Original Article

Exp Neurobiol 2019; 28(3): 436-445

Published online June 26, 2019

© The Korean Society for Brain and Neural Sciences

FxClear, A Free-hydrogel Electrophoretic Tissue Clearing Method for Rapid De-lipidation of Tissues with High Preservation of Immunoreactivity

Jungyoon Choi, Eunsoo Lee, June Hoan Kim, and Woong Sun*

Department of Anatomy and Division of Brain Korea 21 Plus Program for Biomedical Science, Korea University College of Medicine, Seoul 02841, Korea.

Correspondence to: *To whom correspondence should be addressed.
TEL: 82-2-2286-1404, FAX: 82-2-929-5696
Two authors contributed equally to this study

Received: March 10, 2019; Revised: April 19, 2019; Accepted: May 10, 2019

Over the last two decades, several tissue clearing methodologies have been established that render tissues optically transparent and allow imaging of unsectioned tissues of significant volumes, thus improving the capacity to study the relationships between cell and 3D tissue architecture. Despite these technical advances, the important unsolved challenges that these methods face include complexity, time, consistency of tissue size before and after clearing, and ability to immunolabel various antibodies in cleared tissue. Here, we established very simple and fast tissue clearing protocol, FxClear, which involves acrylamide-free electrophoretic tissue clearing (ETC). By removal of the acrylamide infusion step, we were able to achieve fast reaction time, smaller tissue expansion, and higher immunoreactivity. Especially, immunoreactivity and fluorescence intensity were increased in FxClear-processed tissues compared to un-cleared tissues. Our protocol may be suitable for small-sized biopsy samples for 3D pathological examinations.

Graphical Abstract

Keywords: Three dimensional imaging, Immunohistochemistry, Tissue engineering, Brain tissue