In this study, the investigators propose, for the first time, to test the safety and the potential efficacy of repeated allogenic Adipose tissue-derived Mesenchymal Stromal Cells (ASCs) IT injections in Primary Progressive Multiple Sclerosis (PPMS) patients. In fact, even if autologous Bone Marrow-Mesenchymal Stromal Cells (BM-MSC) and ASCs have already been infused intrathecally in multiple sclerosis, repeated injections of allogenic ASCs have never been tested in this disease. The use of allogenic cells is driven by recent publications reporting decreased suppressive properties of autologous MSC from MS patients.
The hypothesis is that 3 repeated intrathecal (IT) injections of allogenic ASCs every 3 months will be safe and can lower disease progression in PPMS patients.
Preamble of infusing ASCs in the first patient, it's necessary to constitute and characterize the ASC bank. ASC will be obtained from Allogeneic human mesenchymal stromal cells derived from adipose tissue of a living donor.
Once the bank is available, MS patients will be screened and included in Rennes university hospital to received ASC's infusions.
MS patients will be followed for one year after inclusion
