Label‐Free Myelin Fingerprinting: An Adult Human Post‐Mortem Brain Slice Platform via Coherent Anti‐Stokes Raman Spectroscopy

ABSTRACT Animal models and simple cell cultures often lack sufficient overlap with human physiology to study human neurological conditions effectively; one emerging alternative is the use of human organotypic slice cultures (OSCs). This study shows, using viability studies, post‐mortem corpus callosum (CC) tissue OSCs cultured with a chemically defined serum‐free culturing medium, maintaining viability for at least 8 days in vitro (DIV). The inclusion of CC simplifies myelin‐focused research, and its potential is highlighted by visualizing molecular information within myelin by the use of label‐free Coherent anti‐Stokes Raman spectroscopy (CARS) imaging. This study delineates a window of 32 h after time of death (TOD) wherein myelin remains unaffected from base measurements. Finally, as a proof‐of‐concept, the CC tissue of a human‐specific disease characterized by myelin degeneration, multiple sclerosis (MS), reveals signs of altered myelin spectral profiles when compared to non‐MS myelin. In conclusion, this study provides characterization of the development of a human myelin model in combination with a CARS‐focused method of analysis, establishing it as a novel toolset for future research of myelin‐based neurological conditions.