Jon M. Hanifin

Duration of antiviral immunity after smallpox vaccination

Although naturally occurring smallpox was eliminated through the efforts of the World Health Organization Global Eradication Program, it remains possible that smallpox could be intentionally released. Here we examine the magnitude and duration of antiviral immunity induced by one or more smallpox vaccinations. We found that more than 90% of volunteers vaccinated 25–75 years ago still maintain substantial humoral or cellular immunity (or both) against vaccinia, the virus used to vaccinate against smallpox. Antiviral antibody responses remained stable between 1–75 years after vaccination, whereas antiviral T-cell responses declined slowly, with a half-life of 8–15 years. If these levels of immunity are considered to be at least partially protective, then the morbidity and mortality associated with an intentional smallpox outbreak would be substantially reduced because of pre-existing immunity in a large number of previously vaccinated individuals.

THE ECZEMA AREA AND SEVERITY INDEX (EASI): ASSESSMENT OF RELIABILITY IN ATOPIC DERMATITIS

Abstract: Objective– To test the reliability of the eczema area and severity index (EASI) scoring system by assessing inter‐ and intra‐observer consistency. Design: Training of evaluators, application, and assessment over 2 consecutive days. Setting– An academic center. Patients– Twenty adults and children with atopic dermatitis (AD); cohort 1 (10 patients ≥8 years) and cohort 2 (10 patients <8 years). Interventions– None. Main outcome measure– The EASI was used by 15 dermatologist evaluators to assess atopic dermatitis in cohort 1 and cohort 2 on 2 consecutive days. Inter‐ and intraobserver reliability were analyzed. Results– Overall intra‐evaluator reliability of the EASI was in the fair‐to‐good range. Inter‐evaluator reliability analyses indicated that the evaluators assessed the patients consistently across both study days. Conclusions– This study demonstrated that the EASI can be learned quickly and utilized reliably in the assessment of severity and extent of AD. There was consistency among the evaluators between consecutive days of evaluation. These results support the use of the EASI in clinical trials of therapeutic agents for AD.

Presence of IgE antibodies to staphylococcal exotoxins on the skin of patients with atopic dermatitis. Evidence for a new group of allergens.

In the current study, we investigated whether Staphylococcus aureus grown from affected skin of atopic dermatitis (AD) patients secreted identifiable toxins that could act as allergens to induce IgE-mediated basophil histamine release. The secreted toxins of S. aureus grown from AD patients were identified by ELISA using antibodies specific for staphylococcal enterotoxin (SE) exfoliative toxin (ET), or toxic shock syndrome toxin (TSST-1). S. aureus isolates from 24 of 42 AD patients secreted identifiable toxins with SEA, SEB, and TSST accounting for 92% of the isolates. 32 of 56 AD sera (57%) tested contained significant levels of IgE primarily to SEA, SEB, and/or TSST. In contrast, although SEA, SEB, or TSST secreting S. aureus could be recovered from the skin of psoriasis patients, their sera did not contain IgE antitoxins. Freshly isolated basophils from 10 AD patients released 5-59% of total histamine in response to SEA, SEB, or TSST-1 but only with toxins to which patients had specific IgE. Basophils from eight other AD patients and six normal controls who had no IgE antitoxin failed to demonstrate toxin-induced basophil histamine release. Stripped basophils sensitized with three AD sera containing IgE to toxin released 15-41% of total basophil histamine only when exposed to the relevant toxin, but not to other toxins. Sensitization of basophils with AD sera lacking IgE antitoxin did not result in release of histamine to any of the toxins tested. These data indicate that a subset of patients with AD mount an IgE response to SEs that can be grown from their skin. These toxins may exacerbate AD by activating mast cells, basophils, and/or other Fc epsilon-receptor bearing cells armed with the relevant IgE antitoxin.

Tight junction defects in patients with atopic dermatitis.

BACKGROUND Atopic dermatitis (AD) is characterized by dry skin and a hyperactive immune response to allergens, 2 cardinal features that are caused in part by epidermal barrier defects. Tight junctions (TJs) reside immediately below the stratum corneum and regulate the selective permeability of the paracellular pathway. OBJECTIVE We evaluated the expression/function of the TJ protein claudin-1 in epithelium from AD and nonatopic subjects and screened 2 American populations for single nucleotide polymorphisms in the claudin-1 gene (CLDN1). METHODS Expression profiles of nonlesional epithelium from patients with extrinsic AD, nonatopic subjects, and patients with psoriasis were generated using Illuminas BeadChips. Dysregulated intercellular proteins were validated by means of tissue staining and quantitative PCR. Bioelectric properties of epithelium were measured in Ussing chambers. Functional relevance of claudin-1 was assessed by using a knockdown approach in primary human keratinocytes. Twenty-seven haplotype-tagging SNPs in CLDN1 were screened in 2 independent populations with AD. RESULTS We observed strikingly reduced expression of the TJ proteins claudin-1 and claudin-23 only in patients with AD, which were validated at the mRNA and protein levels. Claudin-1 expression inversely correlated with T(H)2 biomarkers. We observed a remarkable impairment of the bioelectric barrier function in AD epidermis. In vitro we confirmed that silencing claudin-1 expression in human keratinocytes diminishes TJ function while enhancing keratinocyte proliferation. Finally, CLDN1 haplotype-tagging SNPs revealed associations with AD in 2 North American populations. CONCLUSION Collectively, these data suggest that an impairment in tight junctions contributes to the barrier dysfunction and immune dysregulation observed in AD subjects and that this may be mediated in part by reductions in claudin-1.

EPIDEMIOLOGY OF ATOPIC DERMATITIS

This article outlines the progress in the understanding of the epidemiology of atopic dermatitis (AD) during the last decade. Epidemiology concerns the occurrence of risk factors of the disease. In previous publications, criteria for defining AD have been developed to be used in clinical investigations and populationbased studies.

