TRPV1+ sensory nerves suppress conjunctival inflammation via SST-SSTR5 signaling in murine allergic conjunctivitis

Allergic conjunctivitis (AC), an allergen-induced ocular inflammatory disease, primarily involves mast cells (MCs) and eosinophils. The role of neuroimmune mechanisms in AC, however, remains to be elucidated. We investigated the effects of transient receptor potential vanilloid 1 (TRPV1)-positive sensory nerve ablation (using resiniferatoxin) and TRPV1 blockade (using Acetamide, N-[4-[[6-[4-(trifluoromethyl)phenyl]-4-pyrimidinyl]oxy]-2-benzothiazolyl] (AMG-517)) on ovalbumin-induced conjunctival allergic inflammation in mice. The results showed an exacerbation of allergic inflammation as evidenced by increased inflammatory gene expression, MC degranulation, tumor necrosis factor-α production by MCs, eosinophil infiltration and activation, and C-C motif chemokine 11 (CCL11) (eotaxin-1) expression in fibroblasts. Subsequent findings demonstrated that TRPV1+ sensory nerves secrete somatostatin (SST), which binds to SST receptor 5 (SSTR5) on MCs and conjunctival fibroblasts. SST effectively inhibited tumor necrosis factor-α production in MCs and CCL11 expression in fibroblasts, thereby reducing eosinophil infiltration and alleviating AC symptoms, including eyelid swelling, lacrimation, conjunctival chemosis, and redness. These findings suggest that targeting TRPV1+ sensory nerve-mediated SST-SSTR5 signaling could be a promising therapeutic strategy for AC, offering insights into neuroimmune mechanisms and potential targeted treatments.

Association between plasma CCL11 (eotaxin-1) and cognitive status in older adults: Differences between rural and urban dwellers

The chemokine CCL11 has been implicated in age-related cognitive deterioration in mice, yet evidence on the relationship between CCL11 and cognitive function in humans is limited. This study explored associations between CCL11 and cognition in rural and urban community-dwelling older adults. Participants were 515 urban dwellers from the 3C-Bordeaux cohort and 318 rural dwellers from the AMI cohort. Plasma CCL11 was measured using an enzyme-linked immunoassay. Mini Mental State Examination (MMSE) test scores were used as the main measure of cognitive performance. Multivariate regression analysis was used to evaluate the cross-sectional association between CCL11 and cognitive performance. CCL11 was significantly higher in rural dwellers compared to city dwellers (median [IQR]: 145 [115-201] pg/mL vs. 103 [85-129] pg/mL; p < 0.001). After adjustment for confounders, CCL11 was found to be negatively associated with cognitive performance in rural dwellers but not in city dwellers. These results suggest that CCL11 may be an independent determinant of cognitive function in older rural dwellers and that the residential environment modifies this association.

Serum biomarkers for allergy in children

A large number of studies investigating various biomarkers for allergy have been published over the past decades. The aim of this review was to evaluate these biomarkers on their diagnostic and/or predictive value. To this date, no single or specific biomarker for allergy has been identified. As allergy is not one disease, but a collection of a number of allergic conditions, it is more plausible a combination of clinical history, clinical readouts, and diagnostic markers will be needed.

Aeroallergen and food IgE sensitization and local and systemic inflammation in asthma

BACKGROUND

We recently reported an independent association between IgE sensitization to food allergens and increased airway inflammation, assessed by fraction of exhaled nitric oxide (FeNO), in a population-based study (J Allergy Clin Immunol, 130, 2012, 397). Similar studies have not been performed in populations with asthma. The aim of the present study was to investigate the allergic sensitization profile in asthmatics and examine FeNO, airway responsiveness and blood eosinophilia in relation to type and degree of IgE sensitization.

METHOD

FeNO, airway responsiveness, blood eosinophil count (B-Eos) and IgE sensitization to food allergens and aeroallergens were determined in 408 subjects with asthma, aged 10-34 years.

RESULTS

Asthmatics had higher prevalence of IgE sensitization against all allergens than controls (P < 0.001). Mite, pollen, furry animal, mould and food sensitizations were each associated with increased FeNO, airway responsiveness and B-Eos in asthmatics. IgE sensitization to mould, furry animals and food allergens was independently related to FeNO (all P < 0.05) after adjustment for age, sex, height, smoking history and medication. IgE sensitization to mould (P < 0.001) and furry animals (P = 0.02) was related to airway responsiveness in a similar model. Finally, IgE sensitization to mould (P = 0.001), furry animals (P < 0.001) and food allergens (P < 0.001) was independently related to B-Eos.

CONCLUSION

Independent effects of IgE sensitization to aeroallergens (furry animals and mould) and food allergens were found on both local and systemic markers of inflammation in asthma. The finding regarding food IgE sensitization is novel, and a clinical implication might be that even food sensitization must be assessed to fully understand inflammation patterns in asthma.

Serum levels of the CC chemokines CCL2, CCL5, and CCL11 in food allergic children with different clinical manifestations

Food allergies (FA) are frequent in 8 % of children under 3 years old and approximately 2 % of adults. Chemokine are involved in various allergies such as FA. The present study was aimed to determine CCL2, CCL5, and CCL11 levels in FA. The study population of this cross-sectional study contained 63 patients suffering from FA and 100 healthy controls. Concentrations of CCL2, CCL5, CCL11, and IgE were measured by enzyme-linked immunosorbent assay (ELISA). Eosinophils were counted using Casy Ι cell counter + analyzer system model SCAREF system GmbH. Differences were considered significant at P < 0.05. Current results showed that FA patients had significantly elevated numbers of circulating periphery eosinophils than the disease-free controls. Serum IgE levels in FA patients were also higher than controls. We also showed that serum levels of CCL2 and CCL11 were significantly enhanced in FA patients compared to control but CCL5 was not detectable. Results of present study revealed that both CCL2 and CCL11 were more elevated in FA children suffering from anaphylaxis and urticaria than bronchial asthma and atopic dermatitis. These results also indicated that more increased levels of CCL2 and CCL11 were observed following consumption of cow's milk and pistachio nuts. Overall, findings of the present study proposed that serum levels of CCL2 and CCL11 are elevated in FA and these may be considered as useful parameters in diagnosis of disorder. It is also possible to design treatments on the basis of blocking of chemokines expression by application of antibodies against them to overcome allergic complications in patients suffering from FA.

Eosinophilic airway inflammation is increased in children with asthma and food allergies

BACKGROUND

Asthma is associated with food allergies in a significant number of children, with evidence linking allergies to asthma severity and morbidity. In this study, we tested our hypothesis that the eosinophilic lower airway inflammation is higher in asthmatic children with food allergies.

AIMS

The aims of the study were to compare the eosinophilic inflammatory markers in asthmatic children with and without food allergies.

MATERIALS AND METHODS

Children with asthma, with (n = 22) and (n = 53) without food allergies were included. All subjects were classified according to the GINA guidelines (2009) and had received at least 3 months of anti-inflammatory therapy prior to testing. Fractional exhaled nitric oxide and sputum differential counts were performed using standard techniques.

RESULTS

  Children with asthma and food allergies had significantly higher fractional exhaled nitric oxide median (range) [(22.4 (6.1-86.9) vs. 10.3 (2.7-38.7) (p = 0.01)] and sputum eosinophil percentage [15.5 (5.0-53.0) vs. 2.0 (0-20) (p < 0.001)] compared with asthmatic children without allergies.

CONCLUSION

These results suggest that the children with asthma and food allergies have increased eosinophilic inflammation of the airways.