Organosilica Cages Target Hepatic Sinusoidal Endothelial Cells Avoiding Macrophage Filtering.

Over the last years, advancements in the use of nanoparticles for biomedical applications have clearly showcased their potential for the preparation of improved imaging and drug-delivery systems. However, compared to the vast number of currently studied nanoparticles for such applications, only a few successfully translate into clinical practice. A common "barrier" that prevents nanoparticles from efficiently delivering their payload to the target site after administration is related to liver filtering, mainly due to nanoparticle uptake by macrophages. This work reports the physicochemical and biological investigation of disulfide-bridged organosilica nanoparticles with cage-like morphology, OSCs, assessing in detail their bioaccumulation in vivo. The fate of intravenously injected 20 nm OSCs was investigated in both healthy and tumor-bearing mice. Interestingly, OSCs exclusively colocalize with hepatic sinusoidal endothelial cells (LSECs) while avoiding Kupffer-cell uptake (less than 6%) under both physiological and pathological conditions. Our findings suggest that organosilica nanocages hold the potential to be used as nanotools for LSECs modulation, potentially impacting key biological processes such as tumor cell extravasation and hepatic immunity to invading metastatic cells or a tolerogenic state in intrahepatic immune cells in autoimmune diseases.