Abstract: Osteopenia, a concern in aging and congenital disorders (1), involves Mmp14, a matrix metalloproteinase crucial for the transition from chondrocytes to osteoblasts. Ablating Mmp14 in mice increased trabecular bone, enhancing PTH impact on osteoblastogenesis (2). Inhibiting MMP14 may be a potential therapeutic strategy for osteopenia. Antisense oligonucleotides (ASO), a common gene knockdown therapy, modify gene expression and mRNA splicing in genetic disorders (3). Stabilization strategies, like self-assembled DNA nanostructures, aid intracellular delivery. Combining aptamers with DNA nanostructures addresses several limitations, allowing specific targeting of molecules, surfaces, and cells (4). Herein, this study is aiming to develop a self-assembled DNA nanostructure as a carrier of gene silencing therapeutics targeting osteoblasts for bone and cartilage. We have identified a single-stranded DNA (ssDNA) aptamer, Apt15 targeting osteoblasts through cell-SELEX and high-throughput sequencing, utilizing the MC3T3-E1 cell line as the target and the ATDC-5 chondrocyte cell line as the control. It demonstrated nanomolar-range dissociation constants (Kd values), displaying robust binding affinity and selectivity under physiological conditions. Directly incorporated Apt15 to DNA nanostructures significantly improved its cellular delivery efficiency and also facilitate target delivery with less off-target effect. This study presents a promising approach for delivering gene silencing therapeutic agents specifically to osteoblasts, and it broadens the potential use of DNA nanotechnology in precise drug delivery.
Funding Source: This work was partially HMRF fund, grant number 09202246
