Tissue inhibitors of matrix metalloproteinase-1 levels are increased in serum of patients with allergic contact dermatitis

Inflammatory plasma signature of chronic hand eczema: Associations with aetiological and clinical subtypes

BACKGROUND

Chronic hand eczema (CHE) is a highly prevalent, heterogeneous, skin disease that encompasses different aetiological and clinical subtypes. Severe CHE without atopic dermatitis has been associated with systemic inflammation; yet it remains unknown if specific CHE subtypes leave distinct, systemic, molecular signatures.

OBJECTIVES

To characterize the inflammatory plasma signature of different aetiological and clinical CHE subtypes.

METHODS

We assessed expression levels of 266 inflammatory and cardiovascular disease risk plasma proteins as well as filaggrin gene mutation status in 51 well-characterized CHE patients without concomitant atopic dermatitis and 40 healthy controls. Plasma protein expression was compared between aetiological and clinical CHE subgroups and controls both overall and according to clinical CHE severity. Correlation analyses for biomarkers, clinical and self-reported variables were performed.

RESULTS

Very severe, chronic allergic contact dermatitis (ACD) on the hands was associated with a mixed Type 1/Type 2 systemic immune activation as compared with controls. Circulating levels of Type 1/Type 2 inflammatory biomarkers correlated positively with clinical disease severity among CHE patients with ACD. No biomarkers were found, that could discriminate between aetiological subtypes, for example, between ACD and irritant contact dermatitis. Hyperkeratotic CHE showed a distinct, non-atopic dermatitis-like, systemic footprint with upregulation of markers associated with Type 1 inflammation and tumour necrosis factor alpha, but not Type 2 inflammation. Increased levels of CCL19 and CXCL9/10 could discriminate hyperkeratotic CHE from both vesicular and chronic fissured CHE, whereas no difference was found between the latter two subtypes.

CONCLUSION

Profiling of systemic biomarkers showed potential for identifying certain CHE subtypes. Peripheral blood levels of inflammatory biomarkers were associated and correlated with the clinical disease severity of chronic ACD on the hands, underlining that this is a systemic disease. We question whether hyperkeratotic CHE should be classified as eczema.

Predicting persistence of atopic dermatitis in children using clinical attributes and serum proteins

BACKGROUND

Atopic dermatitis (AD) is the most common inflammatory skin disease in children, with 30% of all those diagnosed developing chronic or relapsing disease by adolescence. Such disease persistence cannot yet be predicted. The aim of the present study was to predict the natural course of AD using clinical parameters and serum proteins.

METHODS

Sera of 144 children with AD (age 0-3 years) were analyzed for IgE and 33 cytokines, chemokines, and growth factors. Patient disease course until the age of 7 years was assessed retrospectively. Unsupervised k-means clustering was performed to define disease endotypes. Identified factors associated with AD persistence at the age of 7 years were validated in children with AD in an independent cohort (LISA Munich; n = 168). Logistic regression and XGBoosting methods followed by cross-validation were applied to predict individual disease outcomes.

RESULTS

Three distinct endotypes were found in infancy, characterized by a unique inflammatory signature. Factors associated with disease persistence were disease score (SCORAD), involvement of the limbs, flexural lesion distribution at the age of 3 years, allergic comorbidities, and disease exacerbation by the trigger factors stress, pollen exposure, and change in weather. Persistence was predicted with a sensitivity of 81.8% and a specificity of 82.4%. Factors with a high impact on the prediction of persistence were SCORAD at the age of 3 years, trigger factors, and low VEGF serum levels.

CONCLUSION

Atopic dermatitis in infancy comprises three immunological endotypes. Disease persistence can be predicted using serum cytokines and clinical variables.

Serum osteopontin levels in disseminated allergic contact dermatitis

PURPOSE

The aim of the study was to evaluate serum osteopontin (OPN) concentrations in patients with disseminated form of allergic contact dermatitis (ACD), and to assess the relationship between serum OPN level and disease severity.

