Antimicrobial resistance (AMR) happens when micro-organisms such as bacteria, fungi, viruses, and parasites undergo a metamorphosis when they are exposed to antimicrobial drugs such as antibiotics, antifungals, antivirals, antimalarials, and anthelmintics.
When micro-organisms have developed antimicrobial resistance they are referred to as superbugs.
Consequently, the medicines that once were effective in the treatment of infections have become ineffective. This causes the infections to persist in the body, potentially increasing the risk of extended infections and also increasing the risk of spread to others.
Antibiotic resistance evolution
Antibiotic-resistant infections kill a whopping estimate of 700,000 people annually around the world. Antimicrobials and antibiotics are increasingly misused and overused by the global population.
On occasions, many health practitioners prescribe antibiotics for extended periods of time or for conditions where other alternative treatment would be enough. All this has contributed enormously to help organisms become increasingly resistant to antibiotics in a very short period of time.
Scientists say that there could be profund health and macroeconomic global consequences, especially in emerging economies, if antimicrobial resistance (AMR) is not properly tackled. To top it all, on occasions, research into new drugs advances at the pace of a snail.
How to kill a superbug
In order to help with this urgent global situation, Massachusets Institute of Technology (MIT) chemical engineers have found a way to encapsulate probiotics in a way that they can be delivered along with antibiotics. As a result, this innovative procedure kills multiple strains of bacteria.
A common problem with administering probiotics as an alternative treatment method lays on the fact that probiotics are often incompatible with antibiotics which results in killing their overall therapeutic utility.
In their study, Biofilm-Inspired Encapsulation of Probiotics for the Tratment of Complex Infections, published in the journal Advanced Materials, the researchers explain how they encapsulated the probiotic bacteria in a protective shell of alginate which is a biocompatible material that prevents the probiotics from being killed by the antibiotic.
According to the researchers, by delivering a combination of antibiotic drugs and probiotics they were able to eradicate two strains of drug-resistant bacteria that is often found in infected wounds.
“There are so many bacteria now that are resistant to antibiotics, which is a serious problem for human health. We think one way to treat them is by encapsulating a live probiotic and letting it do its job,” says Ana Jaklenec, a research scientist at MIT’s Koch Institute for Integrative Cancer Research and one of the senior authors of the study.
Other senior authors include Robert Langer, who is David H. Koch Institute Professor and a member of the Koch Institute, and Zhihao Li, a former MIT visiting scientist, who is the study’s lead author.
According to Zhihao Li, scientists have tested the idea of applying probiotics to chronic wounds before with some success in studies of patients with burns. However, the probiotic strains can't combat all the bacteria that would be found in an infected wound.
Li says that combining these strains with more traditional antibiotics could potentially kill more of the pathogenic bacteria, but the antibiotic would most likely also kill off the probiotic bacteria.
The team of researchers finds their solution viable and explain in the paper that the choice of alginate is in part because it is already used in dressings for chronic wounds since it helps to absorb secretions and also keeps the wound dry.
In addition, the scientists found that alginate is a component of the biofilms that clusters of bacteria form to protect themselves from antibiotics.
“We looked into the molecular components of biofilms and we found that for Pseudomonasinfection, alginate is very important for its resistance against antibiotics,” Li says. “However, so far no one has used this ability to protect good bacteria from antibiotics.”
For this study, the scientists encapsulate a type of probiotic known as Bio-K+, a commercially available probiotic that consists of three strains of Lactobacillus bacteria. These three strains kill methicillin-resistant Staphylococcus aureus (MRSA).
“The good thing about alginate is it’s FDA-approved, and the probiotic we use is approved as well,” Li says. “I think probiotics can be something that may revolutionize wound treatment in the future. With our work, we have expanded the application possibilities of probiotics.”
According to the researchers, the probiotic/antibiotic combination could help heal infected chronic wounds. After further testing, the new approach in animals and humans potential applications could include the development of new types of bandages or other wound dressing embedded with antibiotics and alginate-encapsulated probiotics.
Zhihao Li’s work on this project was funded by the Swiss Janggen-Poehn Foundation, and by Beatrice Beck-Schimmer and Hans-Ruedi Gonzenbach.