Noninvasive Cancer Diagnosis with a Contact Lens-based System that Collects and Analyses Tear Exosomes
By LabMedica International staff writers Posted on 12 Aug 2022 |
A novel contact lens-based system for noninvasive cancer screening and diagnosis concentrates and analyzes exosomes shed by cancer cells into tears.
Exosomes are formed within most cells and secreted into many bodily fluids, such as plasma, saliva, urine, and tears. They are lipid-bilayer-enclosed structures, with sizes ranging from 30 to 5,000 nanometers. In the past decade, exosomes have emerged as important mediators of cell communication because they serve as vehicles for the intercellular transmission of biological signals (proteins or nucleic acids) capable of altering cell function and physiology. In addition, exosomes related to cancers have been reported to exist in tears.
The use of exosomes for clinical purposes has been hindered by difficulty in isolating them in sufficient quantity and purity. Current methods involve tedious and time-consuming ultracentrifuge and density gradient techniques, lasting at least ten hours to complete.
To overcome this shortcoming, investigators at Terasaki Institute for Biomedical Innovation (Los Angeles, CA, USA) developed a poly(2-hydroxyethyl methacrylate) contact lens embedded with antibody-conjugated signaling microchambers (ACSM-PCL) capable of detecting tear exosomes. Microchamber surfaces were chemically modified to activate them for antibody binding, and procedures were optimized for binding a capture antibody to the ACSM-CL microchambers and a different (positive control) detection antibody onto gold nanoparticles that could be visualized spectroscopically.
Results revealed that the ACSM-PCL could detect exosomes in the pH range of 6.5–7.4 (similar to the pH of human tears). In particular, the ACSM-PCL could detect exosomes in various solutions, including regular buffer, cell culture media from various cell lines, and human tears. Furthermore, the ACSM-PCL could differentiate expression of exosome surface proteins thought to be cancer biomarkers.
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.
“Exosomes are a rich source of markers and biomolecules which can be targeted for several biomedical applications,” said senior author Dr. Ali Khademhosseini, director and CEO of Terasaki Institute for Biomedical Innovation. “The methodology that our team has developed greatly facilitates our ability to tap into this source.”
The contact lens system for capture of exosomes from tears was described in the August 10, 2022, online edition of the journal Advanced Functional Materials.
Related Links:
Terasaki Institute for Biomedical Innovation
Latest Molecular Diagnostics News
- Blood Proteins Could Warn of Cancer Seven Years before Diagnosis
- New DNA Origami Technique to Advance Disease Diagnosis
- Ultrasound-Aided Blood Testing Detects Cancer Biomarkers from Cells
- New Respiratory Syndromic Testing Panel Provides Fast and Accurate Results
- New Synthetic Biomarker Technology Differentiates Between Prior Zika and Dengue Infections
- Novel Biomarkers to Improve Diagnosis of Renal Cell Carcinoma Subtypes
- RNA-Powered Molecular Test to Help Combat Early-Age Onset Colorectal Cancer
- Advanced Blood Test to Spot Alzheimer's Before Progression to Dementia
- Multi-Omic Noninvasive Urine-Based DNA Test to Improve Bladder Cancer Detection
- First of Its Kind NGS Assay for Precise Detection of BCR::ABL1 Fusion Gene to Enable Personalized Leukemia Treatment
- Urine Test to Revolutionize Lyme Disease Testing
- Simple Blood Test Could Enable First Quantitative Assessments for Future Cerebrovascular Disease
- New Genetic Testing Procedure Combined With Ultrasound Detects High Cardiovascular Risk
- Blood Samples Enhance B-Cell Lymphoma Diagnostics and Prognosis
- Blood Test Predicts Knee Osteoarthritis Eight Years Before Signs Appears On X-Rays
- Blood Test Accurately Predicts Lung Cancer Risk and Reduces Need for Scans