Analyzing Antibiotcs at Work and Copying the Immune System to Attack Drug-Resistant Bacteria
The rise of bacteria that have become or have the capability to become resistant to bacteria has entered the news more and more frequently lately. It’s not difficult to see why: the image of a doctor prescribing an antibiotic as a treatment is nothing new in medicine—in fact, we might say it’s almost iconic. The idea, however, that such antibiotics might stop working—or worse, might not even work in the first place—because a bacterium has grown resistant to them is therefore one that plays right into the worst fears of science-fiction or “epidemic” fiction.
Hysteria aside, though, there are new ways that scientists and biotechnology companies are beginning to combat these resistant strains, as well as prepare for the possibility of future bacteria that may become resistant to current drugs. These take two forms that we’re talk about today: the capability to determine rapidly if and when an antibiotic has ceased to work because the bacteria are resistant, and the ability to combat bacterial infections with methods other than antibacterial drugs.
Watching Antibiotics at Work
It is already possible, and has been for decades, for scientists to watch antibiotics at work, something called “antibiotic susceptibility testing,” or AST. While the two current methods for doing this are effective and widely-used, their one drawback is that they are not useful for taking rapid tests of clinical subjects.
This is where new technology from Accelerate Diagnostics (AXDX) may come in, according to Genetic Engineering and Biotechnology Magazine. The key to their technology, which they hope will allow testing results to be obtained in as little as five hours—with identification of a bacteria in 1 hour—is the use of molecular identification and time-lapse imaging. Let’s take a look at what that means, though.
Molecular identification is actually a simple concept. Using a fluorescent probe, scientists are able to use a process called FISH (fluoresce in situ hybridization) to basically determine specific DNA features; it’s like shining a light on something, and, by following where the light binds to, figuring out what the DNA of that something is. And knowing something’s DNA is the key to knowing what kind of molecule it is—and what kind of bacteria it is.
Once the diagnostic test identifies the bacteria, the next step is to use time-lapse imagery to watch them, constantly gauging their growth rate and other factors to see if the antibiotic is still working. Time-lapse imagery is basically the opposite of slow-motion photography. Instead of playing back the photos at a rate slower than that at which they were taken (which creates slow-motion videos), time-lapse imagery plays back photos at a rate faster than they are taken, thus creating a sped-up version of events. This version is then analyzed by the Accelerate Diagnostics program to create an algorithm (basically, a set of directions to perform a group of math operations). Doctors can use the algorithm to determine not only if an antibiotic is not working in a patient (because, for instance, the bacteria are still multiplying and not slowing down), but also if it the antibiotic is working less effectively.
This latter part could be huge, according to GEN, because it will permit scientists and doctors to slow the rise of drug-resistant bacteria by alternating antibiotics when evidence begins to show that they are not working as well.
Mimicking the Immune System to Combat Bacteria
Of course, perhaps the only thing more promising that identifying when antibiotics stop working is finding something to use instead. While there are a number of companies in this field, the one we will look at today is Cellceutix Corp (CTIX).
Cellceutix’s major product is based on something called brilacidin. Brilacidin is a molecule that mimics a part of the immune system called “host defense proteins.” These are basically cells that act as the “front line of defense” for the body when it is attacked by pathogens. Unlike other antibiotics, when brilacidin attacks a bacterium, it kills it in the same way as the body would kill it.
This method of killing bacteria is significant because it means that the chance of the bacteria developing resistance is far less likely than with traditional antibiotics. While their product is just out of Phase 2 testing, brilacidin has shown itself to be active in combating both MRSA and VRE, two potent drug-resistant bacteria.
Brilacidin is far from the only method being explored, but combined with new methods of testing bacteria, it could prove an important part of tackling the rise in drug-resistant strains.
So while there’s no doubt bacteria are clever little pathogens—at least from an evolutionary perspective—the human body has some tricks up its sleeves, also. The key is using new technology to harness those tricks.
As a note, while the biotech revolution may not celebrate the holiday season, your humble analysts do, so the BTA Weekly Biotech Digest will return after the New Year to bring you more updates and analysis on new and intriguing technologies to keep an eye on.
Until then, wishing you a Merry Christmas and a Happy New Year, your analyst,
Alex