Peptide barcode method efficiently screens mRNA expression control sequences for targeted therapeutics

Precise control over specific protein expression in target cells is a critical challenge for advancing messenger RNA (mRNA) therapeutics. While incorporating regulatory sequences, such as microRNA-responsive RNA switches, offers a promising avenue for cell-type-specific targeting, optimizing these sequences is often bottlenecked by extensive, time-consuming screening using conventional evaluation methods. This gap hinders the rapid development of highly specific and effective mRNA-based treatments, necessitating more efficient high-throughput screening tools.

Researchers developed a multiplexed evaluation methodology utilizing peptide barcodes coupled with liquid chromatography-mass spectrometry (LC-MS) to enhance the screening efficiency of mRNA expression control sequences. They designed various mRNAs, each equipped with distinct cell-specific expression control sequences, and fused unique peptide barcodes to their encoded target proteins. The study compared conventional individual transfections against simultaneous co-transfections of these barcoded mRNAs. Protein expression derived from individual mRNA candidates within a single mixed sample was then quantified using the LC-MS-based method.

The novel LC-MS-based method successfully distinguished and quantified protein expression originating from individual mRNA candidates within a single, mixed sample. This demonstrated the method's capability for multiplexed analysis. Importantly, the simultaneous evaluation using peptide barcodes yielded results that were equivalent to those obtained from conventional individual evaluations. This equivalence was achieved while requiring a significantly reduced number of samples, highlighting a substantial improvement in efficiency. The abstract does not provide specific numerical data (e.g., percentages, p-values, fold-changes) but emphasizes the qualitative success and efficiency gains. This multiplexed technology is poised to accelerate the screening process for regulatory sequences, thereby enhancing the development of mRNA therapeutics with high targeting specificity.

The simultaneous evaluation using peptide barcodes yielded results equivalent to the individual evaluations but required a reduced number of samples.