The lens was designed with microchambers bound to antibodies that can capture exosomes found in tears. This antibody- conjugated signaling microchamber contact lens (ACSM-CL) can be stained for detection with nanoparticle-tagged specific antibodies for selective visualization. This offers a potential platform for cancer pre-screening and a supportive diagnostic tool that is easy, rapid, sensitive, cost-effective, and non-invasive.
Exosomes are formed within most cells and secreted into many bodily fluids, such as plasma, saliva, urine, and tears. Once thought to be the dumping grounds for unwanted materials from their cells of origin, it is now known that exosomes can transport different biomolecules between cells.
There has been much interest in using exosomes for cancer diagnosis and prognosis/treatment prediction. However, this has been hampered by the difficulty in isolating exosomes in sufficient quantity and purity for this purpose. Current methods involve tedious and time-consuming ultracentrifuge and density gradients, lasting at least ten hours to complete. Further difficulties are posed in detection of the isolated exosomes; commonly used methods require expensive and space-consuming equipment.
In an initial validation experiment, the ACSM-CL was tested against exosomes secreted into supernatants from ten different tissue and cancer cell lines. The ability to capture and detect exosomes was validated by the spectroscopic shifts observed in all the test samples, in comparison with the negative controls. Similar results were obtained when the ACSM-CL was tested against ten different tear samples collected from volunteers.
In final experiments, exosomes in supernatants collected from three different cell lines with different surface marker expressions were tested against the ACSM-CL, along with different combinations of marker-specific detection antibodies. The resultant patterns of detection and non-detection of exosomes from the three different cell lines were as expected, thus validating the ACSM-CL’s ability to accurately capture and detect exosomes with different surface markers. (NS/Newswise)
