Multiple-checkpoint inhibition of thymic stromal lymphopoietin-induced TH2 response by TH17-related cytokines.

BACKGROUND: The interplay between allergy and autoimmunity has been a matter of long debate. Epidemiologic studies point to a decreased frequency of allergy in patients with autoimmune diseases. However, recent studies suggest that IL-17 and related cytokines, which play a central role in autoimmunity, might also promote allergy. OBJECTIVE: To address this controversy, we systematically studied the interactions between T(H)17-related cytokines and the thymic stromal lymphopoietin (TSLP)-mediated proallergic pathway. METHODS: We used human primary dendritic cells (DCs), T cells, and skin explants. A novel geometric representation and multivariate ANOVA were used to analyze the T(H) cytokine profile. RESULTS: We show that IL-17A specifically inhibits TSLP production but increases proinflammatory IL-8 production in human skin explants exposed to TNF-α and IL-4. This inhibitory activity was confirmed in cultured skin explants of atopic dermatitis lesions. At the T-cell level, T(H)17-polarizing cytokines (IL-1ß, IL-6, TGF-ß, and IL-23) inhibited T(H)2 differentiation induced by TSLP-activated DCs. This led to a global dominance of a T(H)17-polarizing environment over TSLP-activated DCs, as revealed by clustering and computational analysis. CONCLUSIONS: Our data indicate that T(H)17-related cytokines are negative regulators of the TSLP immune pathway. This might explain the decreased frequency of allergy in patients with autoimmunity and suggests new means of manipulating proallergic responses.

Fragrance allergy: assessing the safety of washed fabrics.

BACKGROUND: Previously, a quantitative risk assessment suggested there was no risk of induction of fragrance allergy from minor residues of fragrance chemicals on washed fabrics. OBJECTIVE: To investigate whether there was any risk of the elicitation of contact allergy from fragrance chemical residues on fabric in individuals who were already sensitized. METHODS: Thirty-six subjects with a positive patch test to isoeugenol (n = 19) or hydroxyisohexyl 3-cyclohexene carboxaldehyde (n = 17) were recruited. Dose-response and fabric patch tests were performed, respectively, with filter paper and a cotton sample loaded with fragrance in ethanol-diethylphthalate (DEP) and applied in a Finn Chamber or a Hill Top Chamber. RESULTS: Only two subjects reacted to an isoeugenol patch test concentration of 0.01% (>20x the estimated likely skin exposure level), none reacted to lower concentrations. Of 36 subjects, 18 reacted to the fabric patch treated with ethanol-DEP vehicle alone and 20 to the fragrance-chemical-treated fabric patch. These were only minor non-specific skin reactions. They were also quite evenly distributed between the two fragrance chemical allergic groups. CONCLUSIONS: On the basis of the examples studied, fragrance chemical residues present on fabric do not appear to present a risk of the elicitation of immediate or delayed allergic skin reactions on individuals already sensitized.

[Latex allergy]. / Les allergies au latex.

Immediate hypersensitivity to natural rubber latex has increased since the early 1980s. High prevalence of latex sensitization and allergy are observed among healthcare workers, atopic individuals and children who had undergone multiple surgical operations (spina bifida, congenital anomalies). Presenting symptoms are polymorphous: contact urticaria, rhinitis, conjunctivitis, asthma, and anaphylaxis. Corn-starch-latex particles released in the air after powdered gloves manipulation may be inhaled and lead to occupational asthma. The diagnosis may be made by a focused clinical history, prick-test, detection of specific IgE antibody and challenge test. Almost half of patients allergic to natural rubber latex show an associated fruit allergy: avocado, banana, kiwi, chestnut. Most of cutaneous delayed reactions (eczema) to rubber are caused by rubber additives (accelerators of vulcanization, anti-oxidants).

Kawasaki disease in adults: Observations in France and literature review.

OBJECTIVE: Kawasaki disease (KD) is a vasculitis that mostly occurs in young children and rarely in adults. We analyzed the characteristics of adult-onset KD (AKD) in France. METHODS: We collected retrospective and prospective data for patients with a diagnosis of KD occurring after the age of 18 years. Cases were obtained via various French medical networks and identified from the international literature. RESULTS: We included 43 patients of AKD at 26 institution from 1992 to 2015, with mean (SD) age 30 (11) years (range 18-68) and sex ratio (M/F) 1.2; 34 patients met the American Heart Association criteria and 9 were incomplete AKD. The median time to diagnosis was 13 days (interquartile range 8-21). The main symptoms were fever (100%), exanthema (98%), changes in the extremities (91%), conjunctivitis (77%), oral cavity changes (89%), cervical adenitis (55%) and cardiac abnormalities (45%). Overall, 35% of patients showed large-vessel vasculitis: coronary vasculitis (26%) and coronary aneurysm (19%). Treatment was mostly intravenous immunoglobulins (79%) and aspirin (81%). Four patients showed myocardial infarction due to coronary vasculitis, but none were treated with IVIg because of late diagnosis. After a median follow-up of 5 months (range 1-117), persistent aneurysm was noted in 9% of cases. Damage was significantly lower with early treatment than late or no treatment (p=0.01). CONCLUSION: Given the high frequency of cardiac involvement and complications in this series of AKD, diagnosis and treatment should not be delayed, and early IVIg treatment seems to improve the outcome.

Hydrolysed wheat proteins present in cosmetics can induce immediate hypersensitivities.

Cosmetics containing hydrolysed wheat proteins (HWP) can induce rare but severe allergic reactions. 9 patients, all females without common wheat allergy, but with contact urticaria to such cosmetics, were studied. 6 of them also experienced generalized urticaria or anaphylaxis to foods containing HWP. All patients had low to moderate levels of immunoglobulin (Ig)E specific of wheat flour (f4) or gluten (f79). Their sensitivity to HWP and their tolerance to unmodified wheat proteins extracted from grains were confirmed using skin tests. Immunoblotting analyses showed that IgE from all patients reacted with almost all HWP tested. Reactions generally occurred with large random peptide aggregates. IgE reacted also with unmodified grain proteins, which contrasted with skin tests results. They reacted always with salt soluble proteins but variably with gluten proteins. No reaction occurred with gliadins in patients without associated immediate hypersensitivity to food containing HWP. These results show the role of hydrolysis on the allergenicity of wheat proteins, both through skin or digestive routes. At least part of the epitopes involved is pre-existing in unmodified wheat proteins. The aggregation of peptide bearing these epitopes and others created by hydrolysis, along with the increased solubility and the route of exposure, are possible factors of the allergenicity of HWP.