There are several challenges regarding the clinical use of mRNA. One challenge is that mRNA is inherently unstable and prone to degradation. This instability affects how mRNA vaccines are stored and delivered. Another challenge is that as a negatively charged molecule, mRNA has difficulty crossing the cell membrane on its own. Thus, delivering mRNA into cells also presents a significant challenge. To address these two issues, mRNA is often encapsulated in specialized delivery systems (e.g. lipid nanoparticles) to protect it and help it enter target cells effectively. Another limitation is that making enough mRNA for widespread use is difficult and costly because the process is complex. Lastly, mRNA can trigger immune responses in the body, which can lead to inflammation or other harmful reactions.