The success of mRNA
vaccines during the COVID-19 pandemic has greatly
accelerated the development of mRNA therapy. mRNA is a negatively
charged nucleic acid that serves as a template for protein synthesis
in the ribosome. Despite its utility, the instability of mRNA requires
suitable carriers forin vivodelivery. Lipid nanoparticles
(LNPs) are employed to protect mRNA from degradation and enhance its
intracellular delivery. To further optimize the therapeutic efficacy
of mRNA, site-specific LNPs have been developed. Through local or
systemic administration, these site-specific LNPs can accumulate in
specific organs, tissues, or cells, allowing for the intracellular
delivery of mRNA to specific cells and enabling the exertion of local
or systemic therapeutic effects. This not only improves the efficiency
of mRNA therapy but also reduces off-target adverse effects. In this
review, we summarize recent site-specific mRNA delivery strategies,
including different organ- or tissue-specific LNP after local injection,
and organ-specific or cell-specific LNP after intravenous injection.
We also provide an outlook on the prospects of mRNA therapy.