title: Transcriptional patterns in peritoneal tissue of encapsulating peritoneal sclerosis, a complication of chronic peritoneal dialysis.
abstract: Encapsulating peritoneal sclerosis (EPS) is a devastating complication of peritoneal dialysis (PD), characterized by marked inflammation and severe fibrosis of the peritoneum, and associated with high morbidity and mortality. EPS can occur years after termination of PD and, in severe cases, leads to intestinal obstruction and ileus requiring surgical intervention. Despite ongoing research, the pathogenesis of EPS remains unclear. We performed a global transcriptome analysis of peritoneal tissue specimens from EPS patients, PD patients without EPS, and uremic patients without history of PD or EPS (Uremic). Unsupervised and supervised bioinformatics analysis revealed distinct transcriptional patterns that discriminated these three clinical groups. The analysis identified a signature of 219 genes expressed differentially in EPS as compared to PD and Uremic groups. Canonical pathway analysis of differentially expressed genes showed enrichment in several pathways, including antigen presentation, dendritic cell maturation, B cell development, chemokine signaling and humoral and cellular immunity (P value<0.05). Further interactive network analysis depicted effects of EPS-associated genes on networks linked to inflammation, immunological response, and cell proliferation. Gene expression changes were confirmed by qRT-PCR for a subset of the differentially expressed genes. EPS patient tissues exhibited elevated expression of genes encoding sulfatase1, thrombospondin 1, fibronectin 1 and alpha smooth muscle actin, among many others, while in EPS and PD tissues mRNAs encoding leptin and retinol-binding protein 4 were markedly down-regulated, compared to Uremic group patients. Immunolocalization of Collagen 1 alpha 1 revealed that Col1a1 protein was predominantly expressed in the submesothelial compact zone of EPS patient peritoneal samples, whereas PD patient peritoneal samples exhibited homogenous Col1a1 staining throughout the tissue samples. The results are compatible with the hypothesis that encapsulating peritoneal sclerosis is a distinct pathological process from the simple peritoneal fibrosis that accompanies all PD treatment.
authors: Renal Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.
authors: Fabian R
authors: FR
authors: Reimold
authors: Niko
authors: N
authors: Braun
authors: Zsuzsanna K
authors: ZK
authors: Zsengellér
authors: Isaac E
authors: IE
authors: Stillman
authors: S Ananth
authors: SA
authors: Karumanchi
authors: Hakan R
authors: HR
authors: Toka
authors: Joerg
authors: J
authors: Latus
authors: Peter
authors: P
authors: Fritz
authors: Dagmar
authors: D
authors: Biegger
authors: Stephan
authors: S
authors: Segerer
authors: M Dominik
authors: MD
authors: Alscher
authors: Manoj K
authors: MK
authors: Bhasin
authors: Seth L
authors: SL
authors: Alper
mesh_terms: D000368:Aged; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D000090602:Collagen Type I, alpha 1 Chain; D005260:Female; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007674:Kidney Diseases / Q000628:therapy; D020738:Leptin / Q000235:genetics; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D010530:Peritoneal Dialysis / Q000009:adverse effects*; D056627:Peritoneal Fibrosis / Q000209:etiology / Q000235:genetics* / Q000378:metabolism; D010537:Peritoneum / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054839:Retinol-Binding Proteins, Plasma / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics
chemical_list: D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D020738:Leptin; C101326:RBP4 protein, human; D012333:RNA, Messenger; D054839:Retinol-Binding Proteins, Plasma