Persistence of Inflammatory Phenotype in Residual Psoriatic Plaques in Patients on Effective Biologic Therapy

Many psoriasis patients treated with biologics do not achieve total skin clearance. These patients possess residual plaques despite ongoing biologic treatment. To elucidate mechanisms of plaque persistence despite overall good drug response, we studied 50 subjects: psoriasis patients with residual plaques treated with one of three different biologics, untreated patients, and healthy controls. Skin biopsies from all subjects were characterized using three methods: mRNA expression, histology, and FACS of hematopoietic skin cells. Although all three methods provided evidence of drug effect, gene expression analysis revealed the persistence of key psoriasis pathways in treated plaques, including granulocyte adhesion and diapedesis, T helper type17 activation pathway, and interferon signaling with no novel pathways emerging. Focal decreases in parakeratosis and keratinocyte proliferation and differential reduction in IL-17 producing CD103- T cells, but no change in CD103+ tissue-resident memory T cells were observed. Of note, antitumor necrosis factor increased the interferon signaling pathway already present. Interestingly mast cells were the dominant source of IL-22 in all psoriasis subjects. These data suggest that while subtle differences can be observed in drug-treated plaques, underlying biologic mechanisms are similar to those present in untreated psoriatic lesions.

The Safety and Efficacy of Roflumilast Cream 0.15% and 0.05% in Patients With Atopic Dermatitis: Randomized, Double-Blind, Phase 2 Proof of Concept Study

BACKGROUND

Patients with atopic dermatitis (AD) need safe and effective topical treatments.

OBJECTIVE

To assess safety and efficacy of roflumilast cream in patients with mild to moderate AD.

METHODS

In this phase 2, proof of concept trial, patients (N=136) aged ≥12 years with AD were randomized to once-daily roflumilast cream 0.15%, roflumilast cream 0.05%, or vehicle cream for 4 weeks. Absolute change from baseline in Eczema Area and Severity Index (EASI) score at week 4 (primary endpoint), percentage change and responder rates, Validated Investigator Global Assessment-AD (vIGA-AD), and safety were assessed.

RESULTS

At week 4, mean absolute changes in EASI were −6.4 (P=0.097 vs vehicle), −6.0 (P=0.356), and −4.8 with roflumilast 0.15%, roflumilast 0.05%, and vehicle, respectively. Significant improvements were observed for percentage change from baseline in EASI, patients reaching 75% improvement in EASI, and patients achieving vIGA-AD score of “clear” or “almost clear.” Treatment-related adverse events (AEs) occurred in 2 (2.2%) patients receiving roflumilast (mild rash and moderate application site pain). Only 1 (1.1%) patient receiving roflumilast discontinued study/drug due to an AE.

LIMITATIONS

Small number of patients.

CONCLUSIONS

Results support additional larger clinical trials of roflumilast cream to assess its potential as a once-daily, nonsteroidal topical AD treatment.

CLINICALTRIALS

gov identifier NCT03916081 J Drugs Dermatol. 2023;22(2):139-147. doi:10.36849/JDD.7295.

Intrapatient comparison of atopic dermatitis skin transcriptome shows differences between tape-strips and biopsies

BACKGROUND

Our knowledge of etiopathogenesis of atopic dermatitis (AD) is largely derived from skin biopsies, which are associated with pain, scarring and infection. In contrast, tape-stripping is a minimally invasive, nonscarring technique to collect skin samples.

METHODS

To construct a global AD skin transcriptomic profile comparing tape-strips to whole-skin biopsies, we performed RNA-seq on tape-strips and biopsies taken from the lesional skin of 20 moderate-to-severe AD patients and the skin of 20 controls. Differentially expressed genes (DEGs) were defined by fold-change (FCH) ≥2.0 and false discovery rate <0.05.