A randomized, vehicle-controlled trial of tacrolimus ointment for treatment of atopic dermatitis in children

BACKGROUND A topical formulation of tacrolimus, an immunosuppressant currently marketed for the prevention of rejection after solid organ transplant, is a potential therapeutic agent for atopic dermatitis. OBJECTIVE We sought to determine the safety and efficacy of tacrolimus ointment in pediatric patients with moderate-to-severe atopic dermatitis. METHODS In this double-blind, vehicle-controlled multicenter trial, children ages 7 to 16 years were treated with twice daily application of tacrolimus ointment at 1 of 3 concentrations (0.03% [n = 43], 0.1% [n = 49], or 0.3% [n = 44]) or vehicle (n = 44) for up to 22 days, with a 2-week follow-up period. RESULTS The Physicians Global Evaluation of clinical response showed that 69% (95% confidence interval: 53-82) of patients in the 0.03% tacrolimus ointment group, 67% (95% confidence interval: 52-81) in the 0.1% tacrolimus ointment group, and 70% (95% confidence interval: 54-83) in the 0.3% tacrolimus ointment group, compared with 38% (95% confidence interval: 24-54) in the vehicle group, had a marked to excellent (> or =75%) improvement or clearing of their atopic dermatitis (P =.005, .007, and .004, respectively for the 3 tacrolimus groups compared with the vehicle group). The mean percent improvement for a modified Eczema Area and Severity Index at end of treatment for each of the 3 tacrolimus groups (0.03%, 72%; 0.1%, 77%: and 0.3%, 81%) was significantly better than that of the vehicle group (26%; P <.001). The median percent reduction in pruritus was significantly greater for tacrolimus-treated patients (74% to 89%) than for vehicle-treated patients (51%, P = .027). No serious systemic adverse events were noted, and systemic absorption was minimal. CONCLUSION Tacrolimus ointment appears to be safe and effective in children with atopic dermatitis.

Guidelines of care for the management of atopic dermatitis: section 2. Management and treatment of atopic dermatitis with topical therapies.

Atopic dermatitis is a common and chronic, pruritic inflammatory skin condition that can affect all age groups. This evidence-based guideline addresses important clinical questions that arise in its management. In this second of 4 sections, treatment of atopic dermatitis with nonpharmacologic interventions and pharmacologic topical therapies are reviewed. Where possible, suggestions on dosing and monitoring are given based on available evidence.

Emollient enhancement of the skin barrier from birth offers effective atopic dermatitis prevention

Background Atopic dermatitis (atopic eczema) is a chronic inflammatory skin disease that has reached epidemic proportions in children worldwide and is increasing in prevalence. Because of the significant socioeconomic effect of atopic dermatitis and its effect on the quality of life of children and families, there have been decades of research focused on disease prevention, with limited success. Recent advances in cutaneous biology suggest skin barrier defects might be key initiators of atopic dermatitis and possibly allergic sensitization. Objective Our objective was to test whether skin barrier enhancement from birth represents a feasible strategy for reducing the incidence of atopic dermatitis in high-risk neonates. Methods We performed a randomized controlled trial in the United States and United Kingdom of 124 neonates at high risk for atopic dermatitis. Parents in the intervention arm were instructed to apply full-body emollient therapy at least once per day starting within 3 weeks of birth. Parents in the control arm were asked to use no emollients. The primary feasibility outcome was the percentage of families willing to be randomized. The primary clinical outcome was the cumulative incidence of atopic dermatitis at 6 months, as assessed by a trained investigator. Results Forty-two percent of eligible families agreed to be randomized into the trial. All participating families in the intervention arm found the intervention acceptable. A statistically significant protective effect was found with the use of daily emollient on the cumulative incidence of atopic dermatitis with a relative risk reduction of 50% (relative risk, 0.50; 95% CI, 0.28-0.9; P = .017). There were no emollient-related adverse events and no differences in adverse events between groups. Conclusion The results of this trial demonstrate that emollient therapy from birth represents a feasible, safe, and effective approach for atopic dermatitis prevention. If confirmed in larger trials, emollient therapy from birth would be a simple and low-cost intervention that could reduce the global burden of allergic diseases.

Guidelines of care for the management of atopic dermatitis: Section 3. Management and treatment with phototherapy and systemic agents

Atopic dermatitis is a chronic, pruritic inflammatory dermatosis that affects up to 25% of children and 2% to 3% of adults. This guideline addresses important clinical questions that arise in atopic dermatitis management and care, providing recommendations based on the available evidence. In this third of 4 sections, treatment of atopic dermatitis with phototherapy and systemic immunomodulators, antimicrobials, and antihistamines is reviewed, including indications for use and the risk-benefit profile of each treatment option.

Consensus conference on pediatric atopic dermatitis

C urrent information identifying risk factors for cutaneous diseases such as atopic dermatitis in childhood is limited. Cutaneous disease prevention programs and health promotion strategies in children and adolescents have not been addressed in a concerted way by government agencies or relevant medical societies. Disease-based interventions often emphasize adult disease, but many diseases may be prevented or minimized by intervention during childhood years. Research may be more effectively coordinated and carried out with the establishment of consensus on how best to diagnose and treat diseases such as atopic dermatitis (AD) in children and identify the most critical issues related to this condition. A consensus conference was convened by the American Academy of Dermatology on January 1921, 2001 to (1) define the core dermatologic issues related to AD in children and adolescents that can influence their dermatologic health over a lifetime and (2) prioritize future research efforts on epidemiology, pathogenesis, prevention, and management of AD. The following focus questions were addressed and responses/recommendations were developed: