Spinal cord injuries (SCI) are an incurable, life-changing traumatic event that causes mainly irreversible damage to the spinal cord. This damage results in several symptoms, such as loss of motor and sensory function, that lead to a dramatic decrease in quality of life. There are approximately 500,000 new spinal cord injuries that occur around the world every year.
The causes of these injuries vary from motor vehicle accidents to surgical complications. Developing new, effective therapies for this condition is necessary to improve patient outcomes. Stem cell therapy is a potentially effective treatment method for spinal cord injury patients.
A study, Stem Cell Therapy for Spinal Cord Injury: A Review of Recent Clinical Trials, reviewed clinical trials that took place from 2017 until March 31st, 2022. This study is an excellent reference to the strides stem cell therapy has made in the past few years.
Results of the Study
The researchers initially found 372 potential articles, but 213 did not meet the time inclusion criteria. Another 136 studies did not meet the inclusion criteria. 23 articles were assessed for eligibility, and another six studies were excluded for a variety of reasons. An additional search yielded one more study, so in total, 18 clinical trials were assessed in this study.
The researchers assessed all of the clinical trials based on a few different criteria. Studies used various sources of stem cells.
Bone-Marrow Derived Stem Cells
Bone-marrow-derived stem cells are harvested from bone marrow, and their immunosuppressive and neuroprotective attributes can be used to improve SCI patient outcomes. Six clinical trials used bone-marrow-derived stem cells. In total, 42 patients received this type of stem cell therapy. In four studies, the patients received the stem cells via the spinal cord. In one study, the stem cells were delivered intravenously, and in the final study, the stem cells were delivered both intravenously and intrathecally.
In the Honmou et al study, 13 patients with subacute phase SCIs were treated with bone marrow stem cells. Patients were given one dose intravenously between 84 and 150 million cells. The researchers then followed the patients for six months. Seven patients showed improvement in AIS classification and n functional activities according to the ISCSI-92 and SCIM III scales.
Vaquero et al had multiple studies where bone marrow stem cells were utilized. In 2017, 10 patients received bone-marrow stem cells in a phase II clinical trial. The patients were given four doses of 30 million cells and were followed for 12 months. Patient motor and sensory scores improved after the treatment.
In another Vaquero et al phase II clinical trial in 2018, 11 patients received stem cell therapy. These patients were given three doses of 100 million cells via intrathecal administration. The researchers then followed the patients for ten months. 27% of patients showed an improvement in AIS classification after the treatment.
Umbilical Cord Mesenchymal Stem Cells
Umbilical cord mesenchymal stem cells (UCMSCs) are harvested from the umbilical cord, which means they are an almost infinite source of stem cells. This type of stem cell has anti-inflammatory, anti-apoptotic, neurotrophic, and proangiogenic effects when administered. The researchers identified three clinical trials that used UCMSCs.
In Deng et al study, 20 patients with cervical injuries were given doses of 40 million cells combined with a collagen scaffold. The scaffold was seeded with the stem cells and then transplanted into the patients. A control group received conventional treatment. After 12 months, nine patients improved from an AIS score of A to B, and two improved from an AIS score of A to C. Patients also experienced improvements in ADL scores and bowel and bladder function.
In Yang et al, 41 patients were given four intrathecal injections of one million cells. The researchers followed the patient for 12 months. The patients did not experience any adverse effects from the treatment. Additionally, patients showed improvements in AIS and IAN-SCARFS scores, as well as a decrease in muscle spasticity.
Umbilical Cord Wharton-Jelly Mesenchymal Stem Cells
Wharton’s-jelly mesenchymal stem cells (WJ-MSCs) are obtained through harvesting the Wharton’s jelly in the umbilical cord, a substance that insulates blood vessels. These stem cells can promote neurogenesis and angiogenesis when transplanted. The study identified one study that used WJ-MSCs to treat spinal cord injuries.
In Albu et al, researchers used WJ-MSCs to treat ten patients with chronic SCI. Patients received WJ-MSCs via intrathecal delivery. The patients were then followed for six months. As compared to the placebo group, the stem cell group showed significant improvement in pinprick sensation.
There were other studies that the researchers covered in this study. Overall, the study confirmed that stem cell therapy shows great promise in treating SCI patients. The study stressed that more research needs to take place before stem cell therapy can become widely accepted for spinal cord injuries.
