Profiling of Oral Cells Morphology by means of a novel Label-Free Method of Polarization Diffraction Imaging

Currently, all oral leukoplakias, per gold standard, should undergo microscopic examination for diagnosis, which is an invasive procedure, and many patients are resistant to it due to cost, fear, or aversion to pain. We plan to develop a non-invasive assay, by using polarization diffraction imaging flow cytometry (p-DIFC) which is a technique that renders a three-dimensional model of single cells. That acquires a cross-polarized diffraction image pair (p-DI) of the coherent light scattered by a single cell with high image contrast excited by a linearly polarized laser beam. This method of single-cell assay enables extraction of cell morphology related information from the diffraction patterns embedded in the p-DI pair for each individual cell. In addition, the team has developed an optical model of cells based on confocal imaging to simulate the coherent light scattering process of a cell and convert the spatial distribution of scattered light into calculated p-DI pairs. Objectives: We aim to develop a protocol for acquiring oral mucosal cells for confocal imaging and establishing their individual three-dimensional (3D) morphologic profiles in the form of a preliminary database. In Phase 2, we will establish correlations between diffraction patterns from calculated p-DI data and the morphologic features revealed by mi- croscopy. Methods: We are collecting and quantifying individual cells from oral mucosa, in order to set a quantitative 3D morphologic single-cell parameter by confocal microscopy, for modeling study of diffraction patterns. Phase 2 of the study will involve single-cell analysis using p-DIFC for identification of early malignant changes in cytological sampling of mucosal lesions suspicious for malignancy. Conclusions: The results of this ongoing investigation will lay the foundation for future non-invasive, label-free detection of precancerous cells during intraoral examination, by investigating the profiling of cells harvested from patients in our institutions.