tryptase immunoreactivity was investigated by immunoperoxidase staining in autopsy specimens of infants dying with BPD. Morphologically normal lung specimens from similarly aged infants dying of sudden infant death syndrome (SIDS) served as controls. Tryptase-positive mast cell counts were performed at 250x from at least 10 random fields in bronchial, peribronchiolar, and alveolar regions. Compared to controls, in lung sections exhibiting typical histologic features of long-standing BPD, tryptase positive cells were significantly increased in bronchial (23.9 +/- 3.6 vs 14.4 +/- 2.3) and peribronchiolar (15.3 +/- 3.2 vs 4.63 +/- 0.6) regions compared to controls (P < 0.05, Student's t test). In particular, alveolar regions exhibiting moderate to severe degrees of septal fibrosis exhibited a dramatic increase in the number of tryptase-positive cells (9.83 +/- 1.89 vs 0.34 +/- 0.18, P = 0.003). These findings of a tryptase-positive mast cell hyperplasia in BPD suggest potential roles of mast cells as well as tryptase in the pathogenesis of this disease.
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PMID:Tryptase immunoreactive mast cell hyperplasia in bronchopulmonary dysplasia. 756 12

A series of cases of sudden unexpected post-neonatal deaths from two centres in the UK have been investigated for evidence of mast cell activation using the biochemical markers tryptase and 9 alpha,11 beta-PGF2. Tryptase was selected as a possible marker because it is a component of mast cell secretory granules and, unlike histamine, it is not released from basophils. The prostaglandin 9 alpha,11 beta-PGF2 is an initial and pharmacologically active metabolite of PGD2, the major mast cell-derived cyclooxygenase product. This prostaglandin was chosen to serve as a marker of newly generated mediator release. In the study, unexplained infant deaths were associated with a higher concentration of tryptase in serum compared with cases of unexpected, but subsequently explained death. However, 9 alpha,11 beta-PGF2 was found to be an unsuitable post mortem marker in this situation. These results provide direct evidence that mast cell degranulation, possibly as a result of anaphylaxis, may be occurring around the time of death in some cases of cot death.
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PMID:The anaphylaxis hypothesis of sudden infant death syndrome (SIDS): mast cell degranulation in cot death revealed by elevated concentrations of tryptase in serum. 788 24

The pathogenesis of sudden infant death syndrome (SIDS) is elusive and probably multifactorial. The occurrence of mast cell activation in SIDS was assessed in this study by measuring concentrations of tryptase, a neutral protease produced mainly by mast cells, in postmortem sera from term infants with SIDS and from age-matched control infants who died unexpectedly at home from a known cause. Tryptase levels were significantly higher in the 50 infants with SIDS than in the 15 control infants (p = 0.0004). Forty percent of the infants with SIDS and none of the control infants had a tryptase level greater than 10 ng/ml, the threshold chosen to indicate premortem mast cell activation. An infant with SIDS had a 20-fold higher chance of having an elevated tryptase level compared with a control infant. The postmortem interval did not influence these results. Thus mast cell-mediated anaphylaxis is likely to be the pathogenetic mechanism involved in some but not all SIDS cases. Recognition of this pathway as operative in SIDS should facilitate a more precise identification of the allergens involved, the processes leading to mast cell activation, and procedures to identify those infants at risk for anaphylaxis, and should, in time, lead to better therapeutic interventions aimed at preventing this specific cause of SIDS.
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PMID:Involvement of mast cells in sudden infant death syndrome. 806 77

A recent immunohistochemical study found increased numbers of eosinophils, but no mast cells, in the pulmonary parenchyma of infants who died of sudden infant death syndrome (SIDS). The present study tested the hypothesis that this pulmonary eosinophilia could be IgE-mediated. Histomorphometry was used to compare the numbers of eosinophils, mast cells, and IgG-, IgA-, IgM- and IgE-expressing lymphoid cells in the lungs of two groups of infants. Twenty-eight subjects aged less than 1 year were selected from post-mortem records of infant deaths between 1989 and 1992. Fourteen were cases of SIDS and these infants were matched for age and gender to 14 controls who died of other non-pulmonary conditions. Immunohistochemical stains were used and positive cells were counted on six peribronchial and six subpleural fields. The numbers of eosinophils in both peribronchial and subpleural regions were significantly higher in SIDS compared with controls (P = 0.0071 and P = 0.041, respectively). The numbers of IgA-expressing lymphoid cells were also significantly increased in SIDS cases (P = 0.042). There were no differences in IgG, IgM or IgE expression or in mast cell numbers. These results confirmed that pulmonary eosinophils are increased in SIDS, but not through an IgE-mediated pathway.
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PMID:Pulmonary eosinophilia in sudden infant death syndrome. 856 97

Mast cells were found in 24 cases of 65 studied choroid plexuses in children aged from 1 day to 7 years. In 16 observations mast cells degranulation was noted. Mast cell degranulation was established to correlate with acute infectious diseases with CNS involvement. Degranulating mast cell presence in choroid plexus in children who died from sudden infant death syndrome supports the evidence indicating the essential role of mast cell activation in this disease.
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PMID:[Mast cells in the choroid plexus of the hindbrain in children]. 946 Jun 79