In the world of science, the mouse has been for decades the undisputed king of the laboratory. However, it is an expensive, slow and, above all, ethically complex reign. That is why we have been looking for alternatives for years, and the answer may not be in a silicon chipbut an insect that you have probably seen eating the wax of a beehive.
The advance. This is what researchers at the University of Exeter have arrived at, who have achieved a milestone that promises to change the rules of the game in the fight against superbacteria: They have genetically “hacked” dinner moth larvae to function as real-time biological indicators.
The most impressive thing is that they even have a very visual indicator: they shine when you get sick and go off when the medicine is working correctly.
The biological traffic light. The study, published this week in Naturedetails how the research team has achieved what seemed impossible: applying tools of genetic editing advanced these moths with unprecedented precision. And I know this is very important, since using insects to model human diseases had limitations, but this team has combined two key techniques.
The techniques. The first of them is the system PiggyBac to be able to insert genes that produce fluorescent proteins into these moths, so they have basically gone from having larvae to biological “neon lights.” In this way, if bacteria or fungi are injected, fluorescence makes it possible to monitor the infection in vivo under the microscope.
In addition, the famous technique was also included CRISPR-Cas9 to deactivate specific genes in the insect’s body. This is a tremendously positive thing, as it allows scientists to manipulate the larva’s immune system to see how it reacts to different pathogens, mimicking complex human conditions.
The key data. The bottom line is that the modified larvae allow us to see if an antibiotic is working in real time. The indicator we have is fluorescence, which if it decreases indicates that the bacteria is dying from the antibiotic and the larva is surviving. All this in a visual, fast and cheap way.
Why the moth. It may sound strange to compare a moth with a mammal such as the mouse, which may be more like us, but the Galleria mellonella He has an ace up his sleeve: your body temperature.
Unlike the fruit fly, these larvae can breed and survive comfortably at 37°C, the average human body temperature, which is crucial because many human pathogens only activate their virulence genes at that temperature. Furthermore, their innate immune system is surprisingly similar to that of mammals in terms of structure and function of phagocytes, the cells that literally ‘eat’ pathogens that enter the body.
Furthermore, with this animal model the use of 10,000 mice per year in the United Kingdom alone can be avoided.
Against the clock of the resistance. The context of this advance is not trivial, since we are facing a race against the resistance of bacteria to our antibiotics. We need at this moment test thousands of new compounds fastand doing it in mice is a brutal bottleneck both because of the time it takes and the ethical questions that arise.
On the other hand, these transgenic larvae allow for massive screening. Instead of waiting weeks to see results in mice, scientists here can test hundreds of compounds in larvae and get immediate visual readings on toxicity and efficacy.
Images | Wikipedia Kalyan Sak
GIPHY App Key not set. Please check settings