Microbes in medicine
There are 100 thousand billion microbes on and in our bodies. That’s ten times more than our own body cells. Microbes are involved in processes like our metabolism, and help keep us healthy by fighting off harmful intruders, for example. Slowly but surely, scientists are beginning to realise – and discover – how important microbes are in the existence and prevention of disease. New discoveries and applications hold promising opportunities for the future.
An ounce of prevention
If the microbes that we carry in our digestive system — called our (intestinal) microbiota — are out of balance, we can become ill. There are indications that we can positively influence that balance by eating healthy intestinal microbes. Previously, researchers could only isolate a select few probiotics (mostly Lactobacilli) from our intestinal microbiota or from fermented products like yoghurt. But the number of probiotics is growing. In 2013, scientists discovered a strain of intestinal bacteria that can, amongst other things, regulate the immune system and the storage of fat. Such bacteria could create a new generation of probiotics, with far more useful effects on our health.
Antibiotics and vaccines
Vaccinations and antibiotics are classics in the medical world. Every year, they save millions of lives around the world. Antibiotics are substances that kill certain bacteria or stop their growth. In nature, bacteria and fungi make antibiotics to eliminate their competitors. We use them now to protect ourselves, our pets, and other animals.
Antibiotics don’t help in the fight against viral infections. There are special anti-viral medications, but these merely stop the growth of viruses. They don’t eliminate viruses completely. When it comes to viruses, it’s mostly a question of waiting out the infection – most of them are not deadly. But we can activate our immune systems against viruses ahead of time with vaccinations. We introduce dead, weakened, or particles of a virus into our systems, usually through an injection. In reaction to this, our immune systems build up antibodies that usually protect us from a specific virus for years.
Scientists and pathogens are engaged in a real arms race. Microorganisms can adapt very quickly, for example by changing their DNA within a few generations or exchanging it with other pathogens. That’s why there are constantly new microorganisms that replicate rapidly. Also, resistant pathogens can evolve quickly, whereby existing medications become no longer effective. The emergence of resistant microbes causes more and more problems. That’s why researchers are eagerly looking for new antibiotics, for example in remote areas like deserts and jungles.
The progression of technology helps us understand processes better and better. For example, we can now isolate and deploy individual proteins, instead of whole organisms. Scientists also have their eyes on other interesting antibiotic successors: bacteriophages. Those are viruses that only infect and kill certain bacteria. That’s how bacteriophages — and components of bacteriophages — are forming a potentially ground-breaking alternative to antibiotics that now only prevent further growth. But it only works if you know precisely which specific bacteriophage fights which pathogen. There is currently a full-on investigation underway to find out.
The problem with medicine is often that, once they are discovered, they aren’t immediately available in large quantities. Therein lies a great opportunity for biotechnology. Microorganisms have already proven that they can function as powerful medicine factories. That’s how insulin for diabetics, once acquired with great difficulty from the pancreas of pigs, can now be produced in large quantities by fungi in fermenters. Fermenters are large kettles in which microorganisms can be cultivated under controlled conditions.
Modern genetic research can determine which gene or gene packet codes the substances that can fight a particular disease. If that gene or packet can be isolated, and a microorganism can be found to make the substance, a lot of progress can be made. If there’s an outbreak of a new disease, medicine can win the race against the clock.
Hidden treasure under the sea
Marine biotechnology is also very promising for medical applications. We’re sending probes to Mars, but the rich underwater world on our own planet has hardly been explored at all. That’s beginning to change now. Undersea exploration is expected to deliver new insights and applications for combating disease. Marine (micro)organisms have a wide variety of chemical means with which to communicate and to protect themselves from their enemies. In the past 40 years, more than 30,000 new chemical substances, made by sea organisms, have been discovered in shallow tropical waters alone. If organisms use these substances to fight off enemies, then there’s a good possibility that they can also fight disease. As knowledge about the role of these compounds increases, so too does the opportunity for the development of new medications.