Investigation of composition, properties and production procedure of nanodelivery systems for mRNA-based vaccines

Cepiva na osnovi informacijske RNA (mRNA) predstavljajo obetavno platformo v boju proti virusnim okužbam in v imunoterapiji raka. Nanodostavni sistemi imajo pomembno vlogo v mRNA-cepivih, saj omogočajo vnos mRNA v celice in lahko delujejo kot adjuvansi. Namen te magistrske naloge je bil na podlagi razpoložljivih literaturnih virov proučiti sestavo, tehnologijo izdelave in lastnosti nanodostavnih sistemov, ki omogočajo vnos mRNA-cepiv. Ugotovili smo, da so v izbranih raziskavah proučevali štiri vrste nanodostavnih sistemov za vnos mRNA-cepiv, in sicer lipidne, polimerne, peptidne ter hibridne nanodostavne sisteme. Primerjali smo njihovo sestavo, velikost, porazdelitev velikosti, površinski naboj, učinkovitost vgrajevanja mRNA in imunski odziv, ki ga sprožijo in vitro ali in vivo. Ugotovili smo, da so se v raziskavah najpogosteje pojavili lipidni nanodostavni sistemi, natančneje lipidni nanodelci. Večina nanodostavnih sistemov je imela ozko porazdelitev velikosti delcev. Vsi prazni nanodostavni sistemi so imeli pozitiven površinski naboj, po vgrajevanju mRNA pa se je njihov površinski naboj zmanjšal, kar je vodilo v fizikalno manj stabilne formulacije. Rezultati transmisijske elektronske mikroskopije so pokazali, da so bili vsi nanodostavni sistemi sferične oblike z ozko porazdelitvijo velikosti. Vse formulacije so sprožile močne imunske odzive in vivo ali in vitro, kar kaže njihov potencial za uporabo v mRNA-cepivih. Na podlagi pregleda literature smo zaključili, da so glede na lastnosti najbolj obetavni za uporabo v mRNA-cepivih lipidni nanodostavni sistemi, saj so stabilni, varni, zahtevajo relativno nizke stroške izdelave in so tudi najbolj raziskovani.Messenger RNA (mRNA)-vaccines offer a promising new approach in infectious diseases prevention and cancer immunotherapy. Nanodelivery systems play an important role in mRNA vaccines, since they enable intracellular delivery of mRNA and can act as adjuvants. The aim of our research was to investigate composition, production procedure and properties of nanodelivery systems for mRNA vaccines. The method we used was a systematic review of scientific research articles. The most widely investigated delivery systems for mRNA were lipid, polymer, peptide and hybrid lipid–polymer nanodelivery systems. We compared their compositions, particle sizes and size distributions, surface charges, encapsulation efficiencies and induced immune responses in vitro or in vivo. The most frequently investigated were lipid-based nanodelivery systems, specifically lipid nanoparticles. Size distribution of the majority of investigated nanodelivery systems was uniform. Empty nanodelivery systems showed a positive surface charge, after incorporation of negatively charged mRNA, their zeta potential decreased, which resulted in less physical stable formulations. Transmission electron microscopy showed spherical morphology of all investigated nanodelivery systems and their narrow size distribution. Some lipid nanoparticles had multilamellar structure and some had defects in their internal structure. All formulations induced strong immune responses in vivo or in vitro, showing a potential for mRNA vaccine delivery. On the basis of a literature review, we concluded that lipid-based nanoparticles are the most promising delivery systems for application in mRNA-based vaccines, because they are considered safe, stable, low-cost and are currently most frequently researched nanodelivery systems