Researchers develop harmless artificial virus for gene therapy

Researchers of the Nanobiology Unit from the UAB Institute of Biotechnology and Biomedicine, led by Antonio Villaverde, managed to create artificial viruses, protein complexes with the ability of self-assembling and forming nanoparticles which are capable of surrounding DNA fragments, penetrating the cells and reaching the nucleus in a very efficient manner, where they then release the therapeutic DNA fragments. The achievement represents an alternative with no biological risk to the use of viruses in gene therapy. 

Gene therapy, which is the insertion of genes into the genome with therapeutic aims, needs elements which can transfer these genes to the nucleus of the cells. One of the possibilities when transferring these genes is the use of a virus, although this is not exempt of risks. That is why scientists strive to find an alternative. With this as their objective, emerging nanomedicines aim to imitate viral activities in the form of adjustable nanoparticles which can release nucleic acids and other drugs into the target cell.

Among the great diversity of materials tested by researchers, proteins are biocompatible, biodegradable and offer a large variety of functions which can be adjusted and used in genetic engineering. Nevertheless, it is very complicated to control the way in which protein blocks are organised, in order to form more complex structures which could be used to transport DNA in an efficient manner, as happens with viruses.

Professor Antonio Villaverde's group has discovered the combination necessary to make these proteins act as an artificial virus and self-assemble themselves to form regular protein nanoparticles capable of penetrating target cells and reaching the nucleus in a very efficient manner. In chemical terms, the key lies in a combination of cation-peptide and hexahistidine placed respectively at the amino and C-terminus ends of the modular proteins.