The IgG response against Staphylococcus aureus is associated with severe atopic dermatitis in children

Abstract

Background

An altered immune response against Staphylococcus (S.) aureus might contribute to inflammation and barrier damage in atopic dermatitis (AD).

Objectives

We profiled IgG antibodies against 55 S. aureus antigens in sera of children with mild to severe AD using a Luminex assay. Additionally, we evaluated the association between IgG levels and disease severity.

Methods

In this cross-sectional study, we included children with AD of two interventional study cohorts, namely SMA (n= 131) and the older DAVOS cohort (n= 76). AD severity was assessed using the Self Administrated-Eczema Area and Severity Index (SA-EASI) and levels of thymus and activation-regulated chemokine (TARC) in serum. IgG antibody levels against 55 S. aureus antigens were quantified simultaneously using a Luminex assay. Pair-wise correlations were calculated between the 55 IgG levels using the Spearman rank correlation test. A linear regression analysis was performed to test for associations between 55 IgG levels and SA-EASI and TARC adjusting for age, sex and S. aureus colonisation.

Results

In the SMA cohort 16 antigens were associated with SA-EASI and 12 antigens were associated with TARC (10 overlapping antigens; P-values from 0.001 to 0.044). The associated IgG antibodies targeted mainly secreted proteins with immune-modulatory functions. In the DAVOS study, IgG levels against only four and one S. aureus antigen(s) were associated with SA-EASI and TARC, respectively (no overlap).

Conclusions

In young children, severity of AD is associated with an IgG response directed against S. aureus antigens with mainly immune-modulatory functions. These findings encourage further evaluation of the role of S. aureus in AD pathogenesis.

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