Genetic Signatures From RNA Sequencing of Pediatric Localized Scleroderma Skin

Abstract

The purpose of this study was to explore the skin transcriptional profile in pediatric localized scleroderma (LS) to provide a better understanding of the altered immune and fibrotic pathways promoting disease. LS is a progressive disease of the skin and underlying tissue that causes significant functional disability and disfigurement, especially in developing children. RNA sequencing (RNAseq) technology allows for improved understanding of relevant cellular expression through transcriptome analysis of phases during LS disease progression (more active/inflammatory vs. inactive/fibrotic) and also permits the use of RNA extracted from existing paraffin-embedded skin tissue, which is important in pediatrics. A strong correlation was observed between the comparison of genes expressed between fresh (RNAlater) and paraffinized skin in healthy and LS subjects, supporting the use of paraffinized tissue. LS gene signatures compared to healthy controls showed a distinct expression of an inflammatory response gene signature (IRGS) composed of IFNγ-, IFNα-, and TNFα-associated genes. GSEA© enrichment analysis showed that the IRGS, including interferon-inducible chemokines such as CXCL9, CXCL10, CXCL11, and IFNγ itself, was more highly expressed in LS patients with more inflammatory lesions. The use of paraffinized skin for sequencing was proven to be an effective substitute for fresh skin by comparing gene expression profiles. The prevalence of the IFNγ signature in the lesion biopsies of active LS patients indicates that these genes reflect clinical activity parameters and may be the promoters of early, inflammatory disease.

Morphea after initiation of dupilumab in two pediatric atopic dermatitis patients

“…In support of this hypothesis, flow cytometry studies show a Th1 inflammatory signature in localized scleroderma peripheral blood mononuclear cells 13 . Studies of transcripts of transcriptional profiles and cytokine levels suggest that levels of CXCL9/10/11 and IFN‐γ, which play a role in differentiation of Th1 cells, are higher in localized scleroderma patients with more inflammatory disease 14–17 . Increased macrophage infiltration, CXCL9, and IFN‐γ expression were seen in localized scleroderma tissue compared to healthy tissue and showed staining in close approximation with CXCR3 + T cells 15,17 .…”

“…13 Studies of transcripts of transcriptional profiles and cytokine levels suggest that levels of CXCL9/10/11 and IFN-γ, which play a role in differentiation of Th1 cells, are higher in localized scleroderma patients with more inflammatory disease. [14][15][16][17] Increased macrophage infiltration, CXCL9, and IFN-γ expression were seen in localized scleroderma tissue compared to healthy tissue and showed staining in close approximation with CXCR3 + T cells. 15,17 These studies may suggest that the imbalance in IFN-γ, CXCL9, and CXCL10 secreted by F I G U R E 1 Patients on dupilumab for atopic dermatitis.…”

Morphea: The 2023 update

“…These cytokines probably determine the direction of the immune response and control the disease severity. Less data is available on cytokine profiles in skin lesions, but recently published juvenile morphea gene signatures compared to healthy controls showed an inflammatory response gene signature composed of IFN-γ-, IFN-α-, and tumor necrosis factor-α-associated genes like chemokine (C-X-C motif) ligand (CXCL)-9, CXCL-10, CXCL-11 and IFN-γ itself in correlation with the clinical disease activity ( 45 , 46 ).…”

Modern approaches to understanding immunopathogenesis of scleroderma (review)

“…У детей, страдающих очаговой склеродермией либо ювенильной системной склеродермией, выявляется более высокое содержание CD4+ клеток-хелперов периферической крови. Повышение содержания CD4+ тесно связано с показателями активности очаговой склеродермии [18].…”