Is cell transplantation a reliable therapeutic strategy for spinal cord injury in clinical practice? A systematic review and meta-analysis from 22 clinical controlled trials.

Purpose: It is an open question whether cell transplantation can provide safety and effective outcome to spinal cord injury (SCI) patient which has remained controversial for almost 40 years. This study aimed to evaluate the safety and efficacy of cell transplantation in SCI patients.

Method: Studies of the cell transplantation for SCI were retrieved from PubMed, Embase, Medline, Cochrane Library and analyzed quantitative data by Review Manager 5.3.

Results: Twenty-one clinical controlled studies with 973 patients were included. The pooled results suggested that cell transplantation significantly improved ASIA score, ASIA motor score, ASIA sensory score, Barthel Index score, residual urine volume, rehabilitative time of automatic micturition. Furthermore, subgroup analysis indicated that the stem cells exhibited more potent than the non-stem cells in spinal cord repair. Cell transplantation at more than 14 days after injury showed more significant improvements than that within 14 days from injury. The dosage of cell transplantation between 1-5 × 10 and 10-20 × 10 was the potent quantity for the patient with SCI. Intrathecal injection and intravenous + intrathecal injection showed more superior to the other method. The top 5 adverse events were febrile reaction (11.5%), neurologic pain (11.3%), headache (2.6%), neurologic deterioration (2.4%), and rigidity or spasticity (1.6%).

Conclusion: Cell transplantation appears to be a safe therapeutic strategy possessing substantial beneficial effects in the patients with SCI in clinic. Moreover, treating SCI with stem cell, the dosage of cells between 1-5 × 10 and 10-20 × 10, in intermediate or chronic phase, minimally invasive techniques, may bring more advantage to SCI patient. These slides can be retrieved under Electronic Supplementary Material.