Can Graphene be Introduced into our Bodies without Causing Rejection?

Among the many applications of graphene nanomaterials are those in the field of medicine, from cancer therapies to tissue engineering and gene transfer.

Interactions between Graphene Oxide and 15 Cell Types

The biggest barrier that products made from these materials must overcome is the immune system’s response. Now, European researchers have analyzed how our defenses behave in the presence of graphene oxide.

Graphene oxide, the oxidized form of graphene, is a carbon material with exceptional mechanical properties that could be used in medicine as a novel diagnostic and therapeutic tool. But before that step can be taken, scientists must first understand how it interacts with the immune cells that protect our bodies from invaders.

Researchers from the Universities of Sassari and Rome Tor Vergata (Italy), France’s CNRS and other European centers have developed an experimental environment to characterize the complex interactions between graphene oxide and 15 cell types in our immune system, including T lymphocytes, leukocytes, monocytes, NK cells and dendritic cells.

Data from the study, published in the journal Nature Communications, highlight the importance of “functionalizing” graphene-based nanomaterials by adding other molecules, such as amino groups, to their surface to make them more compatible with human immune cells.

“Specifically, we used single-cell mass cytometry to analyze how graphene oxide affects these cells and whether changes occur when it is ‘functionalized,’ i.e., binds to other substances,” says Lucia Gemma Delogu, co-author and researcher at the University of Sassari.

Mass cytometry makes it possible to detect subpopulations of immune cells and specific proteins of these cells, both on their surface and inside them, with enormous precision. Using this method, the researchers have been able to measure more than thirty cell markers.

“We found that graphene functionalized with amino groups increased its biocompatibility compared to normal graphene oxide,” Delague says. “In addition, we identified specific stimuli of functionalized graphene in two cell types: Monocytes and dendritic cells.”

So-called transcriptome analyses were also performed to see how the expression of immune cell genes is altered. The results confirm that the amino groups reduce the disturbances in cell metabolism caused by graphene oxide, thus increasing the biocompatibility of this material.

Biomedical Nanoplatforms Made of Graphene

“A positive effect of graphene oxide on certain immune cells can serve as a starting point for the development of biomedical platforms based on this nanoscale material, such as new immunotherapies, vaccine carriers, and nanoadjuvants,” says Delogu, who recalls that graphene nanomaterials have the “possibility” to conjugate with drugs and other molecules on their surface, “improving the function and specificity of the drug on the target of interest.”

The researcher insists that discovering the most appropriate “functionalizations” of graphene will be essential to moving forward with these and other applications in medicine: Cancer therapies, diagnostic tools for diseases, tissue engineering, transfer of genetic material, and in the combined field of biomedical imaging and neuroscience.

This study is part of the G-IMMUNOMICS project within the larger European Graphene Flagship Initiative. Using immunogenomic and protein data, graphene should be able to be used safely in medicine and elsewhere, while minimizing its impact on health and the environment. Its effects are currently being analyzed not only in human cells, but also in those of pigs, mice and the worm C. elegans.