Efficient and Fast Immuno-Labeling of Clarified Tissues Using Low-Field Enhanced Diffusion

To alleviate the severe limitation of the prohibitively long process of immune-fluorescence labeling on the routine applications of revolutionary intact tissue clearing techniques in diverse biomedical arenas.

We proposed an easily adaptable approach, electro-enhanced rapid staining (EERS), for highly efficient and fast immuno-labeling of thick clarified tissues. In EERS, an optimized and precisely controlled weak external electric field is engineered into a compact device to enable efficient and uniform transport of antibodies into clarified tissues while minimizing the detrimental effect of macromolecular crowding at the tissue-solution interface.

The experimental results show that, with EERS, a current density of only ∼0.2 mA mm^-2 is sufficient to achieve uniform labeling of clarified tissues of several millimeters thick in a few hours without detectable tissue damage. In addition, the amount of antibodies required is also several-fold lower than conventional immuno-labeling assays under comparable conditions.

It is expected that the implementation of EERS in most laboratories should significantly expedite the application of tissue clearing in a broad range of research explorations, both basic and clinical.