Richard Dluhy,1 Amareshwari Konutham,1 Joo-Yeun Oh,2 Amit Gaggar,2 Rakesh Patel2
1Department of Chemistry, University of Alabama at Birmingham, Birmingham AL 35294 USA
2Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294 USA
Extracellular vesicles (EVs) are small (<300 nm) spherical nanoparticles released by a large
array of different cell types in response to stress or disease. EVs have been shown to play a significant role in a variety of intracellular communication pathways integral to both healthy and disease states. EVs are also potentially important as diagnostic biomarkers for e.g. cancer and neurodegenerative diseases. The scope of how EVs mediate disease is the subject of intense current interest in nanomedicine and theranostics.
Despite the increased focus on the biomedical importance of EVs, the extensive processing required for their isolation of EV nanoparticles makes routine biochemical analysis problematical. Vibrational spectroscopy, both IR and Raman, have been increasingly employed as an EV detection platform to overcome these challenges. We have investigated the development of a new class of molecular spectroscopic methods dedicated to EV diagnostics and have shown that vibrational imaging using Raman and IR can identify the differential effects of EVs on pulmonary epithelial cells. We have employed standard Raman and IR imaging methods to evaluate cellular phenotypes based on their vibrational band profiles. Clear biochemical differences were identified between control and treated cells. These studies identify Raman and IR microscopy as valuable noninvasive diagnostic modalities for the study of EV’s in relation to overall age-induced hemolysis and toxicity in RBCs.