Multilayered polyelectrolyte assemblies as delivery system for biomedical applications

Abstract Gene therapy is a rapidly developing medical field, which focuses on the utilization of therapeutic delivery of recombinant nucleic acids into a patient’s cells to treat or prevent a broad spectrum of diseases. However, several important obstacles remain before its wide introduction into clinical application can be implemented. One of the biggest bottlenecks is a lack of efficient and safe delivery technologies, particularly, for in vivo distribution. Additionally, standard requirements for carriers are still an open question (safety, minimal/absent toxicity and immunogenicity, sufficient packaging capacity, targeting, straight and low-cost large-scale Good Manufacturing Practice (GMP) production). Therefore, a growing variety of non-viral delivery platforms represent a promising alternative. Nanotechnology opens new possibilities for resolving biomedical issues. Polymer and hybrid micro- and core–shell nanoparticles are currently under development as a platform for safe and efficient gene delivery. The present thesis describes the development of new safety gene delivery system based on polymer nanoparticles. The results show that nucleic acids (DNA/RNA) can be successfully imbedded into the nanoparticle structures and delivered to various types of cells. For the characterization of the biocompatibility of nanoparticles in vitro, two optical methods were considered. Compatibility with red blood cells (important for intravenous delivery) was assessed using optical tweezers. Capsule biodistribution in vivo was studied with fluorescence spectroscopy and a radiolabeling technique. The data and experience gained from this research open new prospects in the fields of delivery systems areas, gene therapy, and diagnostics in vivo and new possibilities for future clinical applications.Tiivistelmä Geeniterapia on nopeasti kehittyvä lääketieteellinen ala, joka keskittyy rekombinanttisten nukleiinihappojen terapeuttisen annon hyödyntämiseen potilaan soluihin laajan kirjon tautien hoitamiseksi tai ehkäisemiseksi. On kuitenkin olemassa useita tärkeitä esteitä, ennen kuin sen laajaa käyttöönottoa kliinisessä sovelluksessa voidaan toteuttaa. Yksi suurimmista pullonkauloista on tehokkaiden ja turvallisten jakelutekniikoiden puute etenkin in vivo -jakelussa. Myös kiistanalainen vakiovaatimukset operaattoreille ovat edelleen avoin ongelma (turvallisuus, vähäinen / puuttuva myrkyllisyys ja immunogeenisuus, riittävä pakkauskapasiteetti, kohdennus, suora ja edullinen laajamittainen GMP-tuotanto). Siksi kasvava valikoima ei-viraalisia jakelualustoja on lupaava vaihtoehto. Nanoteknologia avaa uuden mahdollisuuden ratkaista biolääketieteelliset kysymykset. Polymeerisiä ja hybridimikro- ja ydin-kuori-nanohiukkasia kehitetään parhaillaan turvallisen ja tehokkaan geeninsiirron alustana. Tässä opinnäytetyössä kuvataan polymeerisiin nanohiukkasiin perustuvan uuden turvallisuusgeenin kuljetusjärjestelmän kehittäminen. Tulokset osoittivat, että nukleiinihapot (DNA / RNA) voidaan upottaa onnistuneesti nanohiukkasten rakenteeseen ja toimittaa erityyppisiin soluihin. Nanohiukkasten biologisen yhteensopivuuden in vitro karakterisoimiseksi otettiin huomioon kaksi optista menetelmää. Yhteensopivuus punasolujen kanssa (tärkeä laskimoon annettaessa) arvioitiin optisilla pinseteillä. Kapselien biologinen jakautuminen in vivo mitattiin ja tutkittiin fluoresenssispektroskopialla ja radioleimaustekniikalla. Tästä tutkimuksesta saadut tiedot ja kokemukset avaavat uusia näkymiä jakelujärjestelmiin, geeniterapiaan ja diagnostiikkaan in vivo ja avaavat uusia mahdollisuuksia tulevassa kliinisessä sovelluksessa

Combined use of optical tweezers and scanning electron microscopy to reveal influence of nanoparticles on red blood cells interactions

Abstract As a promising drug delivery system, itself or coupled with red blood cells (RBC), nanoparticles (NP) should be studied in frames of their interaction at the cellular level. Experiments were performed on RBC in autologous blood plasma incubated with different NP — TiO₂, ZnO, nanodiamonds and polymeric nanocapsules. RBC aggregates formation in RBC suspension was observed with conventional microscopy, while quantitative interaction force measurements between individual RBC was assessed with optical tweezers. Scanning electron microscopy (SEM) imaging demonstrated NP localization and RBC membrane modifications upon binding with NP. Among tested NP, nanodiamonds caused increasing the size of aggregates in RBC suspensions, RBC interaction force increase and strong membrane surface modifications, comparing to other tested NP and control sample. Nanocapsules do not cause any adverse effects on RBC properties, confirming biocompatibility and applicability for drug delivery purposes. Optical tweezers combined with SEM imaging serves as fast informative assessment of NP effects on RBC

Biodegradable nanocarriers resembling extracellular vesicles deliver genetic material with the highest efficiency to various cell types

Abstract Efficient delivery of genetic material to primary cells remains challenging. Here, efficient transfer of genetic material is presented using synthetic biodegradable nanocarriers, resembling extracellular vesicles in their biomechanical properties. This is based on two main technological achievements: generation of soft biodegradable polyelectrolyte capsules in nanosize and efficient application of the nanocapsules for co‐transfer of different RNAs to tumor cell lines and primary cells, including hematopoietic progenitor cells and primary T cells. Near to 100% efficiency is reached using only 2.5 × 10–4 pmol of siRNA, and 1 × 10–3 nmol of mRNA per cell, which is several magnitude orders below the amounts reported for any of methods published so far. The data show that biodegradable nanocapsules represent a universal and highly efficient biomimetic platform for the transfer of genetic material with the utmost potential to revolutionize gene transfer technology in vitro and in vivo