Medicine of the future: Mucus and mucins

Many people automatically connect mucus with something repulsive, yet it actually serves a variety of important health roles. It maintains track of the bacteria in our intestines and feeds them. It protects us from infectious diseases by covering all internal body surfaces and acting as a barrier to the outer world.

Because mucus functions as a filter, keeping bacteria in or out, and bacteria feed on the carbohydrates in the mucus between meals, this is the case. So, if we can employ the correct carbohydrates to make the mucus that is already present in the body, it could be used in entirely new medical therapies.

Researchers from the DNRF Centre of Excellence, Copenhagen Center for Glycomics, have now figured out how to make healthy mucus artificially.

'With the help of their sugars contents, we've created a method for synthesizing the important information found in human mucus, also known as mucins. Professor Henrik Clausen, main author of the study and Director of the Copenhagen Center for Glycomics, adds, "Now we show that it is possible to artificially generate it in the same manner that we produce other therapeutic biologics today, such as antibodies and other biological medication."

Sugars make up the majority of mucus, or mucins. The researchers reveal that the bacteria recognize certain patterns of sugars on the mucins in their study.

'It's the body's way of prioritizing healthy bacteria over disease-causing microorganisms.' And it's the sugars in the mucus that we can now design as needed,' explains Rebecca Nason, Ph.D. student and first author of the work.

The mucus in the gastrointestinal tract is of great interest to the researchers. The mucus, like a gigantic fishing net, maintains track of all the microorganisms in our microbiome. So, if one could mimic bacteria's capacity to connect to intestinal mucus, one could create oral drugs that adhere to the mucus, increasing their effectiveness.

'We've discovered a tiny chemical from bacteria called X409 that binds to the intestine, and it's one of the many options we're looking into right now,' says Rebecca Nason.

When medicine must be swallowed and absorbed into our intestinal system, it might be challenging to get it to work. As a result, designing your drug as a pill for the patient to ingest does not guarantee that it will be totally effective.

There are many hurdles on the way down through the digestive system, and the medication takes time to dissolve and disperse in the body in the gastrointestinal tract,' adds Rebecca Nason.

Every day, we ingest more than a litre of mucus in the form of saliva and even more from the stomach, which, along with the constantly changing fishing net of mucus in the gut, feeds our intestinal microbiota. The microbiome of the intestine is extremely important for human health and is linked to a variety of disorders.

'The gut flora is linked to an enormous variety of diseases, yet we still know very little about how to manage the flora in the therapy of diseases.' Synthetic mucins could open up new therapy possibilities in this case,' says Associate Professor Yoshiki Narimatsu, one of the study's principal authors.

According to Yoshiki Narimatsu, "ultimately, one may picture using mucins as a pre-biotic material, that is, as molecules that help the good bacteria in the body."

It will also be feasible to treat illnesses in the body with artificial mucus. Saliva contains mucus, which flushes out bacteria and cleans the oral cavity, and mucus also washes down over our eyes, keeping them clean.

'Instead of using antibiotics, we imagine you might make eye drops with mucin, which is used to eliminate bacteria in the treatment of eye infections.' According to Yoshiki Narimatsu, "this suggests that mucin can disintegrate the so-called biofilm of bacteria, which is often harmful."

Biofilm is a bacterial film that forms on the surface of a material and is what you can feel on your teeth if you haven't brushed them in a long time.

Mucins are recognized by more than just bacteria.

'We also show that mucins are critical for the way the common flu virus penetrates our mucous membranes, competing with mucins that block infection and wash the virus out,' Yoshiki Narimatsu explains.

The influenza virus, unlike the covid-19 virus, binds to a sugar found on all mucins, and a sugar has previously been created to treat the flu.