Christelle Monville: Professor (UEVE)
Walter Habeler: Research associate (CECS)
Alexandra Plancheron: Qualified research technician (CECS)
Karim Ben M’Barek : Post-doctoral fellowship (DIM Biotherapies)
Aims and background:
The retina contains photoreceptors that convert light signals into electric signals, further transmitted to the brain by different neurons. Any defect involved in these processes of phototransduction and transmission in the retina lead to visual impairment. Retinal degenerative diseases, including age-related macular degeneration and Retinitis Pigmentosa (RP) are the predominant causes of human blindness worldwide and are very difficult to treat. While clinical trials based on gene therapy are imminent for few genetically characterized sub-groups of patients, the overall genetic heterogeneity implies that diverse therapeutic approaches need to be developed. The accessibility of the retina, together with imaging technologies makes it a prime candidate for developing cellular therapies for central nervous disorders. In the context of cell therapy, the pluripotent status of human Embryonic Stem (hES) cells suggests that these cells could be used as an unlimited source of partially or fully differentiated retinal cells for tissue transplantation and cellular therapy.
The objectives of our group are to develop pre-clinical studies required for the development of human pluripotent stem cells cellular therapy for the treatment of a number of retinal diseases.
Furthermore, the generation of induced Pluripotent Stem (iPS) cells from an individual RP patient would enable the large-scale production of the cell types affected by the patient’s disease. Although traditional cell replacement remains a central goal in applied stem cell research, the derivation of patient-specific iPS cells might be equally useful for disease-related research. Indeed, these cells could in turn be used for disease modelling and drug discovery.
Strategy, means and methods:
The first step of our program is to apply the previously established lab-culture conditions that first commit human ES (hES) and iPS cells into retinal precursors. The second step will be to optimize culture conditions for the commitment of the iPS/hES cell-derived retinal precursors towards the photoreceptor lineage. Molecular characterization (transcriptomic analysis, surface antigen investigation…) and in vitro transplantation studies will be performed on this population (photoreceptor precursor) corresponding to cells that had a great capability to integrate and differentiate into retina.
The last part of our program is based on the fact that iPS cell lines which express a disease-related mutant gene could represent a relevant human cellular model for disease modeling and drug screening. These customised iPS cells from RP patients will be use to characterize molecular mechanisms underlying photoreceptor apoptosis and to determine molecular signature due to the presence of mutations.
Results and future prospects:
Our first results demonstrate our ability to produce retinal precursors (even at a low yield) and mainly Retinal Pigment Epithelial (RPE) cells at a high yield (99%) from hES and iPS cells. We are now in the process of improving these protocols using reporter cell lines in order to follow precisely the differentiation steps towards photoreceptor precursors.
In parallel, we have generated iPS cell lines from fibroblasts of two patients (Coriell) suffering from Leber Congenital Amaurosis (LCA). Transcriptomic analyses comparing normal and mutated RPE-derived from iPS cells are ongoing and will enable us to discover biomarkers for this pathology and to set up a drug screening test.
- Habeler W et al., Organotypic heart slices for cell transplantation and physiological studies. Organogenesis. 2009;5(2):62-66.
- Habeler W et al., An in vitro beating heart model for long-term assessment of experimental therapeutics. Cardiovasc Res. 2009;81(2):253-9.
PESCHANSKI, MARC; (FR). HABELER, Walter; (FR). MONVILLE, Christelle; (FR).
An in vitro beating heart model.
- Dr. Olivier Goureau and Dr Emeline Nandrot, IDV, Inserm UMR S968, Paris, France, (ANR GPiPS)
- Pr. Stéphane Blot, Laboratoire de Neuroscience, ENVA, Maisons-Alfort, France, (ANR Cardiostem)
- Dr. Bijan Ghaleh and Pr Alain Berdeaux, Inserm U955, Créteil, France, (ANR Cardiostem)
- Dr. Didier Letourneur and Dr Catherine Levisage, Inserm U698, Paris, France, (Utilisation de Matrices Biodégradables pour la culture et la greffe de cellules dérivées des hES)