Background Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition characterized by debilitating pelvic pain. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) are recognized as pivotal mediators of MSCs’ paracrine activity and represent a novel therapeutic approach for IC/BPS. However, their efficacy is hindered by the inherent variability of primary MSCs (pMSCs) from different donors and their susceptibility to senescence during culture expansion.Methods To overcome these challenges, we developed conditionally immortalized mesenchymal stem cells (iMSCs) using a doxycycline-regulated simian virus 40 Large T expression system in pMSCs. The conditioned proliferation capacity of iMSCs was evaluated using cell counting and immunocytochemistry. The expression of surface markers on iMSCs was assessed by flow cytometry. The osteogenic and adipogenic differentiation capabilities of iMSCs at different population doubling (PD) numbers were analyzed by qPCR, alizarin red staining, and oil red O staining. The EVs secreted by iMSCs were characterized using Western blot, scanning electron microscopy, and particle size analysis. In vitro and in vivo bladder inflammation models were used to evaluate the therapeutic effects of EVs on IC/BPS.Results These iMSCs exhibited precisely controlled proliferation, maintained surface marker expression and differentiation capacities, comparable to pMSCs up to PD 40. The characteristics of iMSC-EVs are equivalent to those of pMSCs. Furthermore, in vitro cellular experiments demonstrate that iMSC-EVs provide protective effects against LPS/ATP-induced damage in SV-HUC-1 cells. Additionally, administration of iMSC-EVs significantly enhanced tissue healing and anti-inflammatory capabilities in an IC/BPS animal model.Conclusion sIn summary, this approach produced a reliable source of functional MSCs and EVs, with iMSC-EVs demonstrating robust immunomodulatory properties and promoting tissue healing in IC/BPS. This method represents a promising alternative to pMSCs for IC/BPS therapy.
Background The gastrointestinal epithelium plays an important role in directing recognition by the immune system, and epithelial cells provide the host's front line of defense against microorganisms. However, it is difficult to cultivate avian intestinal epithelial cells in vitro for lengthy periods, and the lack of available cell lines limits the research on avian intestinal diseases and nutritional regulation. Chicken coccidiosis is a serious intestinal disease that causes significant economic losses in the poultry industry. In vitro, some cell line models are beneficial for the development of Eimeria species; however, only partial reproduction can be achieved. Therefore, we sought to develop a new model with both the natural host and epithelial cell phenotypes.Methods In this study, we use the SV40 large T antigen (SV40T) gene to generate an immortalized cell line. Single-cell screening technology was used to sort positive cell clusters with epithelial characteristics for passage. Polymerase chain reaction (PCR) identification, immunofluorescence detection, and bulk RNA sequencing analysis and validation were used to check the expression of epithelial cell markers and characterize the avian intestinal epithelial cell line (AIEC). AIECs were infected with sporozoites, and their ability to support the in vitro endogenous development of Eimeria tenella was assessed.Results This novel AIEC consistently expressed intestinal epithelial markers. Transcriptome assays revealed the upregulation of genes associated with proliferation and downregulation of genes associated with apoptosis. We sought to compare E. tenella infection between an existing fibroblast cell line (DF-1) and several passages of AIEC and found that the invasion efficiency was significantly increased relative to that of chicken fibroblast cell lines.Conclusion sAn AIEC will serve as a better in vitro research model, especially in the study of Eimeria species development and the mechanisms of parasite–host interactions. Using AIEC helps us understand the involvement of intestinal epithelial cells in the digestive tract and the immune defense of the chickens, which will contribute to the epithelial innate defense against microbial infection in the gastrointestinal tract.Graphical Abstract
危险品化学品经营许可证（带存储）