Therapeutic Evidence of Human Mesenchymal Stem Cell Transplantation for Cerebral Palsy: A Meta-Analysis of Randomized Controlled Trials

A systematic review of cell therapy modalities and outcomes in cerebral palsy

Cerebral palsy is widely recognized as a condition that results in significant physical and cognitive disabilities. Interventions aim to improve the quality of life and reduce disability. Despite numerous treatments and significant advancements, cerebral palsy remains incurable due to its diverse origins. This review evaluated clinical trials, studies, and case reports on various cell therapy approaches for cerebral palsy. It assessed the clinical outcomes of applying different cell types, including mesenchymal stem cells, olfactory ensheathing cells, neural stem/progenitor cells, macrophages, and mononuclear cells derived from peripheral blood, cord blood, and bone marrow. In 60 studies involving 1474 CP patients, six major adverse events (0.41%) and 485 mild adverse events (32.9%) were reported. Favorable therapeutic effects were observed in 54 out of 60 cell therapy trials, indicating a promising potential for cell treatments in cerebral palsy. Intrathecal MSC and BM-MNC applications revealed therapeutic benefits, with MSC studies being generally safer than other cell therapies. However, MSC and BM-MNC trials have shown inconsistent results, with some demonstrating superior efficacy for certain outcomes. Cell dosage, transplantation route, and frequency of administration can affect the efficacy of these therapies. Our findings highlight the promise of cell therapies for improving cerebral palsy treatment and stress the need for ongoing research to refine treatment protocols and enhance safety. To establish conclusive evidence on the comparative effectiveness of various cell types in treating cerebral palsy, randomized, double-blind clinical trials are essential.

The Impact of Umbilical Cord Mesenchymal Stem Cells on Motor Function in Children with Cerebral Palsy: Results of a Real-world, Compassionate use Study

The aim of this study was to analyze the impact of human umbilical cord-derived MSCs (hUC-MSCs) on motor function in children with cerebral palsy (CP). The study enrolled 152 children with CP who received up to two courses of five hUC-MSCs injections. Children's motor functions were assessed with the Gross Motor Function Measure (GMFM), 6-Minute Walk Test (6-MWT), Timed Up and Go test (Up&Go test), and Lovett's test, and mental abilities were assessed with the Clinical Global Impression (CGI) scale. Data collected at visit 1 (baseline) and visit 5 (after four injections) were analyzed retrospectively. After four hUC-MSCs administrations, all evaluated parameters improved. The change in GMFM score, by a median of 1.9 points (IQR: 0.0-8.0), correlated with age. This change was observed in all GFMCS groups and was noticed in all assessed GMFM areas. A median increase of 75 m (IQR: 20.0-115.0) was noted on the 6-MWT, and this correlated with GMFM score change. Time on the Up&Go test was reduced by a median of 2 s (IQR: -3 to - 1) and the change correlated with age, GMFM score at baseline, and the difference observed on the 6-MWT. Results of Lovett's test indicated slight changes in muscle strength. According to the CGI, 75.5% (96/151) of children were seriously (level VI) or significantly ill (level V) at the 1st visit, with any improvement observed in 63.6% (96/151) of patients at the 5th visit, 23.8% (36/151) with improvement (level II) or great improvement (level I). In conclusion, the application of hUC-MSCs generally enhanced functional performance, but individual responses varied. The therapy also benefited children with high level of disability but not to the same extent as the initially less disabled children. Although younger patients responded better to the treatment, older children can also benefit. Trial Registration 152/2018/KB/VII and 119/2021/KB/VIII. Retrospective registration in ClinicalTrials: ongoing.

Efficacy and safety of stem cell therapy in cerebral palsy: A systematic review and meta-analysis

Aim: Although the efficacy and safety of stem cell therapy for cerebral palsy has been demonstrated in previous studies, the number of studies is limited and the treatment protocols of these studies lack consistency. Therefore, we included all relevant studies to date to explore factors that might influence the effectiveness of treatment based on the determination of safety and efficacy. Methods: The data source includes PubMed/Medline, Web of Science, EMBASE, Cochrane Library, from inception to 2 January 2022. Literature was screened according to the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the outcome indicators of each study were extracted for combined analysis. Results: 9 studies were included in the current analysis. The results of the pooled analysis showed that the improvements in both primary and secondary indicators except for Bayley Scales of Infant and Toddler Development were more skewed towards stem cell therapy than the control group. In the subgroup analysis, the results showed that stem cell therapy significantly increased Gross Motor Function Measure (GMFM) scores of 3, 6, and 12 months. Besides, improvements in GMFM scores were more skewed toward umbilical cord mesenchymal stem cells, low dose, and intrathecal injection. Importantly, there was no significant difference in the adverse events (RR = 1.13; 95% CI = [0.90, 1.42]) between the stem cell group and the control group. Conclusion: The results suggested that stem cell therapy for cerebral palsy was safe and effective. Although the subgroup analysis results presented guiding significance in the selection of clinical protocols for stem cell therapy, high-quality RCTs validations are still needed.

