A preparation method of a circular RNA molecule sponge drug

Abstract

The embodiment of the application relates to the technical field of biological medicine, and provides a preparation method of a circular RNA molecule sponge drug, which comprises the following steps: introducing a deletion and a mismatch in the reverse complementary sequence of a specific pathogenic miRNA to generate a protruding binding fragment with anti-cleavage characteristics; inserting the protruding binding fragment in series through a spacer sequence into a skeleton based on an endogenous circRHOBTB3 to obtain a recombinant circRNA expression plasmid; introducing the recombinant circRNA expression plasmid into a production cell line, and jointly introducing an exosome yield enhancement plasmid, and further introducing a transmembrane protein carrier for fusing and expressing a specific target polypeptide, so that the secreted exosome has specific tissue or cell targeting delivery capability; collecting exosome-free serum culture supernatant, and performing differential centrifugation and ultracentrifugation purification extraction to obtain an engineered exosome nanodrug; and adopting a circular RNA to replace a traditional linear nucleic acid structure, so that the structural stability of the molecule is significantly improved, and the in-vivo half-life of the drug is prolonged.

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