FACT or PACT: A Comparison between Free-Acrylamide and Acrylamide-Based Passive Sodium Dodecyl Sulfate Tissue Clearing for whole Tissue Imaging


Huimei Wang, M.Sc, 1,#Arezoo Khoradmehr, M.Sc, 2,#Amin Tamadon, D.V.M., Ph.D, 3,*
Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institute of Acupuncture and Moxibustion, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
The Persian Gulf Marine Biotechnology Research Center, The Persian Gulf Biomedical Sciences Research Institute, Bushehr University of Medical Sciences, Bushehr, Iran
Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institute of Acupuncture and Moxibustion, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
The Persian Gulf Marine Biotechnology Research Center, The Persian Gulf Biomedical Sciences Research Institute, Bushehr University of Medical Sciences, Bushehr, Iran
*Corresponding Address: P.O.Box: 7514763448 The Persian Gulf Marine Biotechnology Research Center The Persian Gulf Biomedical Sciences Research Institute Bushehr University of Medical Sciences Bushehr Iran Email:amintamaddon@yahoo.com

The first two authors equally contributed to this work.

The Cell Journal (Yakhteh) is an open access journal which means the articles are freely available online for any individual author to download and use the providing address. The journal is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported License which allows the author(s) to hold the copyright without restrictions that is permitting unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited.
Wang Huimei, Khoradmehr Arezoo, Tamadon Amin. FACT or PACT: A Comparison between Free-Acrylamide and Acrylamide-Based Passive Sodium Dodecyl Sulfate Tissue Clearing for whole Tissue Imaging. Cell J. 2019; 21(2): 103-114.

Abstract

Major biological processes rely on the spatial organization of cells in complex, highly orchestrated three-dimensional (3D) tissues. Until the recent decade, most of information on spatial neural representation primarily came from microscopic imaging of “2D” (5-50 μm) tissue using traditional immunohistochemical techniques. However, serially sectioned and imaged tissue sections for tissue visualization can lead to unique non-linear deformations, which dramatically hinders scientists’ insight into the structural organization of intact organs. An emerging technique known as CLARITY renders large-scale biological tissues transparent for 3D phenotype mapping and thereby, greatly facilitates structure-function relationships analyses. Since then, numerous modifications and improvements have been reported to push the boundaries of knowledge on tissue clearing techniques in research on assembled biological systems. This review aims to outline our current knowledge on next-generation protocols of fast free-of-acrylamide clearing tissue (FACT) and passive CLARITY (PACT). The most important question is what method we should select for tissue clearing, FACT or PACT. This review also highlights how FACT differs from PACT on spanning multiple dimensions of the workflow. We systematically compared a number of factors including hydrogel formation, clearing solution, and clearing temperatures between free-acrylamide and acrylamide-based passive sodium dodecyl sulfate (SDS) tissue clearing and discussed negative effects of polyacrylamide on clearing, staining, and imaging in detail. Such information may help to gain a perspective for interrogating neural circuits spatial interactions between molecules and cells and provide guidance for developing novel tissue clearing strategies to probe deeply into intact organ.