Xenografts of expanded primate olfactory ensheathing glia support transient behavioral recovery that is independent of serotonergic or corticospinal axonal regeneration in nude rats following spinal cord transection

A Systematic Review of Cellular Transplantation Therapies for Spinal Cord Injury

“…This is only one of many studies in which the claims of robust axonal regeneration after OEC transplantation were not confirmed, and possible differences in the types of OECs utilized may be one of many potential explanations. For example, a similar study to that of Ramon-Cueto and colleagues (2000), but using primate OECs implanted into nude rats, failed to reveal any CST regeneration but a modest regeneration of 5-HT fibers (Guest et al, 2008).…”

“…The reasons for these discrepancies are not fully understood, although experimental bias, variability of the cell sources and culture conditions, and animal or injury model systems are all likely contributing factors. Importantly, about two thirds (13 of 18) of the studies reported improved behavioral outcomes, yet increased autotomy was seen in some studies (Guest et al, 2008;Richter et al, 2005), which raises the question of neuropathic pain and cautions against the indiscriminative application of OECs. Further studies with human OECs are clearly warranted, but these will require a better understanding of OEC biology with which to strengthen the rationale for human translation.…”

The Migration of Olfactory Ensheathing Cells during Development and Regeneration

“…‘Central OECs’ used for transplantation therapies are often acquired from the entire NFL of the olfactory bulb, which may, or may not, include OECs from both the inner and outer NFLs [90,91,92]. However, other studies have used central OECs without specifying the topographical locations from which they were obtained [93] or have used a more restricted population of central OECs such as the rostral region of the olfactory bulb [94] or the ventral olfactory bulb [95]. ‘Peripheral OECs’ from the lamina propria underlying the olfactory epithelium lining the nasal cavity have also been used [77], particularly as they have relevance to human trials due to their accessibility within the nasal cavity [73,74,75,78,96].…”

Comparison of bulbar and mucosal olfactory ensheathing cells using FACS and simultaneous antigenic bivariate cell cycle analysis

“…Examples include: (a) the source of the tissue: olfactory bulb (OB), (Li et al, 1997;Ram on-Cueto et al, 1998), olfactory mucosa or lamina propria (LP); (Au and Roskams, 2002;F eron et al, 1999), (b) the age of the donor [adult, neonatal, or fetal; (Barnett and Roskams, 2008;Huang et al, 2008)], (c) the time in tissue culture (Garcia-Escudero et al, 2010a;Llamusi et al, 2010;Novikova et al, 2010), (d) whether the OECs are purified [in most studies, e.g., (Barnett and Chang, 2004;Chuah and Au, 1993)], or used as mixed primary cultures (Deumens et al, 2006;Raisman and Li, 2007;Yui et al, 2011), or cell lines (Garcia-Escudero et al, 2010b), (e) the use of growth factors (Bianco et al, 2004;Pollock et al, 1999), (f) the species: apart from the rat, other OECs have been prepared from mouse , pig (Radtke et al, 2004), dog (Ito et al, 2006), monkey (Guest et al, 2008), and human (Barnett et al, 2000;F eron et al, 1998).…”