Bacteria-Killing Immune Proteins Pave Way for New Infection Treatments

PhD scholar Shouya Feng (L) and Professor Si Ming Man. Photo: Dr Chinh Ngo/ANU. Supplied by ANU

Australian researchers have discovered a specific group of bacteria-killing proteins innate to our immune systems, which may lead to the development of more effective drugs capable of combatting infectious diseases such as pneumonia, meningitis, and sepsis.

The Australian National University (ANU) team, which saw its findings published in Nature Communications, demonstrated the ability of these immune proteins to directly bind and destroy certain types of bacteria.

As well as paving the way for new treatments for bacterial infection, the killer proteins also show the potential to be used together with existing antibiotics to reduce antibiotic resistance, thus providing a broader range of treatment options.

Lead author Shouya Feng from ANU’s John Curtin School of Medical Research said in a statement that these proteins—known as guanylate-building proteins (GBP)—work by breaking open bacteria in a manner similar to an ax splitting a piece of wood in two.

“Our immune system is equipped with weapons that can destroy germs. When foreign bodies, such as bacteria, enter our body, the immune system triggers a defensive response,” she said. “We believe we can extract and harness the power of these immune system proteins, known as GBP1, and use them to treat a range of infectious diseases without negatively affecting our body’s cells.”

Getting Around Antibiotic Resistance

According to World Health Organisation research, drug-resistant diseases currently cause about 700,000 deaths globally each year, with the figure expected to increase to about 10 million by 2050.

Si Ming Man, coauthor of the research, said disease-causing bacteria are continually outsmarting drug treatments through adaptation, and scientists are always on the lookout for fresh ways to develop more effective treatments.

“The extensive use of antibiotics to treat a number of different infectious diseases over many years has made them less effective over time because microbes are continually developing resistance to new and existing treatments, meaning they’re staying one step ahead of scientists,” he said.

“We are now finding more and more GBPs that can kill different types of drug-resistant bacteria. This includes bacteria that can cause meningitis, pneumonia, and sepsis.”

Man said the research could lead to alternatives to increasingly overused and ineffective antibiotics by making new methods available to combat these multidrug-resistant infections.

Large Scale Production in Lab and Potential to Treat Malaria

Feng told The Epoch Times on Aug. 8 that a constant biological source of GBPs isn’t required, as the active portion can be synthesised in the lab.

“We found that a very specific region of this protein is responsible for killing the pathogen, so what we did is synthesise this small region, and then it’s easier to produce on a large scale and easy to store as well, so we don’t need to go back to the biological source and repurify it,” she said.

Feng also noted that GBPs may have the potential to treat malaria because they have similar features to bacteria killed by the proteins in the lab.

Man said the research could be the cornerstone of a new framework to inform how continually-evolving diseases might be best fought for decades to come.