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bioRxiv · 10.1101/680702

A novel decellularization method to produce brain scaffolds

Abstract

Scaffolds composed of extracellular matrix (ECM) can assist tissue remodeling and repair following injury. The ECM is a complex biomaterial composed of proteins, glycoproteins, proteoglycans, and glycosaminoglycans, secreted by cells. The ECM contains fundamental biological cues that modulate cell behavior and serves as a structural scaffold for cell adhesion and growth. For clinical applications, where immune rejection is a constraint, ECM can be processed using decellularization methods intended to remove cells and donor antigens from tissue or organs, while preserving native biological cues essential for cell growth and differentiation. Recent studies show bioengineered organs composed by a combination of a diversity of materials and stem cells as a possibility of new therapeutic strategies to treat diseases that affect different tissues and organs, including the central nervous system (CNS). Nevertheless, the methodologies currently described for brain decellularization involve the use of several chemical reagents with many steps that ultimately limit the process of organ or tissue recellularization. Here, we describe for the first time a fast and straightforward method for complete decellularization of mice brain by the combination of rapid freezing and thawing following the use of only one detergent (Sodium dodecyl sulfate (SDS)). Our data show that using the protocol we describe here the brain can be entirely decellularized, while still maintaining ECM components that are essential for cell survival and repopulation of the scaffold. Our results also show the repopulation of the decellularized brain matrix with Neuro2a cells, that were identified by immunohistochemistry in their undifferentiated form. We conclude that this novel and simple method for brain decellularization can be used as a biocompatible scaffold for cell repopulation.\n\nImpact StatementFor the first time we describe an easy, effective and low cost method for complete decellularization of murine brain by the use of only one detergent (SDS) combined with rapid freezing and thawing, that can be used as a 3D scaffold for cell culture of neuronal cells. The results show that the decellularized brains still maintain ECM components essential for cell survival and repopulation of the scaffold. Moreover, we found that the decellularized brain matrix can be repopulated with neural cells, showing its biocompatibility.\n\nGRAFICAL ABSTRACT\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC=\"FIGDIR/small/680702v1_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (26K):\norg.highwire.dtl.DTLVardef@15fd027org.highwire.dtl.DTLVardef@15acfeborg.highwire.dtl.DTLVardef@1087d2eorg.highwire.dtl.DTLVardef@529309_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Granato, A. E. C., da Cruz, E. F., Rodrigues-Junior, D. M., Mosini, A. C., Cheffer, A., Porcionatto, M., Ulrich, H.. 2019-06-24. A novel decellularization method to produce brain scaffolds. https://doi.org/10.1101/680702

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