The Skin

Sargassum hemiphyllum inhibits atopic allergic reaction via the regulation of inflammatory mediators

Sargassum hemiphyllum (SH) has long been used in Korean folk medicine for the therapeutic treatment of various allergic diseases. The effects of SH in previous experimental models, however, have been inconclusive. We studied the effects of methanol extract of SH on mast cells. Our experiments showed that SH significantly inhibited compound 48/80-induced histamine and beta-hexosaminidase release from rat peritoneal mast cells. SH inhibited interleukin (IL)-8 and tumor necrosis factor (TNF)-alpha release induced by phorbol 12-myristate 13-acetate and A23187 from HMC-1, and it also showed an inhibitory effect on the anti-dinitrophenyl IgE antibody-induced passive cutaneous anaphylaxis reaction. In addition, SH inhibited the increase of TNF-alpha-induced NF-kappaB protein levels, transcription factor of TNF-alpha from 293T cells. A period of 48 h exposure to SH had little effect on HMC-1 cell viability. Our results suggest that SH has an inhibitory effect on the atopic allergic reaction and thus this may be useful in the treatment of allergic inflammatory diseases, such as atopic dermatitis.

[Food allergens in children]

Food hypersensitivity is increasing, with clinical indications and allergens multiplying and evolving. We report our experience with clinical indications and distribution of allergens in children with food hypersensitivity. Data were established in a prospective study at medical centres in Nancy and Toulouse (France). We studied 378 children with food hypersensitivity indicated by food challenge, which account for 74.2% of food hypersensitivity. Clinical features were: atopic dermatitis (46.5%), urticaria (17.9%), oedema (14.2%), asthma (8.4%), anaphylaxis (5.2%), gastro-intestinal symptoms (2.1%), oral syndrome (1.8%) and rhino-conjunctivitis (0.5%). Five allergens accounted for 82% of confirmed food hypersensitivity: egg (51.8%), peanut (34.3%), milk (11.6%), mustard (8.9%) and codfish (7.1%). Allergens according to the symptoms showed that peanut allergies were more serious than other food allergy. Allergens according to age showed that peanut allergy is the first food allergy occurring after the age of three. There exists a modification in children's allergen distribution. Peanut allergy is increasing seriously, and diagnosis with food challenge is a necessity.

The mucosal adhesion receptor alpha4beta7 integrin is selectively increased in lymphocytes stimulated with beta-lactoglobulin in children allergic to cow's milk

BACKGROUND

It has been shown in mice that the integrin alpha4beta7 directs the migration of memory T cells into the gut-associated lymphoid tissue. However, little is known about T-cell homing mechanisms in children with food allergies.

OBJECTIVE

We investigated the expression of this and other integrins in children with different manifestations of cow's milk allergy (urticaria, atopic dermatitis, and wheezing).

METHODS

PBMCs were stimulated with beta-lactoglobulin, 1 of the major allergenic proteins in cow's milk, and tetanus toxoid. Integrin expression was studied by flow cytometric analysis after 1 week of culture.

RESULTS

We found significantly higher expression of the alpha4beta7 integrin in cells from patients compared with control subjects with no allergies (P =. 005) when beta-lactoglobulin was used to stimulate the cells. alpha4beta7 integrin was also expressed at significantly higher levels in beta-lactoglobulin-stimulated cells than in tetanus toxoid-stimulated cells (P =.005). The alphaEbeta7 and the alpha4beta1 integrins were not upregulated by allergen stimulation. Most alpha4beta7 integrin-expressing cells were identified as CD4(+) T cells.

CONCLUSION

These results show that alpha4beta7 integrin expression after stimulation with beta-lactoglobulin correlates with the presumptive site of cow's milk sensitization (ie, the gut-associated lymphoid tissue but not with the site of symptoms of cow's milk allergy).