Fluorescence-Based Mono- and Multimodal Imaging for In Vivo Tracking of Mesenchymal Stem Cells

Application of Mesenchymal Stem Cells in Female Infertility Treatment: Protocols and Preliminary Results

Infertility is a global phenomenon that impacts people of both the male and the female sex; it is related to multiple factors affecting an individual's overall systemic health. Recently, investigators have been using mesenchymal stem cell (MSC) therapy for female-fertility-related disorders such as polycystic ovarian syndrome (PCOS), premature ovarian failure (POF), endometriosis, preeclampsia, and Asherman syndrome (AS). Studies have shown promising results, indicating that MSCs can enhance ovarian function and restore fertility for affected individuals. Due to their regenerative effects and their participation in several paracrine pathways, MSCs can improve the fertility outcome. However, their beneficial effects are dependent on the methodologies and materials used from isolation to reimplantation. In this review, we provide an overview of the protocols and methods used in applications of MSCs. Moreover, we summarize the findings of published preclinical studies on infertility treatments and discuss the multiple properties of these studies, depending on the isolation source of the MSCs used.

Perovskites as Multiphoton Fluorescence Contrast Agents for In Vivo Imaging

Multiphoton fluorescence microscopy is a powerful tool for imaging and exploring biological tissue at subcellular spatial resolution while minimizing photobleaching and autofluorescence. For optimal performance in multiphoton microscopy, materials exhibiting a large multiphoton absorption cross section (σn) and fluorescence quantum yield are desired. Notably, perovskite nanocrystals (CsPbX3, PNCs) exhibit exceptionally large two-, three-, up to five photon absorption cross section (σ2 ∼ 106 GM, σ3 ∼ 10-73 cm6s2 photon-2, σ5 ∼ 10-136 cm10s4 photon-4), along with near unity fluorescence quantum yield, making them desirable for deep tissue applications. Here, we employed PNCs as contrast agents to image mesenchymal stromal cells in a living mouse. The PNCs were stabilized by encapsulating them in a SiO2 matrix (∼60-70 nm in diameter), offering versatility for subsequent surface modification to target specific biological entities for both diagnostic and therapeutic applications. Multiphoton imaging of PNCs offers substantial benefits for dynamic tracking of cells in deep tissue, such as in understanding immune cell migration and other biological processes in both healthy and diseased tissues.

Dual/Multi-Modal Image-Guided Diagnosis and Therapy Based on Luminogens with Aggregation-Induced Emission

The combination of multiple imaging methods has made an indelible contribution to the diagnosis, surgical navigation, treatment, and prognostic evaluation of various diseases. Due to the unique advantages of luminogens with aggregation-induced emission (AIE), their progress has been significant in the field of organic fluorescent contrast agents. Herein, this manuscript summarizes the recent advancements in AIE molecules as contrast agents for optical image-based dual/multi-modal imaging. We particularly focus on the exceptional properties of each material and the corresponding application in the diagnosis and treatment of diseases.