High Expression of THY1 in Gallbladder Fibroblasts Promotes the Formation and Progression of Gallstones

Background THY1 (Thy-1 cell surface antigen) is a glycophosphatidylinositol (GPI)-anchored membrane glycoprotein involved in cell-cell interactions, tissue remodeling, and immune regulation. Initially studied in neural and immune cells, THY1 is increasingly recognized for its roles in inflammatory responses and fibrosis, processes that are central to gallstone formation. Methods We performed multi-omics analyses, including transcriptomics, proteomics, and single-cell sequencing, to investigate changes in the gallbladder during gallstone formation. A gallstone mouse model was established using a lithogenic diet, alongside a THY1 knockdown gallstone mouse model created via sh-RNA, to explore the role of THY1 in this process. Hematoxylin and eosin (HE) staining and quantitative reverse transcription PCR (qRT-PCR) were conducted to assess inflammation levels in THY1 knockdown mice during gallstone formation. Western blotting, immunohistochemistry, and immunofluorescence were employed to evaluate the expression of fibronectin (FN) and collagen I (COL-I), elucidating the role of THY1 in extracellular matrix (ECM) formation during gallstone progression. Additionally, biochemical assays were used to quantify bile acids, phospholipids, cholesterol, and triglycerides, and the cholesterol saturation index (CSI) was calculated to further analyze the biochemical environment. Results THY1 expression was significantly elevated in gallbladder fibroblasts during gallstone formation. Knockdown of THY1 alleviated gallstone formation induced by a lithogenic diet in mice. In THY1 knockdown mice, cholesterol levels in gallbladder bile were significantly reduced, bile acid concentration increased, and the CSI index decreased. Additionally, the expression of inflammatory cytokines in the gallbladders of THY1 knockdown mice was reduced, leading to decreased gallbladder inflammation. ECM formation in the gallbladders of THY1 knockdown mice was also alleviated. Conclusion This study reveals that high expression of THY1 in gallbladder fibroblasts promotes the progression of gallstones by increasing inflammation levels and ECM formation.