Human Adult Mesothelial Cells

Autophagy Promotes TGF-β1-Induced Epithelial-To-Mesenchymal Transition in Human Peritoneal Mesothelial Cells

Epithelial-to-mesenchymal transition (EMT) is one of the main causes of peritoneal fibrosis. However, the pathophysiological mechanisms of EMT, specifically its relationship with autophagy, are still unknown. This study aimed to evaluate the role of autophagy in transforming growth factor-beta 1 (TGF-β1)-induced EMT in human peritoneal mesothelial cells (HPMCs).

Primary cultured HPMCs were treated with TGF-β1 (2 and 5 ng/mL) and changes in autophagy markers and the relationship between autophagy and EMT were evaluated. TGF-β1 increased the generation of NADPH oxidase 4 (NOX4) and reactive oxygen species (ROS) in HPMCs, resulting in mitochondrial damage. Treatment with GKT137831 (20 μM), a NOX1/4 inhibitor, reduced ROS in the mitochondria of HPMC cells and reduced TGF-β1-induced mitochondrial damage. Additionally, the indirect inhibition of autophagy by GKT137831 (20 μM) downregulated TGF-β1-induced EMT, whereas direct inhibition of autophagy using 3-methyladenine (3-MA) (2 mM) or autophagy-related gene 5 (ATG5) gene silencing decreased the TGF-β1-induced EMT in HPMCs. These results suggest that autophagy could serve as a therapeutic target for the prevention of peritoneal fibrosis in patients undergoing peritoneal dialysis.

Fig. 1. TGF-β1 induces EMT and ROS generation in HPMCs (Oh, Se-Hyun, et al. 2024).

Fig. 2. NOX4 inhibition downregulates TGF-β1-induced autophagy and EMT in HPMCs (Oh, Se-Hyun, et al. 2024).

Human Omental Mesothelial Cells Exhibit a Corneal Endothelial-Like Cell Phenotype

To evaluate whether cultured human omental mesothelial cells (OMC) exhibit phenotypic and functional similarities to human corneal endothelial cells (CEC) and whether they can adhere to the corneal stroma and form a biomimetic corneal endothelium when grown on a human anterior lens capsule (HALC).

Human OMC were isolated from the greater omentum. Human B4G12 CEC were used as a reference for native and functional CEC phenotype whereas human mesenchymal stromal cells (MSC) served as a phenotypically distinct control group. OMC, CEC and MSC were compared using flow cytometry, immunofluorescence and qRT-PCR for lineage-specific markers, as well as through a transepithelial permeability assay. The adhesion capacity of OMC was also evaluated on both mouse corneal stroma and a decellularized HALC.

The results demonstrate that cultured human OMC exhibit phenotypic and functional similarities to CEC. The ability of OMC to adhere to the corneal stroma and to generate a biomimetic corneal endothelium when combined with HALC highlights their potential use in corneal endothelial regeneration.

Fig. 3. OMC and CEC display high similarities in their immunoexpression patterns and gene expression levels of simple epithelium and corneal endothelium markers (Alió, Jorge L., et al. 2025).

Fig. 4. HALC seeded with OMC creates a corneal endothelium biomimetic (Alió, Jorge L., et al. 2025).