Regeneration of Elastin by Synthetic mRNA

Background: Elastin is a crucial extracellular matrix protein for the elasticity of tissues and organs, including the lungs, blood vessels, and skin. It is predominantly produced during the neonatal period, with its expression ceasing in adulthood. Consequently, the loss of elastin due to aging, disease, or injury can severely impair the function of tissues, such as arteries. The de novo expression of tropoelastin (TE) protein, the precursor to elastin, was evaluated both in vitro and ex vivo by delivering TE-encoding synthetic mRNA into different cell types and porcine skin. Further investigations were conducted in pigs after the application of TE mRNA to analyze the de novo synthesis of TE in vivo.

Methods: Codon optimization and nucleotide modification of TE mRNA were performed. After the in vitro transfection of the cells, cell viability was assessed using Presto Blue, and TE protein synthesis was detected by ELISA. Furthermore, hydrogels containing cells were generated to detect the effect of TE mRNA transfection on elastin synthesis. TE mRNA variants were administered intradermally into porcine skin, and resulting elastin production was detected using elastin-specific ElaNIR staining and an in vivo imaging system (IVIS).

Results: The codon optimization led to a significantly improved protein synthesis without affecting cell viability in vitro. Furthermore, nucleotide modifications of the mRNA enhanced translation efficiency and reduced cellular toxicity. After 3 to 7 days cultivation in hydrogels, an increased elastin production by the seeded cells was detected using elastin-specific antibody staining. In vivo, significantly increased protein expression was detected after the delivery of a codon-optimized TE mRNA variant with me1Ψ modification.

Conclusion: The administration of synthetic TE mRNA into the pig skin resulted in increased TE synthesis in vivo. Moreover, through codon optimization and nucleotide modification, an improved synthetic TE mRNA was obtained, resulting in improved TE protein synthesis. This TE mRNA holds potential for further applications in regenerating the elasticity of other tissues, such as blood vessels.

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Artikel online veröffentlicht:
11. Februar 2025