Caehnorhabditis Elegans: A Low-Cost In Vivo Animal Model for Efficacy Studies of Novel Antibiotics

Since the 1940s, antibiotics have greatly reduced the adverse effects of infectious diseases caused by microbes. However, due to excessive, and often incorrect, use of known antibiotics, many organisms have adapted antibiotic resistance. Currently, over 70% of known infectious bacteria are resistant to at least one antibiotic. In the U.S. , 90,000 deaths occur each year due to infection by bacteria resistant to antibiotics. This number has increased by nearly 75,000 in the last 20 years. It is necessary, therefore, to continue developing new antibiotics in an effort to keep up with increasing antibiotic resistance. Traditional in vitro and whole cell drug screens are inefficient. Unlike in vitro studies, in vivo studies can rule out toxic compounds early in analysis. They can also test compounds in the presence of important host/pathogen relationships. The action of an antimicrobial can therefore be viewed within the context of the whole organism, and not just at the drug-receptor site, as in vitro . Current in vivo testing is done in small mammals, such as mice. Mice, however, are resource intensive to maintain. Often, the antibiotic compounds being tested are toxic to the mice, killing them and creating a need for new miceB• Our lab group has proposed the use of the nematode Caenorhabditis e/egans for in vivo tests as an intermediate step prior to testing in mammals