Olfactory ensheathing glia and Schwann cells exhibit a distinct interaction behavior with meningeal cells

Schwann cells (SCs) and olfactory ensheathing glia (OEG) have both been used as cellular transplants to promote spinal cord repair. Both cell types support axonal regeneration and have beneficial effects on functional recovery. A significant difference between SCs and OEG is the effect of these cell types on astrocytes (ACs) present in the neural scar. In contrast to OEG, which associate and intermingle with ACs, SCs and ACs form separate cellular territories. Here, we show that OEG and SCs also interact differently with meningeal cells (MCs), another major cellular component of the neural scar. Whereas OEG intermingle with MCs in cocultures, SCs aggregate into well-defined cell clusters. Our data suggest that (a) soluble factor(s) as well as direct cellular contact are involved in the MC-induced SC clustering. Furthermore, the cluster formation of SCs in coculture with MCs is different from the previously reported segregation of SCs and ACs in coculture. The present results help to understand the differential behavior of both cell types after transplantation in the injured spinal cord and will be important to either determine which cell has optimal capacities to render the scar more permissive for regeneration, or to exploit the transplantation of both cell types in combination.