DNA-binding Self-assembling Peptide Amphiphile System for the Transfection of Cellular Aggregates (27116)
A self-assembling peptide system utilizing a bioactive sequence which significantly enhances transfection efficiency.ADVANTAGES: A self-assembling peptide system able to transfect aggregates of cells more completely and with higher efficiency than present day commercial reagents. The system appears useful for a variety of cells including stem cells or organiods such as the Islets of Langerhans.
SUMMARY: Transfection is the process by which foreign DNA is introduced to a cell, transported from the cell membrane to the nucleus, where it can direct cellular processes expressing the proteins for which it encodes. A variety of transfection systems exist including mechanical, electrical, viral, and chemical methods. Chemical methods (lipofection) are commonly viewed as the least harmful to the transferred cells. Lipofectamine®, a commercial product, is widely used for this purpose. This cationic lipid reagent complexes with DNA, decreasing the effective charge of the complex thereby facilitating passage of the complex through the cell membrane. The reagent appears to be a passive carrier and does not direct the fate of the complex.
This invention improves on the above reagent by incorporating a peptide which is bioactive and directs the complex to the nucleus. It is designed to form an alpha helix which binds to the major groove of the double helix of DNA. In addition, it is a self-assembling peptide amphiphile (PA) which forms high aspect ratio nanostructures. When complexed with DNA, these nanostructures are, on average, smaller than the nanostructures produced by Lipofectamine® as determined by dynamic light scattering. This DNA-PA complex by virtue of the peptide region also contains a bioactive nuclear localization signal which directs the cell to move this complex through the cytoplasm and into the nucleus where the genes encoded in the DNA are subsequently expressed.
Studies with P19 (ATCC No.CRL-1825™) cells demonstrate improvements of this system over the commercial product are most visible in cellular aggregates in which a large increase in transfection is seen both in the number of mRNA transcripts contained within the cells (Figure 1) and in the actual protein production (Figure 2). Up to 10-fold increase in the mRNA transcript and threefold increase in the protein expression is observed compared to Lipofectamine®.
Inventor(s): Samuel I. Stupp and Chung-Yan Koh
Type of Offer: Licensing
« More Medical Patents