Development of Physiologically Human-Relevant in vitro Brain Environment with Brain Decellularized Extracellular Matrix

Abstract

In vitro model for neurodegenerative disease research has emerged to supplement the limitation of existing clinical in vivo model, regarding to recapitulation of human disease pathophysiology. However, the conventional in vitro models like 2D cell culture on a dish are restricted to mimic physiological environment, including components of extracellular matrix and stiffness of the native brain, which are lack in artificial culture materials. The features are essential to reproduce pathophysiology and biological characteristics of the disease models. In order to reconstruct the physiological native brain environment on 3D in vitro, we developed a brain decellularized extracellular matrix (BdECM) bioink. In brief, we isolated a porcine brain and washed the tissue with various solutions to remove cellular components and maintain extracellular matrix of the brain. Proteomics analysis showed that BdECM has protein components of basal lamina in the brain, including collagen and laminin. We also performed rheological analysis for solubilized BdECM bioink to find physiologically similar stiffness to the native brain. In addition to that, neural cells were employed to see the biological potential for 3D microenvironment. Microglia and neural progenitor cells were cultured on BdECM bioink. The cells showed enough cell viability and no immune response for microglia, confirmed with microglia activation marker. We have successfully developed BdECM to recapitulate physiological environment of the native brain, verifying stiffness and components analysis. We will apply the material for reconstruction of native brain environment and disease research.