Stem cells exosomes

Mesenchymal stem cell-derived EVs attenuate cartilage injury

The main strategy of tissue repair and regeneration focuses on the application of mesenchymal stem cells (MSCs) and cell-based nanoparticles, but there are still multiple challenges that may have negative impacts on human safety and therapeutic efficacy. Cell-free nanotechnology can effectively overcome these obstacles and limitations. MSC-derived natural small extracellular vesicles (sEVs) represent ideal nanotherapeutics due to their low immunogenicity and lack of tumorigenicity. Here, sEVs harvested from Whartons jelly mesenchymal stem cells (WJMSCs) were identified. In vitro results showed that WJMSC-sEVs efficiently entered chondrocytes in the osteoarthritis (OA) model, promoting chondrocyte migration and proliferation and modulating immune reactivity. In vivo, WJMSC-sEVs notably promoted chondrogenesis, which was consistent with the effect of WJMSCs. RNA sequencing results revealed that sEV-microRNA-regulated biocircuits can significantly contribute to the treatment of OA, such as by promoting the activation of the calcium signaling pathway, ECM-receptor interaction pathway and NOTCH signaling pathway.

Figure 1. Comprehensive characterization of WJMSCs-sEVs

The Flow NanoAnalyzer characterizes sEV size distribution, particle concentration and surface proteins at the single particle level, laying the foundation for the application of stem cell-derived exosomes for tissue repair and regeneration.

Int J Pharm., 2022, 623:121952.

Embryonic Stem Cell Exosomes for the Treatment of Malignant Glioma

Glioblastoma (GBM) is the most common primary malignant tumor of the central nervous system with high mortality and disability rate. High drug resistance of GBM along with limited delivery of chemotherapy drugs due to limitations arising from crossing the blood-brain barrier (BBB) reduces efficacy of treatment and predicts poor diagnosis. There is an urgent need to develop new drugs which can cross the BBB, thereby achieving effective treatment of GBM. In previous studies, researchers have worked on developing synthetic drug delivery systems to enable effective delivery across biological barriers. However, the challenge of nanocarriers to traverse the BBB has not been fully resolved, additionally the nanocarriers can themselves induce biotoxicity.

The study showed that embryonic stem cells (ESCs) derived exosomes (ESC-exos) have inhibitory effects on glioma cells and can be enabled to target tumor tissues by the modification of the exosomes (cRGDyK peptide modified). At the same time, paclitaxel (PTX) is added to the exosomes to improve the ability of exosomes to resist glioma, providing new ideas for the treatment of malignant glioma and other types of tumor diseases.

Figure 1. The size distribution of ESC-exos.

Figure 2. ESC-exos inhibits the activity of glioma cell.

Figure 3. The size distribution of cRGD-Exo-PTX and Exo-PTX.

Figure 4. Apoptosis of glioma cells treated with PTX and different types of ESC-exos.

The Flow NanoAnalyzer has the capability to determine whether the exosomes have been successfully modified and/or loaded with therapeutic drugs, as well as further evaluate the loading efficiency of drugs.