Transcutaneous yellow fever vaccination of subjects with or without atopic dermatitis
Atopic dermatitis (AD) is a common inflammatory skin disease with a global prevalence ranging from 3% to 20%. Patients with AD have an increased risk for complications after viral infection (eg, herpes simplex virus), and vaccination of patients with AD with live vaccinia virus is contraindicated because of a heightened risk of eczema vaccinatum, a rare but potentially lethal complication associated with smallpox vaccination. We sought to develop a better understanding of immunity to cutaneous viral infection in patients with AD. In a double-blind randomized study we investigated the safety and immunogenicity of live attenuated yellow fever virus (YFV) vaccination of nonatopic subjects and patients with AD after standard subcutaneous inoculation or transcutaneous vaccination administered with a bifurcated needle. Viremia, neutralizing antibody, and antiviral T-cell responses were analyzed for up to 30 days after vaccination. YFV vaccination administered through either route was well tolerated. Subcutaneous vaccination resulted in higher seroconversion rates than transcutaneous vaccination but elicited similar antiviral antibody levels and T-cell responses in both the nonatopic and AD groups. After transcutaneous vaccination, both groups mounted similar neutralizing antibody responses, but patients with AD demonstrated lower antiviral T-cell responses by 30 days after vaccination. Among transcutaneously vaccinated subjects, a significant inverse correlation between baseline IgE levels and the magnitude of antiviral antibody and CD4(+) T-cell responses was observed. YFV vaccination of patients with AD through the transcutaneous route revealed that high baseline IgE levels provide a potential biomarker for predicting reduced virus-specific immune memory after transcutaneous infection with a live virus.
- [Show abstract] [Hide abstract] ABSTRACT: Atopic dermatitis (AD) is the most common inflammatory disease. The prevalence of allergic contact dermatitis to allergens (eg, fragrance) is higher in patients with AD, despite a trend toward weaker clinical allergic contact dermatitis reactions. The role of the AD skin phenotype in modulating allergic sensitization to common sensitizers has not been evaluated. We sought to investigate whether patients with AD have altered tissue immune responses on allergen challenge. Gene expression and immunohistochemistry studies were performed on biopsy specimens from 10 patients with AD and 14 patients without AD patch tested with common contact allergens (nickel, fragrance, and rubber). Although 1085 differentially expressed genes (DEGs) were commonly modulated in patch-tested skin from patients with AD and patients without AD versus control skin, 1185 DEGs were uniquely altered in skin from patients without AD, and only 246 DEGs were altered in skin from patients with AD. Although many inflammatory products (ie, matrix metalloproteinase 12/matrix metalloproteinase 1/S100A9) were upregulated in both groups, higher-magnitude changes and upregulation of interferon responses were evident only in the non-AD group. Stratification by allergen showed decreased expression of immune, TH1-subset, and TH2-subset genes in nickel-related AD responses, with increased TH17/IL-23 skewing. Rubber/fragrance showed similar trends of lesser magnitude. Negative regulators showed higher expression in patients with AD. Through contact sensitization, our study offers new insights into AD. Allergic immune reactions were globally attenuated and differentially polarized in patients with AD, with significant decreases in levels of TH1 products, some increases in levels of TH17 products, and inconsistent upregulation in levels of TH2 products. The overall hyporesponsiveness in skin from patients with background AD might be explained by baseline immune abnormalities, such as increased TH2, TH17, and negative regulator levels compared with those seen in non-AD skin. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.0Comments 4Citations
- [Show abstract] [Hide abstract] ABSTRACT: Eczema vaccinatum is a life-threatening complication of smallpox vaccination in patients with atopic dermatitis (AD) characterized by dissemination of vaccinia virus (VV) in the skin and internal organs. Mutations in the filaggrin (FLG) gene, the most common genetic risk factor for AD, confer a greater risk for eczema herpeticum in patients with AD, suggesting that it impairs the response to cutaneous viral infections. We sought to determine the effects of FLG deficiency on the response of mice to cutaneous VV inoculation. VV was inoculated by means of scarification of unsensitized skin or skin topically sensitized with ovalbumin in FLG-deficient flaky tail (ft/ft) mice or wild-type (WT) control mice. The sizes of primary and satellite skin lesions were measured, and hematoxylin and eosin staining was performed. VV genome copy numbers and cytokine mRNA levels were measured by using quantitative PCR. VV inoculation in unsensitized skin of ft/ft mice, independent of the matted hair mutation, resulted in larger primary lesions, more abundant satellite lesions, heavier viral loads in internal organs, greater epidermal thickness, dermal cellular infiltration, and higher local Il17a, Il4, Il13, and Ifng mRNA levels than in WT control mice. VV inoculation at sites of topical ovalbumin application amplified all of these features in ft/ft mice but had no detectable effect in WT control mice. The number of satellite lesions and the viral loads in internal organs after cutaneous VV inoculation were significantly reduced in both unsensitized and topically sensitized ft/ftxIl17a(-/-) mice. FLG deficiency predisposes to eczema vaccinatum. This is mediated primarily through production of IL-17A. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.0Comments 0Citations
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