Researchers from DTU Health Tech have developed a system for sampling bacteria from the small intestine to provide more knowledge about our digestive system, and how it affects our health.
The small intestine is the region between our stomach and large intestine or colon. It is important to learn more about what kind of bacteria communities that live in the small intestine where a lot of the digestion of food and glucose absorption take place. We also know that our immune system is affected by the conditions in our gut, and that much of the immunity that we develop is influenced by the bacteria living in the small intestine. Diseases such as inflammatory bowel syndrome, colitis, ulcers and obesity are associated with dysbiosis, a microbial imbalance in the gastrointestinal (GI) tract. The GI tract is the tract from the mouth to the anus including all organs of the digestive system.
Medical doctors call for more knowledge of our gut microbiota. And the small intestine is particularly difficult to sample. Researchers from the IDUN Center of Excellence at DTU Health Tech and colleagues from University of Copenhagen and the Danish Technological Institute have shown the first proof-of-concept for a new technology, which can take a sample from the small intestine.
Postdoc Sarvesh Kumar Srivastava explains, “To isolate the microbiota or bacteria in our gut is the first step in getting to know them, how they interact with one another and with our body. The most commonly used sampling technique today is stool sampling. The problem is that these samples do not accurately represent the bacterial composition in the small intestine as they have been subject to quite different environments on their way out of the body .”
Like a sponge
With their new system, the researchers are able to collect bacterial samples in the small intestine to identify its exact composition with 16s amplicon sequencing. The system is orally ingestible and consists of a small capsule with a pH sensitive lid, which opens when it is subjected to the pH value in the small intestine. When the lid is open, the content of the capsule reacts with the fluids in the small intestine and an in situ polymerization process initiates.
“Much like a sponge when wet, it swells and absorbs everything in its vicinity, and whatever is in the fluid gets caught in the gel matrix that has emerged from the self-polymerisation”, Sarvesh Kumar Srivastava explains.
In the study, which has recently been published in the scientific journal ACS Nano, the researchers show that their self-polymerizing microsystem can collect microbiota that can be isolated and analysed after being enmeshed in the gel.
The next step
Further down the road, one could imagine many applications for the new system. For example, isolation of antibiotic resistant bacteria in the gut. Before administering a specific type of antibiotic, it would be beneficial to know whether the patient has resistant bacteria in their gut to exactly that kind of antibiotic. “In addition to collecting the bacteria from a specific place, these microsystems could potentially be used to deliver biologics, like insulin, as demonstrated with our cell study in the presence of mucus” adds Lina Gruzinskyte, PhD.
For now, this so-called TRAP technology is the first step towards a new way of non-invasive sampling of our gut content. “There is a lot of work ahead and we are excited to mature this technology further so that it can help patients in the clinic soon”, Sarvesh Kumar Srivastava adds.
Link to the article: https://pubs.acs.org/doi/10.1021/acsnano.0c05426
Caption: The top image is a scanning electron microscopy photo of hydrogel formation inside a hollow microdevice.