Molecular imaging of neural stem cell differentiation - a novel quantitative and noninvasive approach using imaging reporters

• Applicant: Dr. Markus Aswendt, since 4/2016
• Subject Area: Molecular and Cellular Neurology and Neuropathology
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 253412843

Stroke, dementia and Parkinson´s disease belong to the most common neurological disorders. The established therapies, however, cannot reverse the characteristic and progressive neuronal cell loss and the resulting functional deficits. Research on stem cells can contribute substantially to reveal the molecular principles of neurological disorders and to the development of novel therapies. In particular neural stem cells represent a promising resource due to their ability to differentiate into all neurons and glial cells of the central nervous system. The project described here is based on our expertise in molecular imaging of stem cell-based regeneration in stroke. Our goal is to establish a molecular imaging platform for noninvasive and quantitative cell fate imaging. For this purpose, we generated neural stem cells including a set of imaging reporters under control of a constitutive or cell-specific promoter. Undifferentiated and differentiated cells are distinguished by the specific reporter set due to the constitutive and cell-specific promoter activity. Compared to invasive methods, molecular imaging offers the key advantage of monitoring the time profile profile of cell viability, cell fate and the therapeutic effect. We successfully applied this concept in a pilot study to monitor the glial differentiation of murine neural stem cells in vitro and in vivo. The constitutive bioluminescence and fluorescence reporters are distinguished from the astrocyte-specific ones by a selective bioluminescence substrate and the fluorescence emission spectra, respectively. Furthermore, the constitutive bioluminescence signal is used for normalization to the number of viable cells, whereas the astrocyte-specific signal monitors the differentiation process. Fluorescence imaging was used to distinguish the two cell states, undifferentiated and differentiated, in accordance with immunostainings. As part of the proposal described here, the imaging platform will be extended and validated to target a variety of neuronal, astroglial and oligodendroglial cell types. A further aim will be to identify substances with pro-neuronal and pro-glial effects. The imaging platform will provide for the first time insight into the cellular functions underlying stem cell recovery processes in neurological disorders.

• DFG Programme: Research Grants
• Ehemalige Antragstellerin: Dr. Annette Tennstädt, from 1/2015 until 4/2016