Nav: Home

Improving cell transplantation after spinal cord injury: When, where and how?

May 31, 2016

Spinal cord injuries are mostly caused by trauma, often incurred in road traffic or sporting incidents, often with devastating and irreversible consequences, and unfortunately having a relatively high prevalence (250,000 patients in the USA; 80% of cases are male). One currently explored approach to restoring function after spinal cord injury is the transplantation of olfactory ensheathing cells (OECs) into the damaged area. The hope is that these will encourage the repair of damaged neurons, but does it work? And if so, how can it be optimized?

According to a systematic analysis of the literature published this week in PLOS Biology, after experimental spinal cord injury, transplanting OECs into the site of damage does indeed significantly improve locomotor performance. To reach this conclusion, Ralf Watzlawick, Jan Schwab, and their colleagues at the Ohio State University Wexner Medical Center, Charité Universtaetsmedizin Berlin and the CAMARADES consortium (Collaborative Approach to Meta Analysis and Review of Animal Data from Experimental Studies), analyzed 49 studies, published between 1949 and 2014, which included 62 experiments involving 1164 animals.

Restoration of function after spinal cord injury remains one of the most formidable challenges in regenerative medicine, but cell transplantation into the spinal cord represents a promising treatment strategy. OECs are considered particularly suitable for transplantation because they have been shown to be neuro-protective and to promote neuro-regeneration in different settings, and can be extracted from the patient's own nasal cavity, thereby minimizing the chances of graft rejection and avoiding the need for immunosuppressive drugs.

However, reports in the literature about the efficacy of transplantation of OECs for treatment of spinal cord injury have been contradictory. Therefore, to investigate the in vivo evidence for the efficacy of this procedure, the authors implemented a systematic review and meta-analysis of the literature. Importantly, the authors set out to explore the potential influence of variations in experimental approaches and unreported data.

"We felt that after more than two decades since the discovery that OECs elicit effects on neural plasticity in vivo, it was time to test their effects by appropriate methodology beyond reproduction", the authors argued.

The data analysed by the authors justify the use of OECs as a cellular substrate to develop and to optimize minimally invasive and secure protocols for repairing damaged spinal cord. They also identified several aspects of the cell transplantation procedure that could have a significant impact on the size of the therapeutic effect, including: the time-point of application, the use of surgical micro-dissection to "refresh" the scar tissue, the localization of transplanted cells, the number of injections, the injected volume, and the dose of cells administered.

Importantly, by using state-of-the-art statistical methods the authors also found that the impact of publication bias (due to selective failure to report results) was minimal, further supporting the translational potential of this approach.

Despite being focussing on OECs, the findings may be of more general relevance for optimizing the transplantation of other cell types after spinal cord injury.
-end-
Additional information:

The Collaborative Approach to Meta Analysis and Review of Animal Data from Experimental Studies.

http://www.dcn.ed.ac.uk/camarades/

In your coverage please use this URL to provide access to the freely available article in PLOS Biology: http://dx.plos.org/10.1371/journal.pbio.1002468

Citation: Watzlawick R, Rind J, Sena ES, Brommer B, Zhang T, Kopp MA, et al. (2016) Olfactory Ensheathing Cell Transplantation in Experimental Spinal Cord Injury: Effect size and Reporting Bias of 62 Experimental Treatments: A Systematic Review and Meta-Analysis. PLoS Biol 14(5): e1002468. doi:10.1371/journal.pbio.1002468

Funding: RW was sponsored by the "Studienstiftung des deutschen Volkes" (#186392). JMS received funding support from the Else-Kroehner-Fresenius Foundation, the Wings-for-Life Spinal Cord Research Foundation (#60-2012), and the W.E. Hunt & C.M. Curtis Endowment. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

PLOS

Related Spinal Cord Injury Articles:

From spinal cord injury to recovery
Spinal cord injury disconnects communication between the brain and the spinal cord, disrupting control over part of the body.
Transplanting adult spinal cord tissues: A new strategy of repair spinal cord injury
Spinal cord injury repair is one of the most challenging medical problems, and no effective therapeutic methods has been developed.
Timing could mean everything after spinal cord injury
Moderate damage to the thoracic spinal cord causes widespread disruption to the timing of the body's daily activities, according to a study of male and female rats published in eNeuro.
New approach could jumpstart breathing after spinal cord injury
A research team at the Krembil Research Institute in Toronto has developed an innovative strategy that could help to restore breathing following traumatic spinal cord injury.
Gene signature predicts outcome after spinal cord injury
Scientists have determined a gene signature that is linked to the severity of spinal cord injury in animals and humans, according to a study in the open-access journal eLife.
More Spinal Cord Injury News and Spinal Cord Injury Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...