Andreas Hermann

Characterization and manipulation of the stem cell niche in the adult midbrain.
Since the early 90ies neurogenesis in the adult mammalian brain is well known. However, this is restricted to two regions within the adult brain, namely the subventricular zone (SVZ) of the lateral ventricles as well as the dentate gyrus (DG) of the hippocampus. We recently showed the excistance of neural stem cells (NSCs) also in the midbrain. In contrast to NSCs from the SVZ or the DG these midbrain-derived adult NSCs can be differentiated to functional dopaminergic neurons. However, these midbrain NSCs do not proliferate in vivo representing most likely dormant progenitor cells (Hermann 2006a, 2009).
The aim of our work is to elucidate whether the differences between midbrain-derived NSCs and NSCs from the SVZ or DG are due to cell intrinsic mechanisms or whether cell extrinsic signals from the surrounding brain tissue suppress in vivo neurogenesis in the midbrain. Furthermore our efforts focus on manipulation of the stem cell niche within the midbrain aiming on the activation of these dormant NSCs as a cell source for endogenous cell replacement strategies, e.g. in Parkonson’s disease (Hermann 2008).
 
 
Characterization of adult neural stem cells within the adult human brain.
Adult neurogenesis in the human brain was finally proven in the early 90ies. Interestingly, the human neurogenic regions differ from their mouse counterparts. This is most obvious in the architecture of the human subventricular zone (SVZ) of the lateral ventricles. Major differences are decreased rapid amplifying cells as well as a representative bulbus olfactorius as target for the newly generated neurons. Of note is however the discovery of progenitor cells within the white matter, so called oligodenrocyte progenitor cells (OPCs). These are easy to isolate and behave like typical NSCs in vitro generating astrocytes, oligodendrocytes and neurons. We recently showed that most of NSCs isolated from the adult human hippocampus are such OPCs. Since these cells are already regionalized, possessing properties of the region of isolation, these hippocampal NSCs cannot produce dopamine nerve cells (Hermann 2006b, Maisel 2007).
The aim of our work is the exact characterization of these OPCs-NSCs from the human brain in vivo and in vitro. A special focus is drawn on transcription factors involved in neuronal differentiation (e.g. SOX2, OLIG2). Futhermore we are working on approaches for manipulation of these human NSCs to become dopamine neurons. Thereby these human NSCs might be a potential cell source for autologous cell replacement therapies for example in Parkinson’s disease.

 
Name:Andreas Hermann
Born:4th August, 1978
 
Education:
Februar, 2007
PhD defense (Doktor der biomedizinischen Wissenschaften /Dr. rer. med.) about: “In vitro neurogenesis of adult neural stem cells from bone marrow and brain.“ University of Ulm, Germany
October, 2005 Approbation as medical doctor, Dresden University of Technology, Germany

 
 
Research and Clinical Experience:

01/2007-07/09 Seed grant of the Center for Regenerative Therapies Dresden (CRTD)
12/2005- present Resident in the Department of Neurology, Technical University Dresden
10/2004- present Research in Experimental Neurology, Technical University Dresden, Research group Neurodegeneration and Neuroregeneration (group leader: Prof. Alexander Storch, M.D.)
8/03-11/03
Practical course about “Mouse and human embryonic stem cell culture including
dopaminergic differentiation and transplantation in animal models of Parkinson’s disease” in the Molecular Biology Laboratories of Kwang-Soo Kim, McLean Hospital, Harvard Medical School, Boston, MA, USA

 

Literatur:

Meyer AK, Longin CF, Klose C, Hermann A. New regulator for energy signaling pathway in plants highlights conservation among species. Sci Signal. 2010 Apr 27;3(119):jc5.
Hermann A, Suess C, Fauser M, Kanzler S, Witt M, Fabel K, Schwarz J, Höglinger GU, Storch A.Rostro-Caudal Gradual Loss of Cellular Diversity Within The Periventricular Regions of The Ventricular System. Stem Cells, 2009;Accepted Article Online: DOI: 10.1002/stem.21
 
Hermann A, Storch A. Endogenous regeneration in Parkinson's disease: do we need orthotopic dopaminergic neurogenesis?Stem Cells, 2008; 26(11):2749-5
 
Maisel M, Herr A, Milosevic J, Hermann A, Habisch HJ, Schwarz S, Kirsch M, Antoniadis G, Brenner R, Hallmeyer-Elgner S, Lerche H, Schwarz J, Storch A. Transcription profiling of adult and fetal human neuroprogenitors identifies divergent paths to maintain the neuroprogenitor cell state. StemCells, 2007, 2007 May;25(5):1231-40
 
Hermann A, Maisel M, Liebau S, Gerlach M, Kleger A, Schwarz J, Kim KS, Antoniadis G, Lerche H, Storch A: Mesodermal cell types induce neurogenesis from adult human hippocampal progenitor cells. Journal of Neurochemistry, 2006; 98(2): 629-640.
 
Hermann A, Maisel M, Wegner F, Liebau S, Kim DW, Gerlach M, Schwarz J, Kim KS, Storch A: Multipotent Neural Stem Cells from the Adult Tegmentum with Dopaminergic Potential Develop Essential Properties of Functional Neurons. Stem Cells 2006, 24(4): 949-64.