Biofilm propensity of Staphylococcus aureus skin isolates is associated with increased atopic dermatitis severity and barrier dysfunction in the MPAACH pediatric cohort.

Background: Atopic dermatitis (AD) patients are often colonized with Staphylococcus aureus, and staphylococcal biofilms have been reported on adult AD skin lesions. The commensal S epidermidis can antagonize S aureus, although its role in AD is unclear. We sought to characterize S aureus and S epidermidis colonization and biofilm propensity and determine their associations with AD severity, barrier function, and epidermal gene expression in the first US early-life cohort of children with AD, the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children (MPAACH).

Events in Normal Skin Promote Early-Life Atopic Dermatitis-The MPAACH Cohort.

Background: Nonlesional skin in atopic dermatitis (AD) is abnormal, but the pathobiology of lesional and nonlesional skin and the definition of endotypes are poorly understood.

Objective: To define lesional and nonlesional endotypes of AD by building the first US-based early-life prospective cohort of children with AD, the Mechanisms of Progression from AD to Asthma in Children cohort.

Methods: We assessed lesional and nonlesional skin transepidermal water loss, filaggrin (FLG) and alarmin (S100A8, S100A9) expression, staphylococcal colonization, and patterns of aeroallergen and food sensitization to define nonlesional and lesional phenotypes and endotypes.

CD8+ and FoxP3+ T-cell infiltration in actinic cheilitis.

Background: Differences in immune profile between actinic cheilitis (AC), a precursor of lip squamous cell carcinoma, and normal lip vermillion (NL) have not been elucidated.

Objectives: To compare density, distribution, and ratios of CD8+ and FoxP3+ cells between AC and NL and assess their associations with clinicopathologic variables.

Methods: Samples of AC and NL obtained between 2001 and 2013 at the College of Dentistry of the University of Concepcion, Chile, were retrospectively analyzed for immunohistochemical detection of CD8+ and FoxP3+ cells.