Biomimetic drug delivery platforms based on mesenchymal stem cells impregnated with light-responsive submicron sized carriers.

Synthetic organic and inorganic carriers often have limitations associated with problematic targeting ability or non-optimized pharmacokinetics, and, therefore, they have restricted therapeutic potential. Natural drug carriers (e.g. mesenchymal stem cells, MSCs) are able to migrate towards the tumor site and penetrate cancerous cells. These biomimetic features make MSCs an attractive delivery platform that allows achieving maximal therapeutic efficiency with minimal toxic side effects. A combination of MSCs exhibiting a homing effect on tumors with stimuli-responsive nanostructured carriers is foreseen to have a huge impact in the field of personalized oncology. Here we develop for the first time a light-sensitive biomimetic delivery platform based on MSCs impregnated with submicron sized composite capsules containing an antitumor drug. This cell-based delivery system triggers the release of the drug upon near-infrared (NIR) laser irradiation due to gold nanorods (Au NRs) incorporated into the capsule wall. The NIR-triggered release of the antitumor drug such as vincristine leads to the effective mortality of tumor spheroids made of primary melanoma cells. Encapsulated vincristine delivered by MSCs into the tumor spheroids and deployed over the whole spheroid upon NIR exposure represents a promising therapy for the improved treatment of malignant neoplasms.