Protein-based nanoparticle for self-packaging and delivering mrna, preparation method thereof and pharmaceutical composition

A method for preparing protein-based nanoparticle for self-packaging and delivering mRNA, comprising:

• providing a first donor plasmid, a second donor plasmid and a third donor plasmid, wherein the first donor plasmid comprises a nucleocapsid protein gene and an envelope protein gene, the second donor plasmid comprises an engineered envelope protein gene, and the third donor plasmid comprises a target gene;
• performing a plasmid transposing step, wherein the first donor plasmid is transposed to a first shuttle vector, the second donor plasmid is transposed to a second shuttle vector, and the third donor plasmid is transposed to a third shuttle vector, wherein the first shuttle vector is transfected to a first virus-amplifying cell, the second shuttle vector is transfected to a second virus-amplifying cell, and the third shuttle vector is transfected to a third virus-amplifying cell;
• performing a recombinant virus preparing step, wherein the first virus-amplifying cell, the second virus-amplifying cell and the third virus-amplifying cell are cultured so as to obtain a first recombinant baculovirus, a second recombinant baculovirus and a third recombinant baculovirus, wherein the first recombinant baculovirus is obtained from the first virus-amplifying cell, the second recombinant baculovirus is obtained from the second virus-amplifying cell, and the third recombinant baculovirus is obtained from the third virus-amplifying cell;
• and
• performing a transducing step, wherein the first recombinant baculovirus, the second recombinant baculovirus and the third recombinant baculovirus are used to infect a producer cell so as to express a nucleocapsid protein, an envelope protein, an engineered envelope protein and a target RNA, and the nucleocapsid protein, the envelope protein, the engineered envelope protein and the target RNA are self-assembled so as to form a protein-based nanoparticle, and the protein-based nanoparticle is for self-packaging and delivering mRNA;
• wherein the protein-based nanoparticle comprises a lipid carrier, the nucleocapsid protein, the envelope protein, the engineered envelope protein and the target RNA, the target RNA and the nucleocapsid protein are located in the lipid carrier, the target RNA is covered by the nucleocapsid protein, and the envelope protein and the engineered envelope protein are separately located on a surface of the lipid carrier.