leukotriene-c4 and Food-Hypersensitivity

IgE-dependent basophil activation induced by an allergen elicit the release of LTC4 and the expression of the CD63 membrane marker.. The aim of this study was to check if flow cytometric analysis of basophil activation could be applied to food allergy diagnosis and if this method paralleled LTC4 release.. Patients were selected by the clinical history, skin tests, and provocation tests. Basophil activation induced by food extracts was studied in 24 control subjects and in 27 patients having a food allergy by LTC4 release test (LRT) and by flow cytometric anti-IgE+, CD63 + cell counting (BAT = basophil activation test). In case of negative anti-IgE response a passive blood donor basophil passive sensitization step was added to LRT and BAT. Leucocyte histamine release test was performed in 11 patients.. Basophil activation test was positive in 18/31 cases and LRT in 22/34 cases for food-allergic patients and, respectively, in 1/33 and 1/35 cases for the controls. A correlation was observed between specific IgE, BAT, and LRT. Basophil activation test and LRT performed after passive sensitization had an excellent sensitivity only for specific IgE levels ranging between 3.5 and 35 KU/L.. The present study shows that allergen-induced LTC4 release and anti-IgE, antiCD63 bicolor flow cytometric analysis of basophil activation may be used for food allergy diagnosis. Both tests have a good sensitivity and specificity. Basophil activation test and LRT are more efficient than histamine release test in case of high spontaneous histamine release, frequently observed in case of food allergy.

Topics: Adolescent; Adult; Antibodies, Anti-Idiotypic; Antigens, CD; Basophils; Child; Child, Preschool; Double-Blind Method; Female; Flow Cytometry; Food Hypersensitivity; Histamine Release; Humans; Immunoglobulin E; Leukotriene C4; Male; Methods; Platelet Membrane Glycoproteins; Tetraspanin 30; Time Factors

New cellular tests as flow cytometry and leukotriene release having been set up for allergy diagnosis, we checked the reliability of the LTC4 release test for 4 patients sensitized to wheat flour, oyster and lobster and to anise. Food allergy diagnosis was based on the clinical history, skin tests (pricks and IDR) and specific IgE. After allergen stimulation, LTC4 released was determined by an RIA method using a monoclonal antibody. The allergen extracts used for skin tests and LTC4 release having the same origin, LTC4 release test showed a good correlation with the clinical history whereas specific IgE determinations were less sensitive. Skin tests were negative in the cases.

Topics: Adult; Female; Food Hypersensitivity; Humans; Leukotriene C4; Male; Middle Aged; Occupational Diseases

Mucosal damage is commonly observed in food-sensitive enteropathy in infants, and the generation of leukotrienes is involved in the pathogenesis of this enteropathy. Because supplementing n-3 fatty acids is known to modify the production of leukotrienes, we investigated whether a change of dietary fatty acid composition affects leukotriene synthesis and food hypersensitivity reactions in the intestine by using a mouse model of food-sensitive enteropathy. The model was prepared by feeding ovalbumin to BALB/c mice after intraperitoneal injection of cyclophosphamide. Diets were prepared from soybean oil (control), perilla oil, lard, corn oil, and 0.125 volume of corn oil (low fat diet) and given to mice for 4 wk. Villous heights, crypt depths, leukotriene B4 and C4 production in the intestine were measured. Crypt hyperplasia and villous atrophy were severer in the corn oil-fed group than those of control group, whereas mucosal damage in the perilla oil and low fat diet groups was minimal. In the corn oil-fed group, red blood cell membrane levels of n-3 fatty acids were lower than the control, and the synthesis of leukotrienes was highest among all groups. In the perilla oil and low fat diet groups, n-6 fatty acids were lower than those of control group and leukotriene production was significantly suppressed. These results indicate that reducing cell membrane levels of n-6 fatty acids by feeding less n-6 fatty acids or supplementing n-3 fatty acids, is important to suppress leukotriene biosynthesis for prevention from mucosal damage in food-sensitive enteropathy.

Topics: Animals; Dietary Fats, Unsaturated; Fatty Acids, Omega-6; Fatty Acids, Unsaturated; Female; Food Hypersensitivity; Intestinal Diseases; Intestinal Mucosa; Leukotriene B4; Leukotriene C4; Mice; Mice, Inbred BALB C