T-cell signal transduction in children with cow's milk allergy -- increased MAP kinase activation in patients with acute symptoms of cow's milk allergy.

The precise immune mechanisms behind cow's milk allergy (CMA) are still unknown. Previously, the production of the cytokines TNF-alpha and IFN-gamma in T cells from children with CMA has been shown to be decreased, and the production of IL-4 has been shown to be increased when compared to healthy children. As these aberrations in cytokine production may be associated with disturbances in cellular function, we investigated whether T-cell signal transduction is abnormal in children with CMA. For this purpose we evaluated the activation of the MAP kinase Erk2. Thirty-nine infants were included in the study. Of those with CMA, 13 had acute symptoms and 9 were free of symptoms due to a successful elimination diet at the time of the study. To activate T cells and to stimulate MAP kinase phosphorylation, peripheral blood mononuclear cells (PBMC) were incubated with Concanavalin A (ConA). The change in MAP kinase phosphorylation was measured by Western blotting. The increase in MAP kinase phosphorylation after stimulation with ConA for 5 min was significantly higher in cells from patients with acute symptoms of CMA than in cells from CMA patients free of symptoms or cells from healthy children. A time-course experiment showed that the change in MAP kinase phosphorylation was still increasing after 10 min incubation in cells from patients with acute symptoms of CMA. The increased MAP kinase activation was found to correlate positively with non-IgE mediated CMA in patients with acute symptoms of CMA.

Cholesterol precursors and plant sterols in children with food allergy.

BACKGROUND: The data on lipid metabolism in allergic children is limited. OBJECTIVE: We investigated lipid and sterol metabolism in young children whose diets were restricted because of food allergy. DESIGN: Children in group A [n = 21; mean (+/- SD) age: 1.78 +/- 0.73 y] were allergic to fish, eggs, and either cow milk or cereals; those in group B (n = 31, aged 1.45 +/- 0.58 y) were allergic to fish, eggs, and both cow milk and cereals. Cholesterol precursor and plant sterol to cholesterol ratios (10(2) x micro mol/mmol cholesterol) and apolipoprotein E phenotype distributions were analyzed in 36 subjects. The control group for cholesterol precursor and plant sterol measurements consisted of 18 healthy age-matched children. RESULTS: The mean serum cholesterol concentration was 3.6 +/- 0.6 mmol/L, and HDL cholesterol was 1.03 +/- 0.3 mmol/L in group A. Corresponding values in group B were 3.4 +/- 0.7 and 1.09 +/- 0.2 mmol/L. The daily cholesterol intake was low: 61.3 +/- 36.0 mg in group A and 50.7 +/- 48.5 mg in group B. Cholesterol precursor plant sterol concentrations were significantly higher in allergic subjects than in control subjects. CONCLUSIONS: Allergic children with restricted diets have a low intake of cholesterol and relatively low serum cholesterol concentrations. Dietary intake of plant sterols was obviously increased because of supplementation with rapeseed oil, which is rich in plant sterols, leading to elevated plant sterol concentrations. Plant sterols may have inhibited cholesterol absorption, which in turn stimulated cholesterol synthesis in compensation, also explaining the increased precursor sterol ratios in serum in our subjects.

Low frequency of CD4+, but not CD8+, T cells expressing interferon-gamma is related to cow's milk allergy in infancy.

Low interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) production in peripheral blood mononuclear cells (PBMC) from patients with atopic dermatitis and food allergy have been reported previously. However, it remains unclear whether the weak cytokine production is caused by the imbalance of specific T-cell subsets or by dysregulation of T-cell function. In the present study we investigated the intracellular expression of these cytokines at a single-cell level to clarify the background of the disruption. Twelve of 27 breast-fed infants (0.1-8.8 months of age) had challenge-proven cow's milk allergy (CMA), and 15 infants were studied as a healthy control group. PBMC were stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin. The frequencies of the cells expressing intracellular IL-4, IFN-gamma, and TNF-alpha were assessed using flow cytometry. In addition, at this time-point leucocyte subsets from the milk of mothers of these infants were evaluated using light microscopy. A lower number of CD8+ T cells and the defective capability of CD4+ T cells to express IFN-gamma in infant's peripheral blood co-existed with a lower number of macrophages in their mother's milk.

Leucocytes in human milk and lymphocyte subsets in cow's milk-allergic infants.

