Tomsk Polytechnic University is studying a technology of targeted drug delivery. In the recent paper published in Advanced Healthcare Materials (IF 5.11; Q1) the researchers from the School of Chemistry & Biomedical Studies reviewed the most recent advances in living cell-based drug vehicles to deliver biologically active compounds and reported the outcomes of their experiments. The utilization of living cells as ‘Trojan horses’ for drug transport will reduce toxic impact of substances on health tissues of the body.
In the article, the scientists consider blood cells, i.e. leukocytes and neutrophilic leukocytes, erythrocytes and platelets, as well as stem cells as drug transporters. The cells are carriers for nanocapsules containing required therapeutics. TPU scientists synthesize capsules based on biodegradable polymers, e.g. polypeptides and polysaccharides. Living cells and nanocapsules are connected by several pathways, including covalent conjugation, the interaction of cells with carriers via antibodies and internalization when cells absorb capsules.
Now research teams from various countries are engaged in the development of targeted drug delivery. Indeed, their methods have not been introduced into medical practice yet. Scientists are just searching for the most effective and nontoxic methods. TPU team has already conducted a lot of research and synthesis of nanocapsules which are suitable for drug delivery.
Alexander Timin, a research engineer of the School of Chemistry & Biomedical Studies says:
‘We consider the utilization of living cells as ‘Trojan horses’ transporting nanocapsules as one of the most promising drug delivery methods. Due to natural mechanisms they can reach inflammatory forci and tumors in the body so the drug affects the damaged cells. This is especially true for cancer diseases treated with toxic drugs that affect healthy tissues.’
Photo: Scheme for cell-based nanoparticle drug delivery. Cells loaded with nanoparticles are intravenously reinjected into the circulation. Cells carry the nanoparticles across the blood vessel barrier to the inflammation site. Therapeutic nanoparticles are then released from the carrier cell at the inflammation site.
Controlling such nanocapsules in order they release drugs in a proper place and at a proper time is possible using ultrasound, light or alternating magnetic field. TPU scientists also develop such technologies.
‘The selection of a drug is largely determined by the type of a carrier. Generally, we can load any low-molecular compound which represents antineoplastic and antimicrobial preparations, as well as high-molecular compounds which are genetic materials, for example, in the form of single-stranded RNAs, matrix RNAs and DNAs,’ explains the scientist. ‘After encapsulating biologically active substances inside microcarriers, we incubate our carriers with cells within 24h that causes particle internalization by the cells. After that, we may administrate cells with capsules into the body where the cells should migrate to the forci of tumor or inflammation. Further we can remotely impact on the affected forci to release drugs in the designated area.’
As TPU experiments showed, lymphocytes, including neutrophils, and stem cells act as the most efficient transporters. TPU researchers investigate stem cells jointly with R.M. Gorbacheva Research Institute for Children’s Oncology, Hematology and Transplantology.