A versatile clearing agent for multi-modal brain imaging

TL;DR

This paper introduces TDE, a versatile, cost-effective brain clearing agent that preserves fluorescence and is compatible with multiple imaging techniques, enabling comprehensive neuroanatomical mapping across various samples.

Contribution

The study presents TDE as a novel, adaptable clearing agent suitable for diverse imaging modalities and tissue types, enhancing neuroimaging capabilities.

Findings

Effective in whole mouse hippocampus imaging

Compatible with immunostaining and light sheet microscopy

Preserves fluorescence and tissue integrity

Abstract

Extensive mapping of neuronal connections in the central nervous system requires high-throughput um-scale imaging of large volumes. In recent years, different approaches have been developed to overcome the limitations due to tissue light scattering. These methods are generally developed to improve the performance of a specific imaging modality, thus limiting comprehensive neuroanatomical exploration by multimodal optical techniques. Here, we introduce a versatile brain clearing agent (2,2'-thiodiethanol; TDE) suitable for various applications and imaging techniques. TDE is cost-efficient, water-soluble and low-viscous and, more importantly, it preserves fluorescence, is compatible with immunostaining and does not cause deformations at sub-cellular level. We demonstrate the effectiveness of this method in different applications: in fixed samples by imaging a whole mouse hippocampus with serial two-photon tomography; in combination with CLARITY by reconstructing an entire mouse brain with light sheet microscopy and in translational research by imaging immunostained human dysplastic brain tissue.