Provided nucleic acid-based expression construct for the target cell-specific production of a therapeutic protein, such as a pro-apoptotic protein, within a target cell, including a target cell that is associated with aging, disease, or other condition, in particular a target cell that is a senescent cell or a cancer cell. Also provided are formulations and systems, including fusogenic lipid nanoparticle (LNP) formulations and systems, for the delivery of nucleic acid-based expression constructs as well as methods for making and using such nucleic acid-based expression constructs, formulations, and systems for reducing, preventing, and/or eliminating the growth and/or survival of a cell, such as a senescent cell and/or a cancer cell, which is associated with aging, disease, or other condition as well as methods for the treatment of aging, disease, or other conditions by the in vivo administration of a formulation, such as a fusogenic LPN formulation, comprising an expression construct for the target cell-specific production of a therapeutic protein, such as a pro-apoptotic protein, in a target cell that is associated with aging, disease, or other condition, in particular a target cell that is a senescent cell or a cancer cell.

A modified cytidine compound, that is, an aminooxy group is modified at the 4-position of a cytidine pyrimidine ring to produce derivative cytidine and nucleic acid containing the derivative cytidine, such as RNA. The expression level of the nucleic acid containing the modified cytidine, in particular mRNA, in the body is significantly improved.

A modified cytidine compound, that is, an aminooxy group is modified at the 4-position of a cytidine pyrimidine ring to produce derivative cytidine and nucleic acid containing the derivative cytidine, such as RNA. The expression level of the nucleic acid containing the modified cytidine, in particular mRNA, in the body is significantly improved.

Provided are methods of making and delivering vaccine compositions using an enucleated cell-based platform. Methods of clearing pathogenic infections in a subject using the enucleated cell-based platform is also provided. Such enucleated cell-based platform reduces the vaccine development timeline as compared with conventional biological vaccines, and improves vaccine efficacy.

Provided are methods of making and delivering vaccine compositions using an enucleated cell-based platform. Methods of clearing pathogenic infections in a subject using the enucleated cell-based platform is also provided. Such enucleated cell-based platform reduces the vaccine development timeline as compared with conventional biological vaccines, and improves vaccine efficacy.

Methods are provided for transfecting cells with large cargo using a poly(beta-amino ester) (PBAE) molecule, and achieving high efficiency and viability. A method is provided of transfecting cells with a cargo, by forming a complex of the cargo with a (PBAE) molecule, mixing the complex with a first buffer and contacting the complex with the cells, wherein the cargo has a dimension of at least 0.1 μm. The PBAE molecule may be formed by reacting an amine with a di(acrylate ester). In some aspects, the PBAE molecule is poly(1,4-butanediol diacrylate-co-4-amino-1-butanol). In some aspects, the PBAE molecule is capped with 1-(3-aminopropyl)-4-methylpiperazine.

The present invention provides extrcellular vesicles, such as exosomes, engineered to be loaded with miR-345, which may be further loaded with, e.g., miR-146a and let-7b, and/or further be depleted of miR-10a and/or miR-10b. The present invention also provides an assay method, wherein the amounts of miR-345, miR146a, and let-7b in a sample of extracellular vesicles are positively associated with potency, and wherein the amount of miR-10b in a sample of extracellular vesicles is negatively associated with potency.

The present invention provides extrcellular vesicles, such as exosomes, engineered to be loaded with miR-345, which may be further loaded with, e.g., miR-146a and let-7b, and/or further be depleted of miR-10a and/or miR-10b. The present invention also provides an assay method, wherein the amounts of miR-345, miR146a, and let-7b in a sample of extracellular vesicles are positively associated with potency, and wherein the amount of miR-10b in a sample of extracellular vesicles is negatively associated with potency.

Compositions and methods for gene editing. In some embodiments, a polynucleotide encoding Cas9 is provided that can provide one or more of improved editing efficiency, reduced immunogenicity, or other benefits.

Compositions and methods for gene editing. In some embodiments, a polynucleotide encoding Cas9 is provided that can provide one or more of improved editing efficiency, reduced immunogenicity, or other benefits.