In all bodily fluids it's possible to find exosomes and nanometer-sized vesicles that mediate a lot of intercellular communication both in health and diseases. Some of these exosomes are unique to tumors, when it comes to their compositions, and scientists have long sought to use them as biomarkers to spot and treat cancer. Finding them in blood, saliva, or urine is usually a laborious process, so researchers thought that tears might be a better candidate for collection using a contact lens.
Exosomes in particles are considered to play a crucial role in the metastasis of cancers when tumors spread from one location to another in the body. Current methods usually extract the exosomes from bodily fluids using centrifuges and density gradients in a process that can take ten hours to complete. The specialized equipment to detect isolated exosomes makes the process long and expensive.
In tears, exosomes are much easier to detect. How do you collect them? Instead of making someone watch Simba finding the body of Mufasa on loop for 10 hours to collect enough, the researchers used a contact lens that is equipped with nanoparticles that can tag specific antibodies and make them react to molecules on the surface of the exosomes.
As reported in Advanced Functional Material, the team tested it not on humans but in vitro. The gold nanoparticles reacted to exosomes in a liquid with the same pH as human tears as well as real human tears. The researchers showed that the tech could differentiate between the surface proteins of exosomes believed to be cancer biomarkers.
The contact lens was developed by the Terasaki Institute for Biomedical Innovation (TIBI). The microchambers that store the gold nanoparticles were engraved using a laser and then modified with chemicals. This allowed the lens to have a good level of transparency and proper mechanical properties, as well as being ok for human use.
“Exosomes are a rich source of markers and biomolecules which can be targeted for several biomedical applications,” Dr Ali Khademhosseini, TIBI’s Director and CEO, said in a statement. “The methodology that our team has developed greatly facilitates our ability to tap into this source.”
The team believes that this method could be a very easy, quick, and certainly non-invasive approach to screening for potential cancer as well as conducting supportive diagnosis. It has also the potential to be a cost-effective screening solution.