Validation of a Process for the Manufacture of Stem Cells Isolated From the Nasal Cavity for Innovative Cell Therapy of Traumatized Peripheral Nerves

Despite progress in the time taken to take charge and in the quality of the surgical technique, the repair of damaged peripheral nerves has not improved in the last twenty years. Faced with these limitations of surgical treatment, multidisciplinary teams from Marseille and Rouen have come together to propose an innovative approach to cell therapy that can limit inflammation and improve axonal growth.

Cell transplantation now appears as an alternative to treat nerve damage. Scientific advances have shown in animal models as well as in humans that mesenchymal stem cells are good cellular candidates for supporting nerve regeneration after transplantation. On the other hand, their collection requires an invasive sample most often of bone marrow. A new stem cell candidate capable of stimulating nerve regeneration has recently been identified in the olfactory mucosa located in the nasal cavity. These cells are part of the "ecto-mesenchymal" stem cell family. They have biological characteristics very similar to those of mesenchymal stem cells of the bone marrow.

They exhibit high mitogenic activity and have a high potential for differentiation towards neural lineages. Given their properties and ease of access within the nasal cavity, ecto-mesenchymal stem cells offer new perspectives for cell therapy targeting nerve damage.

In this context, nasal ecto-mesenchymal stem cells represent an interesting reconstruction alternative, particularly in the indication of peripheral nerve lesions. They are directly and easily accessible to any individual. We therefore propose in this study to validate a method of manufacturing isolated stem cells from a biopsy of a few cubic millimeters of the nasal cavity of adults, taken during a surgical procedure, with a view to proposing shortly an innovative cell therapy. From each nasal biopsy taken, the cells will be amplified in vitro under pharmaceutical grade conditions and then controlled, validated and characterized in particular for their ability to differentiate into neural cells and for their lack of genetic instability. The cells will also be cryo-preserved and then thawed under pharmaceutical grade conditions in order to validate the maintenance of their quality after cryopreservation allowing to propose a delayed implantation according to the clinical context. This study requires the taking of 25 biopsies of nasal mucosa taken from adults to document the reproducibility of the manufacturing process and possible inter-donor variations. This validation data is an essential step before considering a clinical trial of Innovative Cell Therapy Drugs.