Induced Tauopathy in a Novel 3D-Culture Model Mediates Neurodegenerative Processes: A Real-Time Study on Biochips Diana Seidel1., Dana Krinke1., Heinz-Georg Jahnke1, Anika Hirche2, Daniel Kloß 1 , Till G. A. Mack3,4, Frank Striggow3,4, Andrea Robitzki1* 1 Centre for Biotechnology and Biomedicine (BBZ), University of Leipzig, Division of Molecular Biological-Biochemical Processing Technology, Leipzig, Germany, 2 Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig, Germany, 3 KeyNeurotek Pharmaceuticals AG, Zenit Technologiepark, Magdeburg, Germany, 4 Department of Neurodegeneration and Intervention Strategies, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany Abstract Tauopathies including Alzheimer’s disease represent one of the major health problems of aging population worldwide. Therefore, a better understanding of tau-dependent pathologies and consequently, tau-related intervention strategies is highly demanded. In recent years, several tau-focused therapies have been proposed with the aim to stop disease progression. However, to develop efficient active pharmaceutical ingredients for the broad treatment of Alzheimer’s disease patients, further improvements are necessary for understanding the detailed neurodegenerative processes as well as the mechanism and side effects of potential active pharmaceutical ingredients (API) in the neuronal system. In this context, there is a lack of suitable complex in vitro cell culture models recapitulating major aspects of taupathological degenerative processes in sufficient time and reproducible manner. Herewith, we describe a novel 3D SH-SY5Y cell-based, tauopathy model that shows advanced characteristics of matured neurons in comparison to monolayer cultures without the need of artificial differentiation promoting agents. Moreover, the recombinant expression of a novel highly pathologic fourfold mutated human tau variant lead to a fast and emphasized degeneration of neuritic processes. The neurodegenerative effects could be analyzed in real time and with high sensitivity using our unique microcavity array-based impedance spectroscopy measurement system. We were able to quantify a time- and concentration-dependent relative impedance decrease when Alzheimer’s disease-like tau pathology was induced in the neuronal 3D cell culture model. In combination with the collected optical information, the degenerative processes within each 3D-culture could be monitored and analyzed. More strikingly, tau-specific regenerative effects caused by tau-focused active pharmaceutical ingredients could be quantitatively monitored by impedance spectroscopy. Bringing together our novel complex 3D cell culture taupathology model and our microcavity array-based impedimetric measurement system, we provide a powerful tool for the label-free investigation of tau-related pathology processes as well as the high content analysis of potential active pharmaceutical ingredient candidates. Citation: Seidel D, Krinke D, Jahnke H-G, Hirche A, Kloß D, et al. (2012) Induced Tauopathy in a Novel 3D-Culture Model Mediates Neurodegenerative Processes: A Real-Time Study on Biochips. PLoS ONE 7(11): e49150. doi:10.1371/journal.pone.0049150 Editor: Akio Suzumura, Research Institute of Environmental Medicine - Nagoya University, Japan Received May 25, 2012; Accepted October 4, 2012; Published November 7, 2012 Copyright: 2012 Seidel et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was funded by the German Research Foundation (DFG; SFB610, T1 Rob.). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Till G.A. Mack and Frank Striggow were formerly employed by the the KeyNeurotek Pharmaceuticals AG. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials. * E-mail: andrea.robitzki@bbz.uni-leipzig.de . These authors contributed equally to this work. Introduction Today, more than 35 million patients are suffering from dementia including Alzheimers disease (AD) [1] and there are estimations that the number of AD cases will further rise to more than 100 million in 2050 [2,3]. Therefore, a detailed understand- ing of the underlying mechanisms leading to disease onset and progression is essential to develop novel therapeutic strategies. Extracellular b amyloid (Ab) plaques and intracellular tau fibrils are the two hallmarks of AD pathology. In the past, the majority of AD-related active pharmaceutical ingredients (API) development programs were focused on Ab. More recently, accumulating evidence has suggested that both, Ab and tau might be involved in the initiation, manifestation and progression of AD [4,5,6]. However, the molecular mechanisms that may link Ab- and tau- induced signaling cascades and underlie AD are still not completely known. An insufficient molecular understanding of AD pathology itself as well as inappropriate preclinical disease and screening models are likely a substantial cause for many failures in clinical active pharmaceutical ingredients (API) development in AD over the past years [7]. In this context, we have developed a novel 3D in vitro cell culture model, which is based on the human neuroblastoma cell line SH-SY5Y that have been previously used in several tau pathology studies [8,9,10]. However, the use of spheroid cultures, instead of monolayer cultures, might be preferred, since 3D cultures recapitulate the in vivo situation likely better than 2D cell PLOS ONE | www.plosone.org 1 November 2012 | Volume 7 | Issue 11 | e49150