Genetic defects cause cancer and many other life-threatening diseases because such damaged genes prevent the normal functions of the body.  These mutated genes prevent the normal functions and other activities of the said genes.  As such, gene therapies are employed in order to correct such defective functions.  With the use of viruses in gene therapies, healthy genes can replace their defective counterparts in cells.  Viruses became the media to embed such corrective genes.

Recently, new approaches to the insertion of such correcting genes have been developed.  The new techniques make use of synthetic viruses, which pose lesser threats of pathogenic side effects.  The synthetic viruses are custom made in order to permit their exclusive binding with affected cells and not to attach themselves with healthy ones.

For the first time, researchers at Ludwig-Maximilians-Universität (LMU) Munich were able to analyze the underlying causes of changes or growth of three different targeted custom made viruses in living cells.  This team was led by Professor Christoph Bräuchle of the department of chemistry and biochemistry and Professor Ernst Wagner of department of pharmacy.

For studies like these, a microscope for phase contrast would be a good tool in observing the dynamics of living cells.  A microscope for phase contrast permits the examination of living cells in their natural state.  As such, ongoing biological processes can be studied under this microscope for phase contrast.

The scientists have reported in the journal “Molecular Therapy” that one of these synthetic vectors recognized the Epidermal Growth Factor Receptor or EFRG.  The said EFRG is highly present on the surfaces of various tumor cells among humans.  With the aid of a microscope for phase contrast, the interaction between substances in cells has been studied.  Images demonstrated that particular molecule has accelerated and facilitated the absorption of synthetic viruses.  These processes are considered to be the important steps in an efficient gene therapy.

The said synthetic vectors need to invade cells for replication.  Herein, they stop their hosts’ metabolisms thereby preventing the production of a new virus generation.  As such, the said vectors enable the transportation of corrective genes in the said therapy.  It is important to note, however, that the safety of such new approach is dependent on the ability of the artificial viruses to efficiently act like their natural counterparts.

According to Wagner, the research team had used polyplexes, which are the complexes of: a molecule, which store genetic information; DNA; and polyethylenimine chemical or PEI.  It was reported that only one of these variations carried the epidermal growth factor or EFG.  The said molecule is essential in the regulation of cellular growth and other important processes.  It has been observed to enter the cells through tying itself to receptor EGFR on the surfaces of cells.  Thus, acting as a lock and key.  Since a broad range of human tumor cells display elevated levels of EGFR on the outside, the said attached molecule makes as an attractive target for gene therapy.  Furthermore, with the aid of a microscope for phase contrast, it has been observed that polyplexes with EGF are internalized much faster.  Thus, making the said synthetic viruses useful in the development of gene therapy techniques.Read on this subject