Stem cells and stem cell therapy are on the cutting edge of modern medicine, science and technology. A stem cell line is a group of cells that all descend from a single original stem cell and is grown in a lab. Cells in a stem cell line keep growing but do not differentiate into specialized cells. Ideally, they remain free of genetic defects and continue to create more stem cells. Clusters of cells can be taken from a stem cell line and frozen for storage or shared by researchers. Stem cell therapy, also known as regenerative medicine, promotes the reparative response of diseased, dysfunctional or injured tissue using stem cells or their derivatives (Mayo Clinic).
Researchers grow stem cells in a lab for their specific therapeutic focus. These stem cells are manipulated to specialize into specific types of cells, such as heart muscle cells, blood cells or nerve cells, and can also be used to deliver substances for a specific function. We are focusing on stem cell therapy in TBI in this interview with Dr. Jerry Liu.
There are some promising open label trails for stem cell therapy in stroke - how have those progressed, and how does this relate to traumatic brain injury treatment?
Clinical trials have reported an acceptable safety profile with some functional benefits to patients with stroke using transplanted neuronal cells differentiated from various stem cell sources. These stem cell sources include teratocarcinoma cell line, human immature neural and hematopoietic cells, autologous human bone marrow–derived mononuclear cells, and mesenchymal stem cells. The administration of the cells in these studies includes intracerebral, intra-arterial, intravenous, or intracerebroventricular routes during the period of days to years after a stroke.
What are the risks associated with stem cell therapy?
Like any new drug development, stem cell therapy needs to be carefully tested for its efficacy and safety. Depending on the strategy of the cell therapy, and its mechanism of action, safety issues can include but are not limited to the following: engrafted cells sensitize the patient’s immune system and cause failure of engraftment or no function of transplanted cells; cells may carry pathogens acquired from either the donor or the production process; engrafted cells undergo mutation and become tumorigenic or cause malformations; or procedure-related side effects (e.g., infection) may occur.
From preclinical and clinical data, we know that SB623 cells will not engraft (continue to grow and integrate) in the host, and that they disappear after a short period of time (a few weeks to a month). So SB623 cells can be seen as a delivery system of a wealth of growth factors, along with stimulation of endogenous pro-growth and pro-differentiation mechanisms within the patient. This characteristic provides a safety benefit by avoiding immune –related risks and tumorigenic risks.
Various interventions target different symptoms. What are the most likely benefits to recovery and functioning from stem cell therapy after brain injury?
According to literature and anecdotal reports, stem cell implantation was observed to be associated with various functional improvements, particularly motor function and memory (Kondziolka 2005, Lancet, and Steinberg 2016 Stroke).
How is this work being advanced, and what is the role of the brain injury community in moving the research forward?
Currently, a clinical trial in TBI patients with chronic motor deficits sponsored by SanBio is enrolling in both the USA and Japan. There approximately 25 sites in the US and 5 sites in Japan. Given the investigational nature of this study, a set of criteria have been put in place to enroll patients with proper baseline symptoms into the study. The brain injury community can help to pass the word to enhance the awareness of study in patients with TBI.
For more information on brain injury stem cell therapy clinical trials please contact Mirella Machuca - mirella.machuca@sanbio.com.
About the Interviewer
Tina M. Trudel, PhD, CBIST is the Chief Executive Officer and Clinical Neuropsychologist for Northeast Evaluation Specialists, providing assessment and rehabilitation at locations throughout New England. She is a NABIS Board member, author of over 50 brain injury publications, and co-editor of the recent Essential Brain Injury Guide 5.0.
About the Expert
W. Jerry Liu, MD, currently works as the Head of Clinical Development, North Amer-ica, of Sanbio, INC, a Bay area biotech firm dedicated to cell therapy and regenera-tive medicine for the treatment of neurological disorders. Prior to this position, Dr. Liu was with Ipsen, as a Senior Global Medical Development Director. He has 15 years of working experience in drug R&D and completed his medical degree from Peking University, and residency training in Surgery in Peking Medical College University Hospital in Beijing.
Trudel, T. M., & Liu, W. (2016). Technology and TBI Column highlights - cutting edge research in stem cell therapy. Brain Injury Professional, 13(3), 28.
From Brain Injury Professional, an official publication of the International Brain Injury Association and the North American Brain Injury Society. www.braininjuryprofessional.com Reprinted with permission.