Neurovascular Lesions
Team
Brigitte Onteniente: Research Director DR2 (INSERM)
Michel Cailleret : Research Engineer (INSERM)
Michel Cailleret : Research Engineer (INSERM)
Valérie Itier : Assistant Professor (University Paris 12)
Jerôme Polentes: Associate scientist (CECS)
Marion Brénot : Qualified research technician (CECS)
Olivier Chose : Associate scientist (CECS)
Marion Brénot : Qualified research technician (CECS)
Olivier Chose : Associate scientist (CECS)
Aims and background :
Ischemic stroke is a leading cause of death and long-term disability, and accounts for a large proportion of the health care costs in industrialized countries. Although stroke is mainly of polygenic origin, a large number of single-gene disorders such as hypercoagulable states, nonatherosclerotic vasculopathies and cardiac, hematologic, or connective disorders have been described as well-known causes of stroke. In addition, a number of monogenic stroke disorders exist that are related to small and large arterial abnormalities leading to stenosis, occlusion, and dissection of blood vessels. These include Cerebral Autosomal Dominant (CADASIL) and Recessive (CARASIL) Arteriopathy with Subcortical Infarcts and Leukoencephalopathy, hereditary endothelio-pathies, Fabry disease, pseudoxanthoma elasticum, type 1 neurofibromatosis, familial MoyaMoya disease, type IV Ehlers-Danlos syndrome, and the Marfan syndrome. Despite substantial research into cytoprotection, and a remarkable number of positive research results, no efficient agent has been shown conclusively to be clinically effective in acute NeuroVascular Lesions (NVL) to date. Our studies aim at defining new therapeutic strategies to decrease the clinical consequences and societal burden of cerebrovascular lesions. We currently focus on the therapeutic potential of pluripotent stem cell therapy – human Embryonic Stem (hES) cells and human induced Pluripotent Stem (hiPS) cells. To speed-up the translation of experimental data on hiPS-based cell therapy to the clinic, we also work on the possibiliy to derive hiPS cells using a non-viral, human recombinant protein-based, approach.
Strategy, means and methods :
Stem cell therapy for NVL
Neural stem cells from hES and hiPS cells are used for intracerebral transplantation of neural stem cells into rodent models of neurovascular lesions. The main readout, functional outcome, is associated to imaging, to fit with clinical settings, and to post-mortem histological analysis. Functional and imaging evaluations are correlated with histological follow-up of the survival, integration and interactions of transplanted cells with the host brain.
Schematic representation of the experimental procedures
TAT-fusion proteins for hiPS (TiPS) Based on previous know-how on recombinant proteins fused to the HIV1-TAT transduction domain, we aim at optimizing the derivation of hiPS cells with direct use of Transcription Factors (FT). TAT-FTs are produced in human HEK cells, purified with Fast Protein Liquid Chromatography (FPLC) and applied to human fibroblasts with varying cocktails of helper small molecules.
Results and future prospects :
Stem cell therapy for NVL Our results provided the proof-of-concept hES cells- and hiPS cells-derived therapy in NVL. Neural progenitors derived from both cell sources generated homotopical neuronal populations fully integrated into the host brain in terms of neurochemical phenotype and topology of projections. We also demonstrated the total absence of side-effects or threatening structures by transplanted cells, indicating the safety of the approach.
Diverse populations of GABAergic neurons formed by hiPS-derived neural progenitors are observed in grafts
TAT-fusion proteins for hiPS (TiPS)
The five main TFs involved in pluripotency and self-renewal have been successfully produced as TAT-fusion proteins. Preliminary results show the feasibility of reprogramming human fibroblasts based on this strategy. A combinatorial study using varying TF stoichiometries with small molecules is ongoing.
Publications :
Heurteaux C et al., Neuroprotective and neuroproliferative activities of NeuroAid (MLC601, MLC901), a Chinese Medicine, in vitro and in vivo. Neurophar-macology. 2010 Jun;58(7):987-1001. Seminatore C et al., The post-ischemic environment differentially impacts teratoma or tumour formation following transplantation of human embryonic stem cells-derived neural progenitors. Stroke. 2010 Jan;41(1):153-9. Souktani R et al., Cardioprotection against myocardial infarction with PTD-BIR3/ RING, a XIAP mimicking protein. J Mol Cell Cardiol. 2009 May;46(5):713-8. Guégan C et al., PTD-XIAP fusion proteins protect against cerebral ischemia by anti-apoptotic and transcriptional regulatory mechanisms. Neurobiol Dis. 2006;22:177-186.
Patent :
WO/2007/039254 (2007-04-12) and US2009/0118180 A1 (May 7, 2009)
ONTENIENTE, Brigitte; (FR). GUEGAN, Christelle; (FR). BRAUDEAU, Jérôme; (FR). COURIAUD, Cécile; (FR).
Use of fusion protein for the prevention or the treatment of pathologies resulting from ischemia 