Stem cell-based therapy for human diseases

Recent advancements in stem cell technology open a new door for patients suffering from diseases and disorders that have yet to be treated. Stem cell-based therapy, including human pluripotent stem cells (hPSCs) and multipotent mesenchymal stem cells (MSCs), has recently emerged as a key player in regenerative medicine. hPSCs are defined as self-renewable cell types conferring the ability to differentiate into various cellular phenotypes of the human body, including three germ layers. MSCs are multipotent progenitor cells possessing self-renewal ability (limited in vitro) and differentiation potential into mesenchymal lineages, according to the International Society for Cell and Gene Therapy (ISCT). This review provides an update on recent clinical applications using either hPSCs or MSCs derived from bone marrow (BM), adipose tissue (AT), or the umbilical cord (UC) for the treatment of human diseases, including neurological disorders, pulmonary dysfunctions, metabolic/endocrine-related diseases, reproductive disorders, skin burns, and cardiovascular conditions. Moreover, we discuss our own clinical trial experiences on targeted therapies using MSCs in a clinical setting, and we propose and discuss the MSC tissue origin concept and how MSC origin may contribute to the role of MSCs in downstream applications, with the ultimate objective of facilitating translational research in regenerative medicine into clinical applications. The mechanisms discussed here support the proposed hypothesis that BM-MSCs are potentially good candidates for brain and spinal cord injury treatment, AT-MSCs are potentially good candidates for reproductive disorder treatment and skin regeneration, and UC-MSCs are potentially good candidates for pulmonary disease and acute respiratory distress syndrome treatment.

Stem Cell Transplantation Therapy and Neurological Disorders: Current Status and Future Perspectives

Neurodegenerative diseases are a global health issue with inadequate therapeutic options and an inability to restore the damaged nervous system. With advances in technology, health scientists continue to identify new approaches to the treatment of neurodegenerative diseases. Lost or injured neurons and glial cells can lead to the development of several neurological diseases, including Parkinson's disease, stroke, and multiple sclerosis. In recent years, neurons and glial cells have successfully been generated from stem cells in the laboratory utilizing cell culture technologies, fueling efforts to develop stem cell-based transplantation therapies for human patients. When a stem cell divides, each new cell has the potential to either remain a stem cell or differentiate into a germ cell with specialized characteristics, such as muscle cells, red blood cells, or brain cells. Although several obstacles remain before stem cells can be used for clinical applications, including some potential disadvantages that must be overcome, this cellular development represents a potential pathway through which patients may eventually achieve the ability to live more normal lives. In this review, we summarize the stem cell-based therapies that have been explored for various neurological disorders, discuss the potential advantages and drawbacks of these therapies, and examine future directions for this field.

Human pluripotent stem cell-derived ectomesenchymal stromal cells promote more robust functional recovery than umbilical cord-derived mesenchymal stromal cells after hypoxic-ischaemic brain damage

Aims: Hypoxic-ischaemic encephalopathy (HIE) is one of the most serious complications in neonates and infants. Mesenchymal stromal cell (MSC)-based therapy is emerging as a promising treatment avenue for HIE. However, despite its enormous potential, the clinical application of MSCs is limited by cell heterogeneity, low isolation efficiency and unpredictable effectiveness. In this study, we examined the therapeutic effects and underlying mechanisms of human pluripotent stem cell-derived ectomesenchymal stromal cells (hPSC-EMSCs) in a rat model of HIE.

