Certainly! Vaccine delivery systems are the means by which the immune-stimulating agent constituting the vaccine is packaged and administered into the human body to ensure that the vaccine reaches the desired tissue ². There are several types of vaccine delivery systems, including **oral**, **subcutaneous**, and **intramuscular** injections, as well as **mucosal** vaccines applied to surfaces such as those lining the gut or nasal passages ².
In recent years, mRNA vaccines have gained popularity due to their simple production process, better safety profiles than DNA vaccines, and the ability of mRNA-encoded antigens to be readily expressed in cells ¹. However, mRNA vaccines also possess some inherent limitations, such as the risk of side effects like allergy, renal failure, heart failure, and infarction, as well as the potential for the vaccine mRNA to degrade quickly after administration or cause cytokine storms ¹. To overcome these challenges, appropriate carriers can be used to avoid degradation and enhance immune responses, effector presentation, biocompatibility, and biosafety ¹.
In terms of delivery systems for mRNA vaccines, they can be divided into viral- and non-viral vector delivery systems. This review mainly discusses non-viral vectors, which can be further subdivided into lipid or lipid materials and polymer delivery systems ¹.
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