The role of olfactory ensheathing cells in the repair of nerve injury

Immune characteristics of olfactory ensheathing cells and repair of nerve injury

The process of nerve injury is accompanied by the change of inflammatory microenvironment, which is not conducive to axonal regeneration and hinders the repair of injured nerve. Therefore, looking for a way to improve the inflammatory attack and immune state around the injured nerve is beneficial to the progress of nerve injury repair. In recent years, cell transplantation strategy has played a foreground role in the repair of nerve injury. Olfactory ensheathing cells (OECs) are a special kind of glial cells, which have the characteristics of continuous renewal and survival, antigenic characteristics, variability and promoting the repair of nerve injury. OECs have been recognized in different injury models, including clinical trials, which has become a dominant cell in cell replacement therapy. An important feature of OECs lies in their anti-inflammatory and immunomodulatory functions. They are transplanted into the host to improve the catastrophic inflammatory microenvironment caused by injured nerves, thus promoting the repair and regeneration of injured nerves. The transplantation of OECs into the host can provide good groundwork and support for the repair and regeneration of nerve injury by regulating the activity and infiltration of immune cells, the secretion of inflammatory cytokines and phagocytosis. Therefore, this paper discusses the anti-inflammatory and immunomodulatory mechanisms of OECs transplantation in the repair of nerve injury and the functional role of OECs as an ideal substitute in the treatment of nerve injury.

Role and Mechanism of Olfactory Stem Cells in the Treatment of Olfactory Disorders

Olfactory dysfunction is one of the most prevalent diseases in otorhinolaryngology, particularly since the coronavirus 2019 (COVID-19) pandemic, with a potential impact on daily life. Several etiological factors can contribute to olfactory dysfunction owing to the complexity and specificity of the olfactory transmission pathway. However, current treatments for olfactory dysfunction are limited and their efficacy is unsatisfactory. Olfactory stem cells are multifunctional stem cells in the olfactory mucosa that comprise both horizontal and global basal stem cells (HBCs and GBCs, respectively). These cells can differentiate into various cell types in response to different stimuli with distinct characteristics. The aim of the study was to discuss the mechanisms and functions of stem cells and their application in the treatment of olfactory dysfunction.