The roles of mast cells in allergic inflammation and mast cell-related disorders

Mast cells, which are major effector cells in allergic reactions, are found in the perivascular spaces of most tissues and contain pro-inflammatory and vasoactive mediators. These mediators are released after IgE receptor cross-linking induced by allergens or other stimuli, including anaphylatoxins (C3a and C5a), aggregated IgG, certain drugs, venoms, and physical stimuli (pressure and temperature changes), as well as cytokines and neuropeptides. The excess release of these mediators can cause variable allergic symptoms and signs, such as bronchospasm, itching, flushing, nausea, vomiting, diarrhea, abdominal pain, vascular instability, and anaphylaxis. Furthermore, mast cell disorders may involve either excessive proliferation of mast cells or abnormal mast cell reactivity. Mast cell disorders can be broadly divided into 3 types: primary, secondary, and idiopathic. All of these disorders present with signs and symptoms of mast cell activation and differ in severity and involvement of various organ systems. The best characterized primary disorder is mastocytosis. Systemic and cutaneous forms of the disease are well described. Secondary disorders include typical allergic diseases and some types of urticarial diseases. In this article, the biochemical characteristics of mast cells and the role of mast cells in allergic inflammation, as well as the classification, diagnosis, and management of mast cell-related disorders, will be reviewed.

Expression of Complement C3a Receptor and C5a Receptor by A(beta)(1-42) Stimulated Human Neuroblastoma Cell Line

BACKGROUND: Complementary receptors have been suggested to play causative roles in the neuroinflammatory process of Alzheimer's disease (AD). The genetic expressions of the C3a receptor (C3aR), C5a receptor (C5aR) and the protein expressions of the C3aR and C5aR were examined in the human neuroblastoma cell line, SK-N-SH, after the administration of amyloid peptide (A1-42). METHODS: SK-N-SH cells were incubated overnight with a single dose of 20 M of aggregated A (A1-42). An inhibition study was done with actinomycin D (ActD, 2.5 M) or with the administration of cycloheximide (CHX, 2.5 M) to the cell suspension. Messenger RNA expressions of C3aR and C5aR were detected by RT-PCR. The intensity of bands from 6% polyacrylamide electrophoretic gel was analyzed by a bioimage analyzer. The protein production of C3aR and C5aR in the A-treated cells was also measured by flow cytometry. NFB activation after treatment of A in the cells was detected by an electrophoretic mobility-shift assay. RESULTS: A1-42 increased the expression of C3aR and C5aR. ActD inhibited the expression of both anaphylatoxin receptors but CHX only suppressed C5aR mRNA expression. Activated NFB was demonstrated in the A-stimulated cells. CONCLUSIONS: C3aR and C5aR were constitutively expressed in the human neuroblastoma SK-N-SH cell. Expression of these anaphylatoxin receptors was upregulated after A1-42 stimulation, which as a result, may contribute to the complement-mediated neuroinflammation of AD.

Efficacies of the Modified Ultrafiltration and Peritoneal Dialysis in Removing Inflammatory Mediators After Pediatric Cardiac Surgery / 대한흉부외과학회지

BACKGROUND: Cardiopulmonary bypass induces an acute systemic inflammatory response mediated by complement activation and cytokine release. This response is likely to cause capillary leak syndrome and organ dysfunction in infants. Removing harmful cytokines and complement anaphylatoxins after cardiopulmonary bypass may attenuate this response. This study was conducted to see if the modified ultrafiltration and postoperative peritoneal dialysis can reduce plasma inflammatory mediators in pediatric cardiac surgery. MATERIAL AND METHOD: 30 infants (age 1.1 to 12.6 months) who underwent closures of ventricular septal defect using cardiopulmonary bypass (CPB) were enrolled in this study. These patients were divided into three groups; 10 patients selected randomly underwent modified ultrafiltration (Group U), 10 with small body weights (

Bidder's organ extract induced anaphylaxis in experimental animals.

Bidder's organ (BO, a vestigeal organ), present in toad Bufo melanostictus (Schenider), is a characteristic feature of all male bufo. Its possible anaphylactic properties are investigated on experimental animals. BO extract produced both in vivo and in vitro anaphylactic reaction in guineapig. Dyspnoea and bronchoconstriction was a major cause of anaphylactic death. Blood histamine level was significantly increased in the anaphylactic animals. BO extract significantly released histamine from chopped lung preparation, an action antagonised by disodium chromoglycate. BO extract degranulated peritoneal mast cell in vitro. Passive cutaneous anaphylactic reactions were enhanced by BO extract and were significantly inhibited by disodium chromoglycate. Anaphylotoxin (identity not known) present in bidder's organ is probably involved in toad defence.

Generation of inflammatory cytokines and anaphylatoxins in whole blood under normal blood banking condition / 대한수혈학회지

BACKGROUND: Several recent studies have reported that generation of inflammatory cytokines and activation of complements may be associated with febrile nonhemolytic transfusion reactions (FNHTR). However, few data are available for whole blood, which is still commonly utilized for massive transfusion and for autologous transfusion. METHODS: A total of 15 whole blood units from healthy adult donors was collected and stored at 4degrees C for 35 days. During the storage time, samples for analyses of cytokines including interleukin-1alpha (IL-1alpha), IL-2, IL-6, IL-8, and tumor necrosis factor alpha (TNFalpha) and anaphylatoxins such as C3a and C5a were obtained on day 0, 1, 3, 5, 7, 14, 28, and 35. Cytokines were measured by enzyme-linked immunosorbent assay and anaphylatoxins by radioimmunoassay. RESULTS: IL-1alpha (<0.5 pg/mL), IL-2 (<7 pg/mL), and TNFalpha (<4.4 pg/mL) were not detectable. IL-6 was measured in 4 units with low level (1.1-4.0 pg/mL) and IL-8 showed slightly higher level (10.5 pg/mL) on day 35. Anaphylatoxins (C3a and C5a) were detectable at the level of 1350.0 ng/mL on day 21 and of 14.6 ng/mL on day 14, respectively, which were significantly increased levels compared with those on day 0. The levels of C3a and C5a reached 2513.3 ng/mL and 18.4 ng/mL on day 35, respectively. CONCLUSIONS: It is not likely that cytokines generated during storage of whole blood under normal blood banking condition could explain FNHTR. However, anaphylatoxins are elevated in whole blood after 2 weeks of storage, which might be due to complement activation by the plastic surface of blood bag.