The breast-fed infant ingests an average of 108 leucocytes per day, with breast-feeding often continuing for several months. The precise role of human milk leucocytes is still unresolved. Breast-feeding has been recommended for infants at high risk of allergy to prevent or delay the development of food allergies and atopic eczema. However, studies dealing with distinct immunologic factors in the mother's milk, and their effect on health status or development of allergies in the infant, are scarce. We evaluated the relationship between the cellular composition of human milk and the development of cow's milk allergy (CMA) in the breast-fed infant. Leucocyte subsets in the breast-fed infants were also measured. The study population comprised 61 breast-feeding mothers and their infants. Thirty-nine mothers each had a cow's milk-allergic infant, 10 had an infant with atopic dermatitis without CMA, and 12 mothers had a healthy infant. Leucocyte subsets in mothers' milk were counted using a light microscope and confirmed by flow cytometry. In infants, peripheral blood lymphocyte subsets were determined by flow cytometry and were correlated with the health status of the breast-fed infant and leucocyte composition of the mother's milk. Human milk was found to be a non-homogenous morphological entity. In the milk of mothers of infants with CMA, the proportion of macrophages was significantly smaller than in the mothers with infants without CMA (p = 0.036, t-test). Mothers with high proportions of neutrophils in their milk (> 20%) had significantly more often infants with CMA than did those with low proportions of neutrophils (p = 0.02; Fischer's exact test). Eosinophils comprising > 1% of milk cells were only detected in the mothers who had infants with CMA. Furthermore, the proportions of CD4+ T cells were positively correlated with the proportion of milk macrophages and negatively with the percentage of milk neutrophils and eosinophils. The proportions of total B cells and those expressing CD23, a low-affinity immunoglobulin E (IgE) receptor, were positively correlated with the proportions of neutrophils and eosinophils in mother's milk and negatively with the percentage of milk macrophages. To conclude, the composition of breast milk in some mothers is abnormal and correlates with a diagnosis of CMA in a breast-fed infant. This may provide a new and interesting insight into the development of food allergies.

[Expression of interleukin-4, interferon-gamma and lymphocyte surface markers in small intestinal mucosa of adult patients with cereal allergy]. / Interleukin-4, interferon-gamma és lymphocyta sejtfelszíni markerek vizsgálata gabonaallergiás felnóttek vékonybél-nyálkahártyájában.

INTRODUCTION: The mechanism for adverse reactions to foods in the gastrointestinal tract are poorly understood. Previous studies of other atopic diseases and animal models suggest that lymphocytes and cytokines may be implicated in the pathogenesis of food allergy. AIM: The authors investigated the expression of interleukin-4, interferon-gamma and other lymphocyte markers of patients with cereal allergy (wheat, rye, oats) and of controls. PATIENTS/METHOD: Expressions of cytokines and lymphocyte markers on duodenal mucosa of nine patients (mean age 38.3 years, range 18-50 years, 8 women and one man) and nine controls (mean age 36 years, range 24-54 years, 6 women, 3 men) by means of immunohistochemistry were investigated. RESULTS: The mucosal structure on every biopsy specimens was normal. Despite the normal structure the expression of Ki-67 intranuclear proliferation marker was higher in patients with cereal allergy. Expression of interleukin-4 was markedly elevated in the food allergy group, however, interferon-gamma density showed no inter-group difference. The densities of CD4 (1251 vs. 1053 cells/mm2) and HLA-DR positive cells (1227 vs. 1064 cells/mm2) in the lamina propria of cereal allergy group were significantly elevated when compared with controls (P = 0.05 and P = 0.04, respectively). The densities of CD3, CD8, TCR alpha/beta and gamma/delta, HLA-DP, IgA, IgA1, IgA2-containing cells did not differ in the two groups studied. CONCLUSIONS: The authors results suggest that, despite the normal mucosal structure, the increased expression of CD4 and HLA-DR positive cells show a sign of inflammation in duodenal biopsies of patients with cereal allergy. Moreover, increased density of IL-4 may suggest its role in the pathogenesis of cereal hypersensitivity.

A novel mutation in the third extracellular domain of the tumor necrosis factor receptor 1 in a Finnish family with autosomal-dominant recurrent fever.

OBJECTIVE: To investigate the presence of TRAPS (tumor necrosis factor receptor-associated periodic syndrome), which is a recently defined, dominantly inherited autoinflammatory syndrome caused by mutations in the tumor necrosis factor receptor superfamily 1A gene (TNFRSF1A, CD120a), in a Finnish family with recurrent fever. METHODS: The TNFRSF1A gene was sequenced in both affected and unaffected family members. Flow cytometry and enzyme-linked immunosorbent assay analyses were used to assess membrane expression and serum levels of the TNFRSF1A protein, respectively. RESULTS: A missense mutation in exon 4, located in the third extracellular domain of TNFRSF1A and resulting in an amino acid substitution (F112I) close to a conserved cysteine, was found in all 4 affected family members and in 1 asymptomatic individual. The mutation was clearly associated with low levels of soluble TNFRSF1A as well as with the clinical symptoms of recurrent fever and abdominal pain. Impaired shedding of TNFRSF1A after phorbol myristate acetate stimulation was detected in blood granulocytes and monocytes from the 3 adult family members with the mutation, but in the child bearing the mutation and showing clinical symptoms of recent onset, the shedding defect was less marked. CONCLUSION: TRAPS should be suspected in any patient who presents with a history of intermittent fever accompanied by unexplained abdominal pain, arthritis, or skin rash, particularly in the presence of a family history of such symptoms. Screening for low serum levels of soluble TNFRSF1A identifies individuals who are likely to have TNFRSF1A mutations.