Genetically-modified fly larvae can be used to boost the healing process of non-healing wounds sustained by diabetics, says a new study published in BMC Biotechnology.
The use of lab-grown green bottle fly larvae for maggot debridement therapy (MDT) is approved by the FDA (Food and Drug Administration). The maggots are placed on non-healing wounds of diabetics, for instance, to promote the process of healing. However, while the maggots do clean the wound by secreting anti-microbial factors and removing dead tissues, it is not confirmed whether it reduces healing time. This is what a team of researchers of North Carolina State University and Massey University led by Professor of Entomology, Max Scott, wanted to create: maggots that actually display boosted wound-healing capacity.
Genetically-modified green bottle fly larvae of the species Lucilia sericata were used to make a molecule that would assist the process of wound healing by triggering cell growth and survival. The larvae would then synthesise and secrete a compound known as a human-platelet-derived growth factor-BB (PDGF-BB). Two distinct methods were used to generate the PDGF-BB from the fly larvae.
One of the techniques entailed the synthesis of PDGF-BB through heating. The larvae went through a state of shock with high heat (37 degrees Celcius). This led to the production of the growth factor in some regions of the larvae. However, the PDGF-BB was found in neither the secretions nor the excretions of the maggot. This method, therefore, proved to be inefficient — it could not be used for clinical applications, said Scott.
Fortunately, the second technique was more fruitful. The flies were genetically modified to make PDGF-BB only when they were fed a diet without antibiotic tetracycline. This resulted in high yields of the PDGF-BB in the larvae, and the compound was detected in their secretions and excretions.
Scott hence deems the latter method as suitable for clinical use. He describes their study as a “proof-of-principle” one for the potential use of genetically-engineered L. sericata strains to generate growth factors as well as anti-microbial peptides to provide a cost-effective way to treat wounds of people suffering from the negative consequences of diseases like diabetes. Patients might thus be saved from amputations and the likes.