In two phase 3 trials of identical design involving patients with atopic dermatitis, dupilumab improved the signs and symptoms of atopic dermatitis, including pruritus, symptoms of anxiety and depression, and quality of life, as compared with placebo. Trials of longer duration are needed to assess the long-term effectiveness and safety of dupilumab. (Funded by Sanofi and Regeneron Pharmaceuticals; SOLO 1 ClinicalTrials.gov number, NCT02277743 ; SOLO 2 ClinicalTrials.gov number, NCT02277769 .).

Patients treated with dupilumab had marked and rapid improvement in all the evaluated measures of atopic dermatitis disease activity. Side-effect profiles were not dose-limiting. (Funded by Regeneron Pharmaceuticals and Sanofi; ClinicalTrials.gov numbers, NCT01259323, NCT01385657, NCT01639040, and NCT01548404.).

Summary Background Psoriasis vulgaris is an inflammatory skin disease mediated by Th1 and Th17 cytokines, yet the relative contribution of interferon (IFN)-γ, interleukin (IL)-17 and IL-22 on disease pathogenesis is still unknown. Objectives In this study, we sought to identify the cytokines produced by skin-resident T cells in normal skin, localize the receptors for these cytokines, and examine how these cytokines alter gene expression profiles of the cells bearing cognate receptors. Methods We used intracellular cytokine staining and flow cytometry to evaluate T cell cytokine production, and immunohistochemistry and double-label immunofluorescence to localize cytokine receptors in skin. Gene array analysis of cytokine-treated keratinocytes was performed using moderated paired t-test controlling for false discovery rate using the Benjamini–Hochberg procedure. Results We demonstrate that T-helper cells producing IL-17, IL-22 and/or IFN-γ, as well as the cells bearing cognate cytokine receptors, are present in normal human skin. Keratinocytes stimulated with IL-17 expressed chemokines that were different from those induced by IFN-γ, probably contributing to the influx of neutrophils, dendritic cells and memory T cells into the psoriatic lesion. In contrast, IL-22 downregulated genes associated with keratinocyte differentiation and caused epidermal alterations in an organotypic skin model. Conclusions Our results suggest that the Th17 cytokines IL-17 and IL-22 mediate distinct downstream pathways that contribute to the psoriatic phenotype: IL-17 is more proinflammatory, while IL-22 retards keratinocyte differentiation.

Background Atopic dermatitis (AD) is a common disease, with an increasing prevalence. The primary pathogenesis of the disease is still elusive, resulting in the lack of specific treatments. AD is currently considered a biphasic disease, with Th2 predominating acute disease, and a switch to Th1 characterizing chronic disease. Elucidation of the molecular factors that participate in the onset of new lesions and maintenance of chronic disease is critical for the development of targeted therapeutics. Objectives We sought to characterize the mechanisms underlying onset and maintenance of AD. Methods We investigated intrapersonal sets of transcriptomes from non-lesional, acute and chronic lesions of ten AD patients through genomic, molecular and cellular profiling. Results Our study associated the onset of acute lesions with a striking increase in a subset of terminal differentiation proteins, specifically the cytokine-modulated S100A7, S100A8, and S100A9. Acute disease was also associated with significant increases in gene expression levels of major Th22- and Th2- cytokines, and smaller increases in IL-17. A lesser induction of Th1-associated genes was detected in acute disease, although some were significantly up-regulated in chronic disease. Further significant intensification of major Th22 and Th2 cytokines was observed between acute and chronic lesions. Conclusions Our data identified increased S100A7, S100A8 and S100A9 gene expression with AD initiation, and concomitant activation of Th2 and Th22 cytokines. Our findings support a model of progressive activation of Th2 and Th22 immune axes from acute to chronic phases, expanding the prevailing view of pathogenesis, with important therapeutic implications.

Dupilumab-mediated inhibition of IL-4/IL-13 signaling through IL-4 receptor α blockade significantly and progressively improved disease activity, suppressed cellular/molecular cutaneous markers of inflammation and systemic measures of type 2 inflammation, and reversed AD-associated epidermal abnormalities.

Psoriasis is a complex inflammatory disease mediated by tumor necrosis factor (TNF)-α and cytokines secreted by specialized T-cell populations, e.g., IL-17, IL-22, and IFN-γ. The mechanisms by which innate and adaptive immune cytokines regulate inflammation in psoriasis are not completely understood. We sought to investigate the effects of TNF-α and IL-17 on keratinocyte (KC) gene profile, to identify genes that might be coregulated by these cytokines and determine how synergistically activated genes relate to the psoriasis transcriptome. Primary KCs were stimulated with IL-17 or TNF-α alone, or in combination. KC responses were assessed by gene array analysis, followed by reverse transcriptase-PCR confirmation for significant genes. We identified 160 genes that were synergistically upregulated by IL-17 and TNF-α, and 196 genes in which the two cytokines had at least an additive effect. Synergistically upregulated genes included some of the highest expressed genes in psoriatic skin with an impressive correlation between IL-17/TNF-α-induced genes and the psoriasis gene signature. KCs may be key drivers of pathogenic inflammation in psoriasis through integrating responses to TNF-α and IL-17. Our data predict that psoriasis therapy with either TNF or IL-17 antagonists will produce greater modulation of the synergistic/additive gene set, which consists of the most highly expressed genes in psoriasis skin lesions.

Background-Psoriasis and atopic dermatitis (AD) are common inflammatory skin diseases. Upregulated Th17/IL-23 pathway was demonstrated in psoriasis. Although potential involvement of Th17 T-cells in AD was suggested during acute disease, the role of these cells in chronic AD remains unclear.

Atopic dermatitis (AD) is a complex skin disease frequently associated with other diseases of the atopic diathesis. Recent evidence supports the concept that AD can also recognize other comorbidities, such as chronic inflammatory bowel or cardiovascular diseases. These comorbidities might result from chronic cutaneous inflammation or from a common, yet-to-be-defined immunologic background leading to immune deviations. The activation of immune cells and their migration to the skin play an essential role in the pathogenesis of AD. In patients with AD, an underlying immune deviation might result in higher susceptibility of the skin to environmental factors. There is a high unmet medical need to define immunologic endotypes of AD because it has significant implications on upcoming stratification of the phenotype of AD and the resulting targeted therapies in the development of precision medicine. This review article emphasizes studies on environmental factors affecting AD development and novel biological agents used in the treatment of AD. Best evidence of the clinical efficacy of novel immunologic approaches using biological agents in patients with AD is available for the anti-IL-4 receptor α-chain antibody dupilumab, but a number of studies are currently ongoing with other specific antagonists to immune system players. These targeted molecules can be expressed on or drive the cellular players infiltrating the skin (eg, T lymphocytes, dendritic cells, or eosinophils). Such approaches can have immunomodulatory and thereby beneficial clinical effects on the overall skin condition, as well as on the underlying immune deviation that might play a role in comorbidities. An effect of these immunologic treatments on pruritus and the disturbed microbiome in patients with AD has other potential consequences for treatment.