Overcoming Proteasomes: One Step Closer to a Cure for Cystic Fibrosis
Take a deep breath and consider how easy it was to do so. Now picture struggling and
gasping for air everyday; normal, easy tasks to the average person prove to be quite challenging
to a patient of cystic fibrosis. Scientists have always been daunted by this fatal genetic disease
that affects the body by excreting a “thick mucus” in the lungs, making breathing difficult and
blocking the “ducts” leading from the pancreas, causing “poor digestion of food” (1). Until
recently, there was nothing that scientists could do to provide a long-term cure, but even though
scientists cannot cure patients one hundred percent, they can increase their life expectancy.
Despite having discovered the cystic fibrosis gene’s location in 1989, numerous underlying
obstacles prevent complete success (2). The primary obstacle that prevents scientists from
making gene therapy an effective cure is the placement of the healthy genes into long-term cells,
the cells that remain long enough to be replicated. The replacement of the healthy gene into
long-term cells is necessary because these cells make the new cells, thereby distributing the
healthy DNA throughout the body. The properly functioning gene is attached to a vector or
“carrying molecule” that will transport “the therapeutic gene to the patient’s target cells” (2).
Currently, the most common vector is a virus because it can easily capture the gene and deliver it
into the cell; the virus infiltrates the corrupt cells and places the healthy gene into the nucleus
which then transforms the corrupt cell into one which operates properly (2). The only difficulty
is that the body’s natural immune system provides many barriers for viruses trying to enter the
body. Scientists have managed to stop parts, but not all, of the immune system from breaking
down the viruses that carry the healthy gene, giving scientists an opportunity to develop a
method for inserting the healthy genes into long-term cells.
Since scientists started using a virus as the carrying molecule, the virus has shown
considerable effectiveness on the cells that is inserted into; however, repeated doses are
necessary. Some commonly used viruses are “Retroviruses, Adenoviruses, Adeno-associated
viruses, and Herpes simplex viruses” (2). The primary virus used in gene therapy is the “adenoassociated
virus” (AAV), because they are able to “insert their genetic material at a specific site
on [the] chromosome” (2). And even though “trials experimenting with gene therapy” as a
possible cure for cystic fibrosis have been unable to show that “gene transfer efficiency” is
significant enough for “clinical benefit”, which is due to the natural bodily defenses in the
“airway,” this does not mean this method cannot be perfected (2).
The obstacles preventing scientists from developing a cure include finding a way to
overcome the short life-span of cells with newly...