Abstract
Recent works have proposed the use of proteins instead of DNA/RNA as molecular tools for the modulation of gene expression patterns in stem cells. To obtain insulin-producing cells, certain proteins including Pdx-1, Isl-1, Pax-6, and Neuro-D, can be expressed or modified with transduction domains in order to penetrate and reprogram target cells. However, numerous aspects must be taken in account, including the fact that not all proteins may be used in transduction protocols. Thus, new methods must be developed. In this report we studied whether liposomes can work as carriers to introduce reprogramming protein extracts inside adipose tissue mesenchymal stem cells. To this end, the cells were incubated for 8 h in the presence of liposomes containing MIN-6 protein extracts. Charged liposomes fused with 70% of the cells, transferring their contents and transiently (up to 48 h) changing the gene expression pattern for specific endocrine pancreatic genes coding for Insulin-I, Insulin-II, Glucagon, Isl-1, MafA, and Nkx-6.1. No expression of Foxa-2, Pax-6, and Pdx-1 was observed. Although preliminary, the obtained results suggest that the use of liposomes for reprogramming techniques opens new possibilities for cell therapy.
