News | July 6, 2018

New Type Of Antibiotic Discovered

A new type of antibiotic may offer a solution to millions of COPD patients and children with middle ear infections. The drug is unlikely to have side effects and also has the great advantage that no resistance development takes place. Researchers from Radboudumc and Radboud University present their first results this week in Cell Chemical Biology.

Our body is home to millions of bacteria. That usually goes well, in fact, many of those bacteria we need to live. But sometimes the balance shifts and a hitherto innocent bacterium can suddenly make us sick. Non-typeable Haemophilus influenzae is one of them. In children, he can cause middle ear infection, a condition that affects 65 to 300 million people worldwide. It is a major cause of hearing loss. The bacterium is also found in the vast majority of patients with acute aggravation of COPD, a disease that affects three million people worldwide every year.

Invisibility cloak
To make his host ill, the bacterium needs sialic acid, a sugar that we have in our body. The bacterium does not have these sugars and steals them from us. After he has recorded them he builds them into his cell wall. As a result, he pulls a kind of invisibility cloak over him. The immune system can no longer detect it and the bacterium can take its course.

This prompted researcher Jeroen Langereis and colleagues from the Radboudumc and Radboud University University to consider whether they could inhibit the incorporation of sialic acid into the bacterial wall. They did that in separate cells and it worked. "The substance we designed for this is a new type of antibiotic," explains Langereis. The bacterium actively absorbs sialic acids via a transporter. The new antibiotic enters the bacterial cell via the same transporter. People make sialic acid themselves and do not have that transporter. The new agent is therefore not harmful to our own cells.

No resistance
The big advantage is that the bacterium can not develop resistance to the drug. Then the bacteria would have to turn off its transporter. "If he does, then that is good. By turning off the transporter, he can no longer take up sialic acid and so do not make anybody sick, "says Langereis.

'Many people with middle ear infection and COPD take antibiotics. The chance that bacteria will develop resistance to these agents is therefore great. It would be nice if you could give those large patient populations a way that the bacteria can not develop resistance to, and that works just as well.'

Another advantage is that the antibiotic works very specifically against this bacterium. It is important that a doctor knows for certain that non-typeable Haemophilus influenzae is the cause of the inflammation. Langereis: 'Now that is not necessary because antibiotics kill entire groups of bacteria.' The technique for determining this needs to be further developed. 'Normally, an antibiotic kills many types of bacteria in your body. With long-term use, the composition of bacteria in the body changes, the microbiome. As a result, people often get side effects, such as diarrhea. ' This antibiotic probably has no side effects in humans.

'A next step is to test the drug in mice. If it works just as well as in a petri dish, we will continue to humans. With a bit of luck, we can prescribe this to patients in about five to ten years' time, says Langereis.

SOURCE: Radboud University