03/05/2025
By Amanda Vozzo
Date: Wednesday, March 19, 2025
Time: 4-5 p.m.
Location: Olsen Hall, Room 503
Lev T. Perelman, Harvard University, will give a talk on “Multispectral Light Scattering Imaging for Precancer Detection and Cell Analysis”
Abstract: Optical spectroscopy is a powerful tool for studying live tissue and detecting early disease. While fluorescence and Raman spectroscopy reveal molecular composition, light scattering spectroscopy, arising from the extracellular matrix and subcellular structures, provides insights into tissue organization. This talk will explore how multispectral light scattering imaging enables noninvasive precancer detection in diverse organs like the esophagus, pancreas, and bile duct. Despite their differences, many precancers share features such as larger nuclei and a higher concentration of epithelial cells, producing distinctive light scattering signatures for early detection without external markers. Beyond cancer detection, these signatures offer insight into subcellular structures, including chromatin packing and organelle organization. Since nanoscale nuclear changes drive genetic alterations and neoplasia, label-free, nanoscale-sensitive tools are crucial. We’ll discuss how combining confocal microscopy with light scattering spectroscopy offers a novel, noninvasive approach with key advantages over existing methods.
Bio: Lev T. Perelman is Mary Tolan and Edward Grzelakowski Endowed Chair, Professor of Medicine, and Director of the Center for Advanced Biomedical Imaging and Photonics at Harvard University and Beth Israel Deaconess Medical Center. He is known for his work on application of optics and spectroscopy to life sciences and developmental and cell biology. His group pioneered biomedical light scattering spectroscopy (LSS) for noninvasive detection of early precancerous changes in epithelial tissues and tissue characterization. This technique was later extended to subcellular scales with development of confocal light absorption and scattering spectroscopic (CLASS) microscopy for label-free subcellular functional imaging, sensing chromatin packing in live cells, and demonstrating that exosomes promote tumorigenesis. Perelman's other contributions include demonstration of the world's first single-molecule detection with surface-enhanced Raman spectroscopy (SERS) and explanation of the critical role of stress confinement in short pulse laser ablation and laser surgery.