NutriChip: an electronic intestine for a healthy diet
At first glance, there seems to be little likeness between a human being and a very small pile of electronics measuring four centimetres by two. And yet, to the designers of this miniature machine, it is a sort of functional reproduction of our gastrointestinal tract. And its code name is NutriChip. The point of such a minute concentration of technology lies in its capacity to test the nutritional quality of dairy products or, more specifically, in its ability to select products which will prove to be particularly efficient in down regulating –reducing – the human body’s inflammatory response. An outcome of the Nano-Tera federal research programme
Developed within the Nano-Tera federal research programme, the NutriChip project brings together various laboratories from the Swiss Federal Institutes of Technology in Lausanne and Zurich, the University of Basel and the Agroscope Liebefeld-Posieux Research Station, along with a collaboration with the Bern University Hospital. The collaboration’s broad base is designed to take in talents from different horizons in an effort to carry through a project that borrows as much from engineering as it does from nutrition studies and medical sciences.
The Agroscope Liebefeld-Posieux Research Station is at the heart of this astonishing project. For a number of years its researchers have been seeking a greater understanding of the effects of dairy products on human health. “Various studies have already stressed the fact that the regular consumption of dairy products seems to decrease certain inflammatory reactions,” explains Guy Vergères, head of the Nutritional and Functional Biology research group at the research station. “Others claim that this is not the case. We wanted to make our contribution to this scientific issue.”
But why so much interest in dairy products? Guy Vergères explains that milk is the only substance that mammals both produce and consume. So milk must be stashed full of all sorts of goodness. What needs to be done now is to identify the nature of this goodness and any biological activities it may have. The Agroscope team is already carrying out research on human beings. A number of volunteers were asked to swallow various dairy products, and were then observed to see how their metabolism reacted to them. Screening was done by way of microarrays, which is a technology that is able to take a “snapshot” of the expression profile of thousands of genes at any given time. Microarrays are very useful for identifying genes whose expression is modified when an organism is faced with a particular stress or assimilates a given product. From in vitro to in silico
“These studies on human beings were very rewarding but they have their constraints, namely when it comes to human and financial resources,” continues Guy Vergères. “Accordingly, we sought for a way to continue our experiments by transferring them into the realm of in vitro. And that is when we heard about the Nano-Tera programme and the prospects of research across disciplines that it offered.”
A few encounters and sessions later, the project saw the light of day in March 2010 and is funded by the Swiss National Science Foundation. NutriChip is still in its infancy. It will take another two years before it is possible to estimate whether it can contribute significantly to the evaluation of nutritional benefits in dairy products. But the team’s optimism is undaunted: in fact, the feeling of uncertainty that induces greater optimism, as uncertainty always accompanies innovative projects.
“Taken separately, the technologies integrated in the NutriChip are far from revolutionary,” remarks Qasem Alramadan from the Laboratory of Microsystems at the Swiss Federal Institute of Technology in Lausanne, which is directed by NutriChip project supervisor Martin Gijs. “On the other hand, they have never been associated in this way, and even less so on such a miniature scale. The amount of liquid found in a NutriChip is measured in microlitres. Just imagine.”It’s no surprise that the engineer cites this example, since he is in charge of the microfluidics in this experiment. Microfluidics is the technology that controls the dynamics within the miniature digestive tract, which makes the chip so special. Qasem Alramadan explains why: “As it is necessary to imitate one functional part of the digestive tract, our NutriChip includes two cell cultures. One is made up of epithelial cells, which represent the first cell layer and hence the first intestinal barrier. The second is made up of macrophages, in other words one of the main classes of defence cells in the immune system.”
More often than not, an inflammatory reaction is expressed by the making of macrophages. In the presence of a pathogen, macrophages release molecules known as cytokines, which are frequently responsible for inflammatory reactions. To find out whether certain dairy products are really capable of inhibiting an inflammatory reaction in vitro, they must first be digested by enzymes that have been extracted from the digestive system itself. The resulting molecules have then to be “filtered” through a substitute for the epithelial tissue of the digestive tract. In fact, only the molecules capable of crossing this natural barrier have any effect on the macrophages or – more precisely – on the inflammatory reactions the macrophages are able to induce (and which must therefore be prompted artificially by or on the NutriChip). In so doing, these digested molecules end up in an extracellular medium in which circulate chemical messages that shuttle between epithelial cells and macrophages. Microfluidics technology thus allow two cell cultures to communicate with one another, much in the way it would happen in real life.
Though this work on microfluidics is essential to the NutriChip’s success, so is its miniaturisation, as such a tiny laboratory can detect biomarkers using as few reagents as possible. And that is not all: Sandro Carrara from the Integrated Systems Laboratory at the Swiss Federal Institute of Technology in Lausanne also intends to install an optical system on the NutriChip that will be able to detect biomarkers by way of fluorescence.
At a time when the link between nutrition and health issues is becoming increasingly significant – besides the economic opportunities it represents – firms are beginning to show an interest in the NutriChip. Guy Vergères from the Agroscope confirms that the food giant Nestlé is already aware of their research and showing interest. But he also adds that it is still too early to guarantee any applied development out of this innovative research. “We still have to carry out all sorts of experiments in order to validate the NutriChip’s efficiency. That said, we have just begun to work with Dr. Kurt Laederach of the Bern University Hospital, with whom we will be developing a protocol that will enable us to validate our conclusions with respect to human beings.” And that should be around 2013.
En français dans le texte
NutriChip : un intestin électronique
NutriChip est une sorte de reproduction fonctionnelle de notre tube digestif. Ce minuscule concentré de technologies sera capable de tester les qualités nutritives des produits laitiers. Et ce, notamment, afin de sélectionner ceux qui se révèleront particulièrement efficaces à moduler à la baisse les réponses inflammatoires du corps humain. Développé au sein du programme fédéral de recherche Nano-Tera, il réunit plusieurs laboratoires de l’EPFL, de l’ETHZ, de l’Université de Bâle, et de l’Agroscope Liebefeld-Posieux (ALP); mais également une collaboration avec l’Hôpital universitaire de l’Île, à Berne. Il intéresse des industriels comme Nestlé.