Methods: hPSC-EMSCs were induced from either human embryonic stem cells or induced pluripotent stem cells. Stem cells or the conditioned medium (CM) derived from stem cells were delivered intracranially or intranasally to neonatal rats with HIE. Human umbilical cord-derived MSCs (hUC-MSCs) were used as the therapeutic comparison control and phosphate-buffered saline (PBS) was used as a negative control. Lesion size, apoptosis, neurogenesis, astrogliosis and microgliosis were evaluated. The rotarod test and Morris water maze were used to determine brain functional recovery. The PC-12 cell line, rat primary cortical neurons and neural progenitor cells were used to evaluate neurite outgrowth and the neuroprotective and neurogenesis effects of hPSC-EMSCs/hUC-MSCs. RNA-seq and enzyme-linked immunosorbent assays were used to determine the secretory factors that were differentially expressed between hPSC-EMSCs and hUC-MSCs. The activation and suppression of extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) were characterised using western blotting and immunofluorescent staining.

Results: hPSC-EMSCs showed a higher neuroprotective potential than hUC-MSCs, as demonstrated by a more significant reduction in lesion size and apoptosis in the rat brain following hypoxia-ischaemia (HI). Compared with PBS treatment, hPSC-EMSCs promoted endogenous neurogenesis and alleviated astrogliosis and microgliosis. hPSC-EMSCs were more effective than hUC-MSCs. hPSC-EMSCs achieved a greater recovery of brain function than hUC-MSCs and PBS in rats with HIE. CM derived from hPSC-EMSCs had neuroprotective and neurorestorative effects in vitro through anti-apoptotic and neurite outgrowth- and neurogenesis-promoting effects. Direct comparisons between hPSC-EMSCs and hUC-MSCs revealed the significant enrichment of a group of secretory factors in hPSC-EMSCs, including nerve growth factor (NGF), platelet-derived growth factor-AA and transforming growth factor-β₂, which are involved in neurogenesis, synaptic transmission and neurotransmitter transport, respectively. Mechanistically, the CM derived from hPSC-EMSCs was found to potentiate NGF-induced neurite outgrowth and the neuronal differentiation of NPCs via the ERK/CREB pathway. Suppression of ERK or CREB abolished CM-potentiated neuritogenesis and neuronal differentiation. Finally, intranasal delivery of the CM derived from hPSC-EMSCs significantly reduced brain lesion size, promoted endogenous neurogenesis, mitigated inflammatory responses and improved functional recovery in rats with HIE.

Conclusion: hPSC-EMSCs promote functional recovery after HI through multifaceted neuromodulatory activities via paracrine/trophic mechanisms. We propose the use of hPSC-EMSCs for the treatment of HIE, as they offer an excellent unlimited cellular source of MSCs.

Clinical Efficacy and Safety of Human Mesenchymal Stem Cell Therapy for Degenerative Disc Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Degenerative disc disease (DDD) can cause severe low back pain, which will have a serious negative impact on the ability to perform daily tasks or activities. For the past few years, mesenchymal stem cell (MSC) transplantation has emerged as a promising strategy for the treatment of DDD. However, the clinical efficacy of MSC in the treatment of DDD still lacks clinical evidence and is controversial. We conducted a meta-analysis with randomized controlled trials (RCTs) to evaluate the clinical efficacy and safety of MSC transplantation in patients with DDD. We searched major databases using terms from the database's inception through March 2021. The Cochrane bias risk assessment tool was used to assess quality. The analysis showed that MSC therapy could decrease visual analog scale (VAS) scores (SMD = −0.50, 95%CI = −0.68 ~ −0.33, P < 0.00001) and Oswestry Disability Index (ODI) scores (SMD = −0.27, 95%CI = −0.44 ~ −0.09, P = 0.003). The outcomes with subgroup analysis showed that MSC therapy could decrease VAS scores in 3 months (P = 0.001), 6 months (P = 0.01), 12 months (P = 0.02), and ≥24 months (P = 0.002) and ODI scores in ≥24 months (P = 0.006). Pooled analysis showed that MSC therapy has a higher ratio of patients at most thresholds but particularly at the MIC (minimally important change) (P = 0.0002) and CSC (clinically significant change) (P = 0.0002) in VAS and MIC (P = 0.0005) and CSC (P = 0.001) pain responders in ODI. Adverse events (AE) of treatment-emergent adverse events (TEAE), back pain, arthralgia, and muscle spasms were not statistically significant between the two groups. However, our further statistical analysis showed that MSC therapy may induce AE of TEAE related to study treatment (OR = 3.05, 95%CI = 1.11 ~ 8.40, P = 0.03). In conclusion, this study pooled the main outcomes and showed that MSC therapy could significantly decrease VAS and ODI scores in patients with DDD. Distinctly, the findings of this meta-analysis suggest a novel therapeutic strategy for patients with chronic low back pain (LBP) and lumbar dysfunction by DDD.