2022, Vol. 26 ›› Issue (25): 4093-4100

Efficacy and safety of human umbilical cord mesenchymal stem cells in the treatment of spinal cord injury: a meta-analysis

Shi Yao1, Han Shufeng2, Yuan Yitong3, Du Ruochen3, Jing Zhijie3, Zhao Bichun3, Zhang Ruxin3, Zhang Yujuan3, Wang Chunfang3   

Abstract: OBJECTIVE: There is still a lack of effective treatments for spinal cord injury. Cell therapy could be a promising treatment method, in which human umbilical cord mesenchymal stem cells have received wide attention, because of its easy availability, low cost, less ethical issues, and low immunogenicity. At present, it has not been widely used in clinical practice, and its effectiveness and safety are still controversial. A meta-analysis was used to evaluate the efficacy and safety of human umbilical cord mesenchymal stem cells in the treatment of spinal cord injury.
METHODS: We searched English databases (PubMed, Web of Science, Cochrane, and EMbase) and Chinese databases (CNKI, Wanfang Medical Network, and VIP), and collected clinical articles on human umbilical cord mesenchymal stem cells in the treatment of spinal cord injury. The retrieval period was from the establishment of the database to April 2021. Two investigators independently read the included studies, extracted the data, and assessed the quality. The randomized controlled trials were scored using the modified Jadad scoring scale, and the Cochrane risk bias assessment tool was used to assess the risk of bias. The cohort studies were evaluated using the NOS scale. Meta-analysis was performed using RevMan5.3 software.
RESULTS: A total of 10 studies involving 370 patients, containing 6 randomized controlled trials and 4 cohort studies, were included. The overall quality of the studies was high. Results of the meta-analysis showed that (1) the ASIA sensory function score (MD=5.20, 95%CI:3.50-6.90, P < 0.000 01), the improvement rate of AIS grading (RR=2.26, 95%CI:1.40-3.65, P=0.000 8), and the Barthel index (MD=5.12, 95%CI:1.04-9.20, P=0.01) were higher in the human umbilical cord mesenchymal stem cell treatment group than those in the control group. (2) Compared with the control group, there was no significant difference in ASIA motor function score (MD=3.48, 95%CI:-0.14-7.10, P=0.06), ASIA pinprick sensation score (MD=7.58, 95%CI:-0.44-15.59, P=0.06) and ASIA light touch score (MD=7.67, 95%CI:-0.42-15.77, P=0.06) in the human umbilical cord mesenchymal stem cell treatment group. (3) Sensitivity analysis showed that the ASIA motor function score was higher in the human umbilical cord mesenchymal stem cell treatment group than that in the control group (MD=6.14, 95%CI:4.46-7.81, P < 0.000 01), and the results remained consistent with the previous one for the activities of daily living. In the 10 included articles, no serious adverse reactions were reported, but minor adverse reactions did exist and disappeared after symptomatic treatment.
CONCLUSION: The available clinical evidence shows that human umbilical cord mesenchymal stem cells are safe and effective in the treatment of spinal cord injury, with significant improvement in patients’ sensory and motor functions as well as their activity of daily living.
Key words: spinal cord injury, stem cell therapy, mesenchymal stem cells, human umbilical cord mesenchymal stem cells, ASIA score, AIS classification, activity of daily living scale, meta-analysis