Targeted release of transcription factors for cell reprogramming by a natural micro-syringe

Publication date: 20 November 2016 Source:International Journal of Pharmaceutics, Volume 513, Issues 1–2 Author(s): Lionel Berthoin, Bertrand Toussaint, Frédéric Garban, Audrey Le Gouellec, Benjamin Caulier, Benoît Polack, David Laurin Ectopic expression of defined transcription factors (TFs) for cell fate handling has proven high potential interest in reprogramming differentiated cells, in particular for regenerative medicine, ontogenesis study and cell based modelling. Pluripotency or transdifferentiation induction as TF mediated differentiation is commonly produced by transfer of genetic information with safety concerns. The direct delivery of proteins could represent a safer alternative but still needs significant advances to be efficient. We have successfully developed the direct delivery of proteins by an attenuated bacterium with a type 3 secretion system that does not require challenging and laborious steps for production and purification of recombinant molecules. Here we show that this natural micro-syringe is able to inject TFs to primary human fibroblasts and cord blood CD34+ hematopoietic stem cells. The signal sequence for vectorization of the TF Oct4 has no effect on DNA binding to its nucleic target. As soon as one hour after injection, vectorized TFs are detectable in the nucleus. The injection process is not associated with toxicity and the bacteria can be completely removed from cell cultures. A three days targeted release of Oct4 or Sox2 embry...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research