Primary Olfactory Ensheathing Cell Culture from Human Olfactory Mucosa Specimen

Application and challenges of olfactory ensheathing cells in clinical trials of spinal cord injury

Spinal cord injury (SCI) can lead to severe motor, sensory and autonomic nervous dysfunction, cause serious psychosomatic injury to patients. There is no effective treatment for SCI at present. In recent years, exciting evidence has been obtained in the application of cell-based therapy in basic research. These studies have revealed the fact that cells transplanted into the host can exert the pharmacological properties of treating and repairing SCI. Olfactory ensheathing cells (OECs) are a kind of special glial cells. The application value of OECs in the study of SCI lies in their unique biological characteristics, that is, they can survive and renew for life, give full play to neuroprotection, immune regulation, promoting axonal regeneration and myelination formation. The function of producing secretory group and improving microenvironment. This provides an irreplaceable treatment strategy for the repair of SCI. At present, some researchers have explored the possibility of treatment of OECs in clinical trials of SCI. Although OECs transplantation shows excellent safety and effectiveness in animal models, there is still lack of sufficient evidence to prove the effectiveness of their clinical application in clinical trials. There has been an obvious stagnation in the transformation of OECs transplantation into routine clinical practice, and clinical trials of cell therapy in this field are still facing major challenges and many problems that need to be solved. Therefore, this paper summarized and analyzed the clinical trials of OECs transplantation in the treatment of SCI, and discussed the problems and challenges of OECs transplantation in clinical trials.

Combined treatment of retinoic acid with olfactory ensheathing cells protect gentamicin-induced SGNs damage in the rat cochlea in vitro

Hearing is mainly dependent on the function of hair cells (HCs) and spiral ganglion neurons (SGNs) which damage or loss of them leads to irreversible hearing loss. Olfactory ensheathing cells (OECs) are specialized glia that forms the fascicles of the olfactory nerve by surrounding the olfactory sensory axons. The OECs, as a regenerating part of the nervous system, play a supporting function in axonal regeneration and express a wide range of growth factors. In addition, retinoic acid (RA) enhances the proliferation and differentiation of these cells into the nerve. In the present study, we co-cultured human OECs (hOECs) with cochlear SGNs in order to determine whether hOECs and RA co-treatment can protect the repair process in gentamycin-induced SGNs damage in vitro. For this purpose, cochlear cultures were prepared from P4 Wistar rats, which were randomly appointed to four groups: normal cultivated SGNs (Control), gentamicin-lesioned SGNs culture (Gent), gentamicin-lesioned SGNs culture treated with OECs (Gent + OECs) and gentamicin-lesioned SGNs culture co-treated with OECs and RA (Gent + OEC& RA). The expression of a specific protein in SGNs was examined using immunohistochemical and Western blotting technique. TUNEl staining was used to detect cell apoptosis. Here, we revealed that combined treatment of OECs and RA protect synapsin and Tuj-1 expression in the lesioned SGNs and attenuate cell apoptosis. These findings suggest that RA co-treatment can enhance efficiency of OECs in repair of SGNs damage induced by ototoxic drug.

Extracellular vesicles isolated from human olfactory ensheathing cells enhance the viability of neural progenitor cells

OBJECTIVE

Acquired neurological diseases such as severe traumatic brain or spinal cord injury (SCI) cause irreversible disability. Olfactory ensheathing cell (OEC) transplantation has been trialed as a promising SCI treatment. Extracellular vesicles (EVs), which regulate cell-cell interactions, have recently garnered extensive research interests and emerged as a non-cell-based therapy in neurological disorders, including in SCI animal models. However, there have been no reports of human OEC-EVs and their beneficial effects on neuron regeneration. Here, we investigated the effects of EVs isolated from human OEC on the viability of neuronal cells.

METHODS

EVs were isolated from primary human OECs (hOECs) by serial ultracentrifugation. The hOEC-EVs were characterized by transmission electron microscopy, western blotting, and nanoparticle tracking analyses. We conducted CCK8 and lactate dehydrogenase assays to assess the cell proliferation and cytotoxicity of neural progenitor cells (NPCs) exposed to hOEC-EVs. Tert-butyl hydroperoxide (t-BHP) was utilized to mimic oxidative stress-induced cytotoxicity in NPCs.

RESULTS

The modal diameter of hOEC-derived EVs was 113.2 nm. Expressions of EV markers such as CD9, CD63, and CD81 were detected by western blotting. hOEC-derived EVs enhanced the proliferation of NPCs and ameliorated cell cytotoxicity mediated by t-BHP.

DISCUSSION

Our findings reveal a role for hOEC-derived EVs in NPC proliferation and oxidative stress-induced neuronal toxicity model. These results may be useful for developing non-cell therapy OEC-EV-based treatment in acquired nervous system disease.