Functionalization of rice husk-derived mesoporous silica nanoparticles for targeted and imaging in cancer drug delivery.

BACKGROUND: Rice, a pivotal global food staple, annually accumulates vast amounts of rice husks, resulting in substantial environmental impact. Exploiting the high silica content in rice husk, our research aimed to recycle this agricultural byproduct to synthesize mesoporous silica nanoparticles (rMSNs). These nanoparticles were further modified to evaluate their potential as effective carriers for cancer drug delivery. RESULTS: rMSNs showed high biocompatibility, large surface area and porous structure as MSNs, making them excellent drug carriers. Further modifications were applied to rMSNs, such as the incorporation of the lanthanides europium and gadolinium into rMSNs, making them fluorescent and magnetic for detection and tracking using confocal fluorescence microscopy and magnetic resonance imaging. Additionally, folic acid and aptamer AS1411 were conjugated with rMSNs to enhance the targeting of cancer cells. HeLa cells exhibited higher uptake of camptothecin (CPT)-loaded rMSNs compared to normal fibroblast cells (L929). The linkage of disulfide bonds to rMSNs also allowed CPT to be carried by rMSNs and released intracellularly in the presence of the abundant reducing agent glutathione. The validation of rMSNs in vitro and in vivo proved their practical feasibility. CONCLUSION: Our findings indicate that low-cost rMSNs, derived from recycled agricultural waste, can replace highly valuable MSNs. Functionalized rMSNs exhibit promising capabilities in transporting clinical drugs to specific aberrant tissues and offering dual-targeting and dual-imaging functionalities for enhanced cancer therapy. © 2023 Society of Chemical Industry.

Using marker gene analysis instead of mixed lymphocyte reaction assay for identification of functional CD4+FOXP3+ regulatory T cells.

OBJECTIVE: To establish a quick analytical method using quantitative PCR for marker gene analysis to identify the functions of iTreg cells and subsequently curtail the harvest time for iTreg cells. RESULTS: The data from the marker gene analysis indicated that varying proportions of iTreg cells could reveal the various expression levels of these genes. FoxP3 expression increased to a considerable degree. By using the same iTreg population, the mixed lymphocyte reaction assay was conducted for 5 days. The suppression percentage of T-cells was dependent on the proportion of iTreg cells, indicating that gene expression levels can represent the biological functions of iTreg cells. By using human peripheral blood mononuclear cells for Treg cell induction, the marker gene expression analysis showed a difference between iTreg cells and uninduced T cells. CONCLUSION: Marker gene analysis requires only 1 day to identify the functions of human iTreg cells can save time in clinical application and might prevent graft-versus-host disease occurrence effectively.