PATIENTS AND METHODS

Twenty-four patients with numerous allergic contact dermatitis lesions and twenty-two age- and sex-matched healthy subjects as a control group were enrolled in the study. Serum osteopontin levels were measured in the ACD patients twice: in the acute stage and during disease remission by ELISA.

RESULTS

Serum OPN concentrations were significantly increased in patients with disseminated ACD examined in the acute stage as compared to healthy subjects and ACD patients during remission (p<0.01 and p<0.001, respectively). In the ACD patients with extensive skin lesions (EASI>10), OPN serum levels were significantly higher than in those with mild disease (EASI<10).

CONCLUSIONS

Acute disseminated ACD is characterized by elevated serum concentrations of osteopontin, with levels depending on ACD severity, which indicates its role in the elicitation phase of allergic contact dermatitis. The possibility of inhibition of OPN activity may create a new therapeutic perspective in severe forms of this troublesome skin disease.

Mesenteric lymph node transcriptome profiles in BALB/c mice sensitized to three common food allergens

Background

Food allergy is a serious health concern among infants and young children. Although immunological mechanism of food allergy is well documented, the molecular mechanism(s) involved in food allergen sensitization have not been well characterized. Therefore, the present study analyzed the mesenteric lymph node (MLN) transcriptome profiles of BALB/c mice in response to three common food allergens.

Results

Microarray analysis identified a total of 1361, 533 and 488 differentially expressed genes in response to β-lactoglobulin (BLG) from cow's milk, ovalbumin (OVA) from hen's egg white and peanut agglutinin (PNA) sensitizations, respectively (p < 0.05). A total of 150 genes were commonly expressed in all antigen sensitized groups. The expression of seven representative genes from microarray experiment was validated by real-time RT-PCR. All allergens induced significant ear swelling and serum IgG1 concentrations, whereas IgE concentrations were increased in BLG- and PNA-treated mice (p < 0.05). Treatment with OVA and PNA significantly induced plasma histamine concentrations (p < 0.05). The PCA demonstrated the presence of allergen-specific IgE in the serum of previously sensitized and challenged mice.

Conclusions

Immunological profiles indicate that the allergen dosages used are sufficient to sensitize the BALB/c mice and to conduct transcriptome profiling. Microarray studies identified several differentially expressed genes in the sensitization phase of the food allergy. These findings will help to better understand the underlying molecular mechanism(s) of food allergen sensitizations and may be useful in identifying the potential biomarkers of food allergy.

Regulation of soluble vascular endothelial growth factor receptor 1 secretion from human endothelial cells by tissue inhibitor of metalloproteinase 1

Vascular endothelial growth factor (VEGF) and its soluble receptor (sVEGFR-1) are key regulators in human ovarian angiogenesis. Produced by granulosa and ovarian theca interna cells, VEGF promotes blood vessel growth during follicular development and corpus luteum formation, whereas sVEGFR-1, which is secreted by endothelial cells, functions as an antagonist to VEGF activity by binding it. In order to gain further insights into the regulatory mechanisms of ovarian angiogenesis, the aim of the present study was to analyze the influence of tissue inhibitor of metalloproteinase 1 (TIMP-1), which is actively involved in the degradation and remodeling of the extracellular matrix, on sVEGFR-1 secretion of cultured human umbilical vein endothelial cells. sVEGFR-1 production was determined in the culture supernatant by Sandwich-ELISA. We showed that TIMP-1 produced by human granulosa cells and recombinant human TIMP-1 both significantly increased the production of sVEGFR-1 in endothelial cells. Also, the down-regulation of TIMP-1 expression by RNA interference resulted in a significant reduction of endothelial sVEGFR-1 secretion into the culture medium. Furthermore, TIMP-1 weakly inhibited proliferation of VEGF-stimulated endothelial cells. In conclusion, our results provide evidence that TIMP-1 increases the production of sVEGFR-1 in endothelial cells and thus may reduce VEGF bioavailability, leading to reduced blood vessel growth in the ovary.