Possible role of BMP-4 in the hyper-pigmentation of psoriatic plaques after anti-TNF-α treatment

Clinical, dermoscopic, and ultrasonic monitoring of the response to biologic treatment in patients with moderate-to-severe plaque psoriasis

Background

Assessment of therapeutic response of psoriasis has relied traditionally on clinical observation, and effective non-invasive tools are desirable.

Objectives

To investigate the value of dermoscopy and high-frequency ultrasound (HFUS) in the monitoring of psoriatic lesions treated with biologics.

Methods

Patients with moderate-to-severe plaque psoriasis treated with biologics were evaluated by clinical, dermoscopic, and ultrasonic scores at weeks 0, 4, 8, and 12. Clinical scores, including Psoriasis Area Severity Index (PASI) and target lesion score (TLS), were evaluated at representative lesions. Dermoscopy was performed to assess the red background, vessels, and scales on a 4-point scale as well as the presence of hyperpigmentation, hemorrhagic spots, and linear vessels. HFUS was performed to measure the thicknesses of the superficial hyperechoic band and subepidermal hypoechoic band (SLEB). The correlation between clinical, dermoscopic, and ultrasonic evaluation was also analyzed.

Results

In total, 24 patients were analyzed and achieved 85.3 and 87.5% reduction of PASI and TLS, respectively, after 12 weeks of treatment. The red background, vessels, and scales scores under dermoscopy were reduced by 78.5, 84.1, and 86.5%, respectively. Some patients developed hyperpigmentation and linear vessels after treatment. Hemorrhagic dots slowly subside over the therapeutic course. Ultrasonic scores were significantly improved with an average reduction of 53.9% in superficial hyperechoic band thickness and 89.9% in SLEB thickness. TLS in the clinical variables, scales in dermoscopic variables, and SLEB in ultrasonic variables decreased the most significantly in the early stage of treatment (week 4) with 55.4, 57.7, and 59.1% (P > 0.05), respectively. Most of the variables, including the red background, vessels, scales, and SLEB thickness, were strongly correlated with TLS. High correlations were also found between the SLEB thickness and the red background or vessels scores, and between the superficial hyperechoic band thickness and the scales scores.

Conclusion

Both dermoscopy and HFUS were useful in the therapeutic monitoring of moderate-to-severe plaque psoriasis.

DNA Methylation Patterns in CD8+ T Cells Discern Psoriasis From Psoriatic Arthritis and Correlate With Cutaneous Disease Activity

Background: Psoriasis is a T cell-mediated chronic autoimmune/inflammatory disease. While some patients experience disease limited to the skin (skin psoriasis), others develop joint involvement (psoriatic arthritis; PsA). In the absence of disease- and/or outcome-specific biomarkers, and as arthritis can precede skin manifestations, diagnostic and therapeutic delays are common and contribute to disease burden and damage accrual.

Objective: Altered epigenetic marks, including DNA methylation, contribute to effector T cell phenotypes and altered cytokine expression in autoimmune/inflammatory diseases. This project aimed at the identification of disease-/outcome-specific DNA methylation signatures in CD8⁺ T cells from patients with psoriasis and PsA as compared to healthy controls.

Method: Peripheral blood CD8⁺ T cells from nine healthy controls, 10 psoriasis, and seven PsA patients were collected to analyze DNA methylation marks using Illumina Human Methylation EPIC BeadChips (>850,000 CpGs per sample). Bioinformatic analysis was performed using R (minfi, limma, ChAMP, and DMRcate packages).

Results: DNA methylation profiles in CD8⁺ T cells differentiate healthy controls from psoriasis patients [397 Differentially Methylated Positions (DMPs); 9 Differentially Methylated Regions (DMRs) when ≥CpGs per DMR were considered; 2 DMRs for ≥10 CpGs]. Furthermore, patients with skin psoriasis can be discriminated from PsA patients [1,861 DMPs, 20 DMRs (≥5 CpGs per region), 4 DMRs (≥10 CpGs per region)]. Gene ontology (GO) analyses considering genes with ≥1 DMP in their promoter delivered methylation defects in skin psoriasis and PsA primarily affecting the BMP signaling pathway and endopeptidase regulator activity, respectively. GO analysis of genes associated with DMRs between skin psoriasis and PsA demonstrated an enrichment of GABAergic neuron and cortex neuron development pathways. Treatment with cytokine blockers associated with DNA methylation changes [2,372 DMPs; 1,907 DMPs within promoters, 7 DMRs (≥5 CpG per regions)] affecting transforming growth factor beta receptor and transmembrane receptor protein serine/threonine kinase signaling pathways. Lastly, a methylation score including TNF and IL-17 pathway associated DMPs inverse correlates with skin disease activity scores (PASI).

Conclusion: Patients with skin psoriasis exhibit DNA methylation patterns in CD8⁺ T cells that allow differentiation from PsA patients and healthy individuals, and reflect clinical activity of skin disease. Thus, DNA methylation profiling promises potential as diagnostic and prognostic tool to be used for molecular patient stratification toward individualized treatment.