A million times thinner than a human hair, graphene is a very thin substance. It is made of a single layer of carbon atoms, is more flexible, translucent, and electrically conductive than steel while being stronger.
A recent study found that the gut microbiota might indirectly affect the immune system using the nanomaterial graphene oxide, which is used in everything from electronics to biomolecule sensors.
the Swedish Karolinska Institutet research project on zebrafish. The journal Nature Nanotechnology reports the findings.
According to Bengt Fadeel, professor at the Institute of Environmental Medicine, Karolinska Institutet, who is also the paper’s corresponding author, “this suggests that we must take the gut microbiome into account in our knowledge of how nanomaterials affect the immune system.” “Our findings are crucial for identifying potential negative impacts of nanomaterials and reducing or avoiding such effects in novel materials,” the authors write.
A million times thinner than a human hair, graphene is a very thin substance. It is more flexible, translucent, and electrically conductive than steel and is made of a single layer of carbon atoms. It is also stronger than steel. This makes it very helpful in a variety of applications, such as in “smart” textiles integrated with wearable electronics and as a component of composite materials, to improve the conductivity and strength of current materials.
The urge to investigate how these novel materials impact the body arises from the rising use of nanomaterials based on graphene. A few studies in recent years have demonstrated that nanomaterials can also affect the gut microbiome, or the bacteria that naturally reside in the gastrointestinal tract. Nanomaterials are already known to have an impact on the immune system.
The focus of the current zebrafish investigation is the interaction between gut microbiome, nanomaterials, and immunity. The nanomaterial under investigation was graphene oxide, which is a related of graphene and contains carbon and oxygen atoms. Contrary to graphene, graphene oxide is soluble in water and is being studied in the field of medicine as a potential drug delivery system, among other applications.
In the study, scientists exposed adult zebrafish to graphene oxide through the water and examined how it impacted the microbiome’s makeup. They employed both regular fish and fish deficient in the aryl hydrocarbon receptor, also known as AhR, a receptor for a variety of endogenous and bacterial compounds, in their intestinal cells.
Guotao Peng, a postdoctoral researcher at the Institute of Environmental Medicine at Karolinska Institutet, is the study’s first author. “We were able to show that the composition of the gut microbiome changed when we exposed the fish to graphene oxide, even at a low dose, and that the AhR also affected the gut microbiome,” she said.
In order to explore the impact of specific microbiome components, in this case butyric acid (a fatty acid), which is secreted by specific types of gut bacteria, the researchers have also created zebrafish larvae that are completely devoid of a normal gut microbiome. It is well known that butyric acid can bind to AhR.
In doing so, the scientists discovered that the interaction of graphene oxide and butyric acid resulted in the development of type 2 immunity in the fish. The expression of AhR in the intestinal cells was found to be necessary for the action to occur.
“Typically, this kind of immunity is recognised as a reaction to parasite infection. According to our interpretation, the gut immune system can deal with graphene oxide in a manner similar to how it would deal with a parasite “Guotao Peng stated.
The researchers were also able to demonstrate that zebrafish larvae contain innate lymphoid cells, a part of the immune system known as innate lymphoid cells, using a sophisticated approach for mapping the immune cells.
According to Bengt Fadeel, “this demonstrates that the zebrafish is a useful model for researching the immune system, especially the primitive or innate immune system.