Stem Cell Stroke Study Surprise Findings

The treatment and success rate of stroke rehab and recovery varies greatly by person, and it can often be a lifelong process. Various types of stem cells are currently being studied as a potential therapy with the intent to aid the recovery of stroke victims, helping protect the brain by suppressing inflammation, boosting its ability to repair damage, regain function, and improve quality of life.1

Small Study, Surprising Outcome

One such study, recently published in the medical journal Stroke, has garnered a lot of media attention because of its unexpected findings. Researchers caution it is too early to tell from this small safety study if this is a breakthrough in potential treatment for stroke survivors but it does point to the need for further investigation. Led by Stanford University, the small study involved just 18 patients (16 included in the clinical analysis) and was designed to evaluate the safety of injecting stem cells from bone marrow directly into the areas of the brain damaged by stroke,2 but after the treatment, patients in the study had apparent improvement in their symptoms.

The patients enrolled in the study had substantial loss of movement and motor impairment, such as not being able to walk or move their arms or legs. Some had had a stroke as long as three to five years before the experimental treatment. Through a small hole drilled in their skulls, each patient was injected with stem cells from the bone marrow of adult donors. Patients were then tested after one month, six months, and twelve months with brain imaging and several standard scales that look at speech, vision, motor ability, and other aspects of daily functioning. Patients had minimal adverse effects (mostly headache, nausea, and vomiting) from the surgery, helping provide evidence of the safety of the procedure itself, but the unexpected finding? The study population’s mean scores on several of the standard scales improved within a month and continued to improve for several months afterward, maintaining these improvements at six and twelve months post-surgery. Symptom improvement included some patients being able to lift their arms over their heads, improvement in the ability to stand, and the disappearance of tremors.

More Research on the Horizon

Scientists are not exactly sure why this happened, and they need to do further research to figure out if these bone marrow stem cells helped symptoms to improve and if the findings would be similar in a larger control group study. An expanded, randomized, blinded trial is now underway that aims to enroll 156 chronic stroke patients to either undergo the same promising procedure or be part of a placebo control group. The study results are expected in about two years. Pretty exciting.


  1. Jessica M. Sun, Joanne Kurtzberg. Cord blood for brain injury. Cytotherapy. 2015; 17(6): 775-785.
  2. Gary K. Steinberg, Douglas Kondziolka, Lawrence R. Weschler, et al. Clinical Outcomes of Transplanted Modified Bone Marrow–Derived Mesenchymal Stem Cells in Stroke: A Phase 1/2a Study. Stroke. 2016; 47(7): 1817-1824.
Gina Satta

Posted by

Gina Satta is a writer, namer and new mom living in San Francisco. When she isn’t brainstorming brilliant copy, she is either looking for parking, making up new versions of classic nursery rhymes, or eating chocolate. Gina is a paid consultant to CBR.

Leave a Reply

Your email address will not be published. Required fields are marked *