INNOVATIVE IN VITRO PLATFORMS FOR INVESTIGATING THERAPEUTIC EFFECTS AND BIO-DISTRIBUTION OF EXTRACELLULAR VESICLES
Authors:   , Nguyen Vy Vuong Tuong 
Published: September 2024

The global burden of kidney diseases is immense, affecting millions of people worldwide and posing significant challenges to current treatment options such as dialysis and transplantation. This thesis explores the potential of regenerative medicine, particularly focusing on mesenchymal stromal cells (MSCs) and the extracellular vesicles (EVs) they produce, as a promising therapeutic option for kidney disease treatment.To harness the therapeutic potential of MSC-derived EVs,especially small EVs (sEV), it is essential to evaluate their efficacy through reliable functional assays. Chapter 2 reveals significant variability in the methods and results of these assays across different studies. By identifying a diverse range of functional assays used to assess EV properties—such as anti-inflammatory effects, tissue regeneration, and immunomodulation—it is illustrated clear that standardization is crucial. The chapter proposes a framework for harmonizing functional assays, emphasizing the need for consistent experimental design, controls, and reporting standards. Standardizing these assays ensures reliability and reproducibility, which are foundational for advancing MSC-sEVs towards clinical applications.Similarly, consistency in EV preparations is vital for their therapeutic use, and chapter 3 focuses on addressing this through standardized detailed MSC-EV surface protein profiling. Utilizing multiplex bead-based assays, a consistent set of surface proteins characteristic of MSC-sEVs—such as CD73, CD105 and CD44—is identified. The reproducibility of these assays across different laboratories around the world is demonstrated, ensuring high reliability. This standardized approach to characterizing EVs not only facilitates quality control but also supports the regulatory approval process by providing a reliable method for ensuring consistency in EV preparations.Advancing the evaluation of MSC-EVs requires sophisticated in vitro models. Chapter 4 reviewed the development of organoids and organ-on-a-chip systems, which replicate human tissue architecture and function. These advanced models are shown to be effective in drug testing and disease modeling, offering more accurate predictions of human responses than traditional cell cultures or animal models. The integration of stem cell-derived organoids into organ-on-a-chip systems creates complex, physiologically relevant platforms. These models facilitate personalized drug testing and disease research, providing ethical alternatives to animal testing and paving the way for personalized medicine approaches.Building on the advancements in in vitro models, in chapter 5, we introduce a multi-organ-on-a-chip system that integrates kidney and liver organoids. This innovative model effectively mimics human organ systems, allowing for comprehensive evaluation of MSC-sEVs. Detailed insights into the biodistribution of these vesicles and their therapeutic effects, such as reducing tissue damage and promoting tissue regeneration, are provided. The ability to replicate systemic interactions and physiological responses within this model offers a powerful tool for translational research, bridging the gap between preclinical studies and clinical applications.The potential of organ-on-a-chip models to enhance renal research is significant, offering valuable insights that are difficult to obtain from traditional models.Chapter 6 provides a systematic review of kidney-on-a-chip models, highlighting their significant advancements and applications. These models have improved replication of renal architecture and function, proving effective in studying renal physiology, pathophysiology, drug testing, and disease modeling. Despite ongoing challenges, such as scalability and complexity, the utility of these models in understanding kidney diseases and testing therapeutic