Dermatology Commons^™

Reduced Spag17 Expression In Systemic Sclerosis Triggers Myofibroblast Transition And Drives Fibrosis, Paulene Sapao, Elisha D O Roberson, Bo Shi, Shervin Assassi, Brian Skaug, Fred Lee, Alexandra Naba, Bethany E Perez White, Carlos Córdova-Fletes, Pei-Suen Tsou, Amr H Sawalha, Johann E Gudjonsson, Feiyang Ma, Priyanka Verma, Dibyendu Bhattacharyya, Mary Carns, Jerome F Strauss, Delphine Sicard, Daniel J Tschumperlin, Melissa I Champer, Paul J Campagnola, Maria E Teves, John Varga

Journal Articles

Systemic sclerosis (SSc) is a clinically heterogeneous fibrotic disease with no effective treatment. Myofibroblasts are responsible for unresolving synchronous skin and internal organ fibrosis in SSc, but the drivers of sustained myofibroblast activation remain poorly understood. Using unbiased transcriptome analysis of skin biopsies, we identified the downregulation of SPAG17 in multiple independent cohorts of patients with SSc, and by orthogonal approaches, we observed a significant negative correlation between SPAG17 and fibrotic gene expression. Fibroblasts and endothelial cells explanted from SSc skin biopsies showed reduced chromatin accessibility at the SPAG17 locus. Remarkably, mice lacking Spag17 showed spontaneous skin fibrosis with increased …

Aptamer Proteomics Of Serum Exosomes From Patients With Primary Raynaud's And Patients With Raynaud's At Risk Of Evolving Into Systemic Sclerosis, Sonsoles Piera-Velazquez, Simon T. Dillon, Xuesong Gu, Towia A. Libermann, Sergio A. Jimenez

Department of Dermatology and Cutaneous Biology Faculty Papers

BACKGROUND: A major unmet need for Systemic Sclerosis (SSc) clinical management is the lack of biomarkers for the early diagnosis of patients with Raynaud's Phenomenon at high risk of evolving into SSc.

OBJECTIVE: To identify proteins contained within serum exosomes employing an aptamer proteomic analysis that may serve to reveal patients with Raynaud's Phenomenon at risk of developing SSc.

METHODS: Exosomes were isolated from serum samples from patients with Primary Raynaud's Phenomenon and from patients with Raynaud's Phenomenon harbouring serum antinuclear antibodies (ANA) who may be at high risk of evolving into SSc. The expression of 1,305 proteins was quantified …

Effect Of Oxidative Stress On Protein Tyrosine Phosphatase 1b In Scleroderma Dermal Fibroblasts., Pei-Suen Tsou, Nadine N. Talia, Adam J. Pinney, Ann Kendzicky, Sonsoles Piera-Velazquez, Sergio A. Jimenez, James R. Seibold, Kristine Phillips, Alisa E Koch

Department of Dermatology and Cutaneous Biology Faculty Papers

OBJECTIVE: Platelet-derived growth factor (PDGF) and its receptor, PDGFR, promote fibrosis in systemic sclerosis (SSc; scleroderma) dermal fibroblasts, and such cells in scleroderma skin lesions produce excessive reactive oxygen species (ROS). PDGFR is phosphorylated upon PDGF stimulation, and is dephosphorylated by protein tyrosine phosphatases (PTPs), including PTP1B. This study was undertaken to determine whether the thiol-sensitive PTP1B is affected by ROS in SSc dermal fibroblasts, thereby enhancing the phosphorylation of PDGFR and synthesis of type I collagen. This study also sought to investigate the effect of a thiol antioxidant, N-acetylcysteine (NAC), in SSc.

METHODS: Fibroblasts were isolated from the skin …

Biomarkers In Systemic Sclerosis., Susan V. Castro, Sergio A. Jimenez

Scleroderma Center Faculty Papers

Systemic sclerosis is an autoimmune inflammatory disorder of unknown etiologycharacterized b y pronounced fibroproliferative alterations in the microvasculature, and frequent cellular and humoral immunity abnormalities, culminating in a severe and often progressive fibrotic process. Numerous biomarkers reflecting the three main pathogenetic mechanisms in systemic sclerosis have been described; however, aside from several disease-specific autoantibodies, other biomarkers have not been thoroughly validated and require further study. Thus, there is an unmet need for validated biomarkers for diagnosis, disease classification, and evaluation of organ involvement and therapeutic response in systemic sclerosis.

Elevated Expression Of Type Vii Collagen In The Skin Of Patients With Systemic Sclerosis. Regulation By Transforming Growth Factor-Beta., Lidia Rudnicka, John Varga, Angela M. Christiano, Renato V. Iozzo, Sergio A. Jimenez, Jouni Uitto

Department of Dermatology and Cutaneous Biology Faculty Papers

A hallmark of systemic sclerosis (SSc) is the development of tissue fibrosis. Excessive production of several connective tissue components normally present in the dermis, including type I, III, V, and VI collagens as well as fibronectin and proteoglycans, is a consistent finding in the skin of SSc patients. Type VII collagen is a major constituent of anchoring fibrils, present in the skin at the dermal-epidermal basement membrane zone. TGF-beta has been shown to upregulate the expression of the type VII collagen gene. In this study, we assessed the expression of type VII collagen and TGF-beta in the skin of patients …