Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a severe IgE-mediated allergic reaction provoked by the combination of wheat-ingestion with intensive physical exercise over the next few hours. Among wheat proteins, -5 gliadin, which is one of the components of fast -gliadin, has been reported as a major allergen in the anaphylaxis. In this study, we detected IgE-binding epitopes within the primary sequence of -5 gliadin using arrays of overlapping peptides synthesized on derivatized cellulose membranes. Sera from four patients with WDEIA having specific IgE to the fast -gliadin were used to probe the membrane. Seven epitopes, QQIPQQQ, QQLPQQQ, QQFPQQQ, QQSPEQQ, QQSPQQQ, QQYPQQQ, and PYPP, were detected within the primary sequence of -5 gliadin. By using sera of 15 patients, 4 of them, QQIPQQQ, QQFPQQQ, QQSPEQQ, and QQSPQQQ, were found to be dominant epitopes. Mutational analysis of the QQIPQQQ and QQFPQQQ indicated that amino acids at positions Gln 1 , Pro 4 , Gln 5 , Gln 6 , and Gln 7 were critical for IgE binding. These results will provide a useful tool for developing safer wheat products in addition to diagnostic and immunotherapy techniques for WDEIA.Food-dependent exercise-induced anaphylaxis is a distinct form of food allergy induced by physical exercise (1). Food items such as shrimp (2), hazelnut (3), buckwheat (4), corn (5), and celery (6) are responsible for the development of food-dependent exercise-induced anaphylaxis. However, of all of the various kinds of food, wheat is reported to be the allergen with the highest frequency in Japan (7). Symptoms are typically generalized urticaria and severe allergic reactions such as shock or hypotension. Because of this serious reaction, it is important to determine the causative food to avoid the allergic reaction. A challenge test consisting of ingestion of the assumed food followed by intense physical exercise is the only reliable method to determine the causative food and to diagnose the disease. However, the challenge test is not always safe because in some cases the test induces an anaphylactic shock. In addition, the most reliable treatment for this disease is to avoid taking the causative food or, alternatively, to take a rest after meals. However, in the case of wheat allergy, elimination causes a decline in the quality of life for the patients. Thus, an in vitro diagnostic method as well as hypoallergenic wheat is necessary for patients with wheat-dependent exercise-induced anaphylaxis (WDEIA). 1Recent studies have revealed the IgE-binding epitopes of several food allergens including egg (8), milk (9, 10), soybean (11), and peanut (12), whereas the IgE-binding epitopes for wheat allergen are controversial. Wheat protein is composed of water/salt-soluble proteins and water/salt-insoluble proteins. Proteins in the water/salt-soluble fraction, such as ␣-amylase inhibitor, peroxidase, glycerinaldehyde-3-phosphate dehydrogenase, serpin, and triosephosphate isomerase, have been considered to be major allergens in patients with bakers' asthma (13-15...

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Inflammation, granulation, and collagen accumulation, which are observed in the wound healing process, occasionally lead to hypertrophic scarring. Several in vitro reports have suggested that skin mast cells (MCs) and their major protease, chymase, participate in the healing process as well as in fibrotic skin diseases. The present study examined the potential involvement of MCs and MC chymase in the healing of burns in mouse dorsal skin. The size of the burn wounds, density of the capillaries, collagen accumulation, MC number, and chymase activity were measured before and 1, 3, 7, and 14 days after burning. The healing process corresponded strongly with MC density and chymase activity in both acute and subacute phases. The maximum decrease in MC number and chymase activity occurred on day 3 when tissue loss due to necrosis was maximal. From day 7 to 14, the burn wounds retracted rapidly accompanied by increases in capillaries and collagen fibers, in correspondence with fast increments in MC numbers and chymase activity at the wound edges. The present results combined with previous in vitro results strongly support the contention that skin MC chymase plays a role in the normal wound healing process, and presumably in dermal fibrotic disorders.

We studied microbicidal activities of reactive nitrogen intermediates (RNI), free fatty acids (FFA), and reactive oxygen intermediates (ROI) against Mycobacterium avium complex (MAC) and the mode of macrophage (mphi) production of these effectors. (1) Intracellular growth of MAC in murine peritoneal mphis was accelerated by scavengers for ROI or RNI and inhibitors of nitric oxide synthase or phospholipase A2, indicating roles of ROI, RNI, and FFA in mphi anti-MAC functions. (2) Acidified NaNO2-derived RNI, FFA (linolenic and arachidonic acids), and the H2O2-mediated halogenation system exhibited a significant anti-MAC bactericidal activity. The combination of RNI with FFA showed a synergistic effect. However, the H2O2-halogenation system in combination with either RNI or FFA showed an antagonism. When Listeria monocytogenes (Lm) was used as a target organism, the combinations of RNI + FFA and RNI + H2O2-halogenation gave a synergistic effect, whereas FFA + H2O2-halogenation showed an antagonism in exerting bactericidal activity. In addition, when ROI generated by the xanthine oxidase-acetaldehyde system was combined with RNI, anti-Lm but not anti-MAC activity was potentiated. (3) ROI production by murine peritoneal mphis was observed immediately after contact with MAC organisms (MAC stimulation) and ceased within 2 h. FFA release was seen 1-24 h after MAC stimulation. RNI production was initiated from 3 h and increased during the first 36 h and continued at least for 4 days. These findings suggest that RNI and FFA rather than ROI are important effectors of anti-MAC functions of mphis, and the collaborating action of RNI with FFA temporarily participates in mphi-mediated killing of MAC in the relatively early phase after MAC stimulation.