Dysfunctional epidermis increases dermis inflammation in systemic sclerosis: results from a novel epidermal equivalent engineered from SSc keratinocytes.
Ontology highlight
ABSTRACT: In systemic sclerosis (SSc) evidence suggests abnormal keratinocyte-fibroblast interactions. We investigated the potential epidermal dysfunction in SSc and its effects on dermis homeostasis. Epidermal equivalents (EE) were generated from six healthy donor (HD) and four SSc keratinocytes. Skin and EE expression of proliferation, differentiation, and activation markers was evaluated by immunohistochemistry. The transcriptomic profile of SSc-EE and HD-EE was identified by RNAseq analysis. EE conditioned medium (CM) was used to stimulate fibroblasts, and their production of interleukin (IL)-6, IL-8, matrix metalloproteinase (MMP)-1, type-I collagen (col-I), and fibronectin was assessed by ELISA. Compared to HD, SSc-EE exhibited aberrant differentiation, enhanced expression of activation markers, and lower mitotic rate of basal keratinocytes, reproducing most of the abnormalities observed in SSc epidermis. RNAseq analysis revealed that, compared to HD-EE, SSc-EE were characterized by the downregulation of HOX gene family members and by the upregulation of metabolic and oxidative stress molecular pathways. EE-CM enhanced the fibroblast production of IL-6, IL-8, MMP-1, Col-I, and fibronectin (p<0.05). Except for Col-I and fibronectin, this effect was 2-fold higher in the presence of CM generated form SSc-EE. IL-1 was, at least in part, responsible for keratinocyte-dependent fibroblast activation. SSc-EE recapitulate the in vivo characteristic of SSc epidermis demonstrating that SSc keratinocytes have an intrinsically altered differentiation program possibly due to the downregulation of genes from the HOX family. The increased metabolic and oxidative stress associated with SSc epidermis may participate to dermis chronic inflammation and fibrosis
ORGANISM(S): Homo sapiens
PROVIDER: GSE156173 | GEO | 2021/08/13
REPOSITORIES: GEO
ACCESS DATA