RESULTS

We detected 4104 (2513 Up; 1591 Down) and 1273 (546 Up; 727 Down) DEGs in AD versus controls, in tape-strips and biopsies, respectively. Although both techniques captured dysregulation of key immune genes, tape-strips showed higher FCHs for innate immunity (IL-1B, IL-8), dendritic cell (ITGAX/CD11C, FCER1A), Th2 (IL-13, CCL17, TNFRSF4/OX40), and Th17 (CCL20, CXCL1) products, while biopsies showed higher upregulation of Th22 associated genes (IL-22, S100As) and dermal cytokines (IFN-γ, CCL26). Itch-related genes (IL-31, TRPV3) were preferentially captured by tape-strips. Epidermal barrier abnormalities were detected in both techniques, with terminal differentiation defects (FLG2, PSORS1C2) better represented by tape-strips and epidermal hyperplasia changes (KRT16, MKI67) better detected by biopsies.

CONCLUSIONS

Tape-strips and biopsies capture overlapping but distinct features of the AD molecular signature, suggesting their respective utility for monitoring specific AD-related immune, itch, and barrier abnormalities in clinical trials and longitudinal studies.

Establishment of a comprehensive reference transcriptome for vertebral bone tissue to study the impacts of nutritional phosphorus deficiency in rainbow trout (Oncorhynchus mykiss, Walbaum)

Reducing dietary phosphorus (P) is a common approach to reduce effluent P outputs. The potential resulting P-deficiency is known to negatively impact fish bone condition and might result in vertebral deformities. To date, no large-scale study involving deep sequencing of the bone transcriptome has been conducted in salmonids and vertebral molecular changes remain poorly described. This study aims to provide the first comprehensive vertebral transcriptome for rainbow trout (Oncorhynchus mykiss) to allow functional and quantitative expression studies. Fish weighing 60.8±1.6g, were fed for 27weeks using two practical diets having 0.29% (deficient) and 0.45% (sufficient) available phosphorus (P), respectively. Deep sequencing was conducted using HiSeq2000 Illumina 100 paired-end technology from pooled P-deficient and P-sufficient fish and individuals displaying vertebral deformities. Over 140 million trimmed paired-end reads were assembled de novo with Trinity and resulted in 679,869 transcripts with a mean length of 542.5bp. From these sequences, 340,747 matched with referenced ESTs from rainbow trout. Furthermore, 141,909 and 117,564 sequences were functionally annotated against Nr and Uniprot databases, respectively. Interestingly, we observed putative homologue sequences for most of the key components involved in bone formation and turnover in mammals.

A novel nonsense mutation in exon 9 in the extracellular matrix protein 1 gene associated with lipoid proteinosis: A case report

Lipoid proteinosis is a rare autosomal recessive genodermatosis that is caused by loss-of-function mutations in the extracellular matrix protein 1 gene. This study identifies a novel nonsense mutation in exon 9 of the extracellular matrix protein 1 gene associated with lipoid proteinosis, contributing to recent advances in our understanding of the molecular genetics underlying this disease. It is important to identify the mutations in the extracellular matrix protein 1 gene that are associated with lipoid proteinosis and how these affect protein function. Understanding the molecular basis for such genetic disorders may lead to novel therapeutic approaches for treating hereditary genodermatoses.

Ethnicity, Race and Skin Color: Challenges and Opportunities for Atopic Dermatitis Clinical Trials

The number of clinical trials conducted in patients with atopic dermatitis is increasing steadily. These trials are conducted in several countries across all continents and include patients of different ethnicity, race and skin color. This diversity is desired, but it also brings challenges, including the diagnosis and evaluation of disease severity in patients with different skin colors; the influence of ethnicity on the perception of quality of life and patient reported outcomes; the inclusion of ethnicities that are only present in one country or that live far from clinical research sites; and the reporting of drug safety information. There is a need to better train physicians on the evaluation of atopic dermatitis in patients with different skin colors and a need to improve the systematic reporting of ethnicity, race and skin color in clinical trial publications.