Messenger RNA vaccines have shown their value for a broad range of therapeutic applications, ranging from cancer immunotherapy to infectious diseases. Additionally, vigorous efforts are now being devoted to the use of IVT mRNA technology for other uses such as cell therapy and gene editing. While these mRNA-based approaches show great promise as next-generation therapeutics, there are still many open questions about the effect of mRNA impurities that can occur during the IVT reactions.

In this Analytical Chemistry paper, the Genentech group used IVT-ready linearized ENFINIA DNA templates synthesized with 3 sizes of PolyA tail lengths (90, 110, 160 nt) as a starting IVT material for eGFP production to study the length effect on translation efficiency and stability. On day 1 the construct with 160 PolyA showed a higher percentage of cells expressing eGFP than the those with shorter tails, demonstrating a positive correlation between PolyA tail length and protein expression.