Traumatic spinal cord injuries (SCIs) often result in sensory, motor, and vegetative function loss below the injury site. Although preclinical results have been promising, significant solutions for SCI patients have not been achieved through translating repair strategies to clinical trials. In this study, we investigated the effective potential of mechanically activated lipoaspirated adipose tissue when transplanted into the epicenter of a thoracic spinal contusion. Male Sprague Dawley rats were divided into three experimental groups: SHAM (uninjured and untreated), NaCl (spinal cord contusion with NaCl application), and AF (spinal cord contusion with transplanted activated human fat). Pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) were measured to assess endogenous inflammation levels 14 days after injury. Sensorimotor recovery was monitored weekly for 12 weeks, and gait and electrophysiological analyses were performed at the end of this observational period. The results indicated that AF reduced endogenous inflammation post-SCI and there was a significant improvement in sensorimotor recovery. Moreover, activated adipose tissue also reinstated the segmental sensorimotor loop and the communication between supra- and sub-lesional spinal cord regions. This investigation highlights the efficacy of activated adipose tissue grafting in acute SCI, suggesting it is a promising therapeutic approach for spinal cord repair after traumatic contusion in humans.

The olfactory ecto-mesenchymal stem cell (OE-MSC) are mesenchymal stem cells originating from the lamina propria of the nasal mucosa. They have neurogenic and immune-modulatory properties and showed therapeutic potential in animal models of spinal cord trauma, hearing loss, Parkinsons’s disease, amnesia, and peripheral nerve injury. In this paper we designed a protocol that meet the requirements set by human health agencies to manufacture these stem cells for clinical applications. Once purified, OE-MSCs can be used per se or expanded in order to get the extracellular vesicles (EV) they secrete. A protocol for the extraction of these vesicles was validated and the EV from the OE-MSC were functionally tested on an in vitro model. Nasal mucosa biopsies from three donors were used to validate the manufacturing process of clinical grade OE-MSC. All stages were performed by expert staff of the cell therapy laboratory according to aseptic handling manipulations, requiring grade A laminar airflow. Enzymatic digestion provides more rapidly a high number of cells and is less likely to be contaminated. Foetal calf serum was replaced with human platelet lysate and allowed stronger cell proliferation, with the optimal percentage of platelet lysate being 10%. Cultivated OE-MSCs are sterile, highly proliferative (percentage of CFU-F progenitors was 15,5%) and their maintenance does not induce chromosomal rearrangement (karyotyping and chromosomal microarray analysis were normal). These cells express the usual phenotypic markers of OE-MSC. Purification of the EVs was performed with ultracentrifugation and size exclusion chromatography. Purified vesicles expressed the recognized markers of EVs (Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines) and promoted cell differentiation and neurite elongation in a model of neuroblastoma Neuro2a cell line. We developed a safer and more efficient manufacturing process for clinical-grade olfactory stem cells, these cells can now be used in humans. A phase I clinical trial will begin soon.An efficient protocol for the purification of the OE-MSC EVs have been validated. These EVs exert neurogenic properties in vitro . More studies are needed to understand the exact mechanisms of action of these EVs and prove their efficacy and safety in animal models.