Live‐cell analysis of cell penetration ability and toxicity of oligo‐arginines

作者：Gisela Lättig-Tünnemann, Gohar Ter‐Avetisyan, Robert Montgomery Martin, Martin Thomas Stöckl, Andreas Herrmann, M. Cristina Cardoso · 发表于：Journal of Peptide Science · 年份：2007 · DOI：10.1002/psc.968 · 被引用次数：285 · 研究领域：RNA Interference and Gene Delivery、Advanced biosensing and bioanalysis techniques、Virus-based gene therapy research

Cell penetrating peptides (CPPs) are useful tools to deliver low-molecular-weight cargoes into cells; however, their mode of uptake is still controversial. The most efficient CPPs belong to the group of arginine-rich peptides, but a systematic assessment of their potential toxicity is lacking. In this study we combined data on the membrane translocation abilities of oligo-arginines in living cells as a function of their chain length, concentration, stability and toxicity. Using confocal microscopy analysis of living cells we evaluated the transduction frequency of the L-isoforms of oligo-arginines and lysines and then monitored their associated toxicity by concomitant addition of propidium iodide. Whereas lysines showed virtually no transduction, the transduction ability of arginines increased with the number of consecutive residues and the peptide concentration, with L-R9 and L-R10 performing overall best. We further compared the L- and D-R9 isomers and found that the D-isoform always showed a higher transduction as compared to the L-counterpart in all cell types. Notably, the transduction difference between D- and L-forms was highly variable between cell types, emphasizing the need for protease-resistant peptides as vectors for drug delivery. Real-time kinetic analysis of the D- and L-isomers applied simultaneously to the cells revealed a much faster transduction for the D-variant. The latter underlies the fact that the isomers do not mix, and penetration of one peptide doe...