“We’re sorry to inform you, but you have hepatitis C.”
In just ten short words, patient Paula Francis received a blow that changed her life forever. This was the last diagnosis Francis was expecting after going to the doctor with what she though was the flu. Little did the stay-at-home mom know that she had actually been living with this disease for several years. Like many other patients with the hepatitis C virus, or HCV, Francis had acquired hepatitis C through the use of unsterilized needles. More disconcerting than the diagnosis itself, however, was the apparent lack of available treatments. Like many patients, Paula felt lost.
A Lack of Options
Although there have been many recent advances in antiviral drugs to help treat Hepatitis C, for many patients, these drugs are difficult to obtain as they are administered by very few facilities and are exceedingly expensive. Moreover, many of these drugs have negative side effects. In response to this lack of options for patients like Paula, scientists like Dr. Alexander William Tarr of the University of Nottingham are on the lookout for a more accessible and cost-effective way to treat hepatitis C.
Tarr and his colleagues have decided to investigate alpaca nanobodies because of their remarkable effect on HCV. These antibody fragments can easily attach to the HCV antigen and inhibit them, something that other commonly-used antibodies cannot do. Alpaca nanobodies are also exceptionally malleable and are easy to mass produce. After all, alpaca farms are much more prevalent and accessible than high-tech labs, so a drug potentially made from alpaca nanobodies is much more cost effective. With this in mind, the researchers decided to test four different types of alpaca nanobodies in order to determine which one is the most effective.
Alpaca nanobody D03 was the most successful in the experiment; not only was it able to inhibit two different strains of HCV, but it was also able to function in six unique genotypes of HCV, while the current antiviral drugs can only inhibit one HCV genotype. After a closer look at the crystal structure of nanobody D03, scientists found that it uniquely folds in such a way as to prevent the cell-to-cell transmission of HCV. This means that a drug made from the D03 nanobody could be the first drug to stop the spread of HCV throughout the body.
In a follow-up experiment, researchers found that HCV is not the only virus alpaca nanobodies can inhibit; they can also inhibit cells in many other types of retroviruses. Now, hepatitis C patients such as Paula have a glimmer of hope for a more effective and accessible treatment. Tarr’s findings could lead to an HCV drug that would be life-changing for patients just like Paula. Clearly, alpacas have a huge future ahead of them, not only on farms, but also in labs.