Currently there is no form of therapy to cure autism. Modern treatments and therapies for autism include medical (treatment of anxiety and depression), nutritional (restriction of allergy-associated dietary components / supplementation of minerals and vitamins / antioxidant therapy) and behavioural. None are curative. Research has been slow and interested in the neurophysiology between the immune system and the nervous system.
The rationale for stem cells treatment for autism lies in the administration of CD34+ umbilical cord cells and mesenchymal cells. It is theorised that these cells may help the hypoperfusion of the brain and immune malfunction. Treatment with these stem cells together may potentially improve both the brain and the gut in these patients with autism. Anecdotal results from the treatment of autistic children in some clinics are very encouraging.
The use of umbilical cord blood CD34+ stem cells in autism is due to the fact that these cells have a role to play in angiogenesis. This is the formation of new and collateral blood vessels and is necessary for brain recovery. It is this fact that makes CD34+ Haemopoietic stem cells so useful in the treatment of neurodegenerative diseases. The infusion of CD34+ vascular progenitor stem cells from umbilical cord blood may lead to new vessel formation. Consequently improved blood flow and oxygen to the brain should improve nervous system functioning and this should theoretically improve autistic patients. Safety concerns regarding allogeneic (another individuals) CD34+ cells; in particular fears of graft versus host reactions have not been borne out. Riordan et al (6) have recently published an account of the safety and feasibility of cord blood cells administration in absence of immune suppression, i.e. without the need for suppressing an individual’s immune response. There are numerous reports of stem cell treatments where no immune suppression was used; one study followed up 500 patients without a single one suffering graft vs. host reaction.
Mesenchymal stem cells alter the immune system in the brain. Research data suggests that this will influence neurological function profoundly. The ability of mesenchymal stem cells to suppress pathological immune responses (e.g. inflammation) and to stimulate haematopoiesis and angiogenesis (blood cell regeneration) suggests that these mesenchymal stem cells may be useful for treatment of the defect in T cell numbers associated with autism. This is another area of active research within our group.
It is believed that the use of combination therapy utilising CD34+ stem cells and mesenchymal stem cells may induce synergistic effects in the treatment of neurological diseases. We propose to treat autistic patients with both these types of stem cells, as our experience suggests that treatment with only one type of stem cell is not clinically efficacious.
While the rationale for using stem cells to treat autism is sound and many anecdotal cases suggest significant improvement, almost all proponents of stem cell treatment for autism are in agreement that more clinical trials are needed to assess treatment efficacy. When patients and their families consider new treatments, the proposals need to be interpreted in a discerning manner that can be balanced with scientific evidence. Patients considering this therapy should ensure that they consult fully with their own doctor and specialist to make sure that they are getting optimal treatment with the appropriate combination of CD34+ stem cells and mesenchymal stem cells.
Autism is a neurological developmental disorder, characterised by a number of abnormalities that includes poor social interactions, communication difficulties, obsessive attachment to routines and repetition, and often an extreme dislike of certain sounds, textures and tastes. Autism usually presents within the first three years of life and is of variable severity ranging from the very mild (Asperger’s type) to chronically disabling. Evidence suggests that are two abnormalities in the brain that are seen in autism. The causes of autism are thought to be due to environmental, immunological and neurological factors. There are no specific MRI or other radiological findings.
Autism afflicts roughly 1 in 200 of the general population and this condition is also being reported as one of the fastest-growing developmental disabilities in the US, although with the advent of stem cell based interventions and treatments there may be ‘light at the end of the tunnel’. This diagnosis has reached staggering proportions in the last decade with an estimated 1.5 million children and adults in the U.S. currently (as at 2007) having some form of autism. Autism spectrum disorders such as Asperger’s Syndrome are believed to affect approximately 1 in 166 children.
The two main abnormalities which have been recognised are firstly, due to decreased perfusion in the brain and secondly, due to immune abnormalities. The decreased cerebral perfusion may cause abnormal function in the brain from hypoxia (reduced oxygen supply) and by decreased cell membrane function, causing the build up of abnormal substances (metabolites or neurotransmitters).
It is thought that if perfusion can be improved through the growth of new blood vessels (angiogenesis), then this should also allow better perfusion as well as enhanced metabolite clearance and restoration of brain function.
In addition there is an abnormality of the immune system seen in autism. In autism, it is thought that an autoimmune response against the brain’s own self causes part of the loss of functioning. Astrocytes (supportive brain cells) that usually play a vital role in regulating perfusion and protection against central nervous system infection, may have the potential to affect neurodevelopment when functioning in a self destructive way. Other putative evidence for this is that autistic patients often demonstrate chronic inflammation amongst other organs, such as the stomach as well as the central nervous system.
1. Review: Stem Cell Therapy for Autism Thomas Ichim, Fabio Solano, Eduardo Glenn, Frank Morales, Leonard Smith, George Zabrecky, Neil H Riordan Journal of Translational Medicine June 2007, 5:30 http://www.translational-medicine.com/content/5/1/30
2. Alliance for stem cell research http://www.curesforcalifornia.com
3. The immune response in autism: a new frontier for autism research Paul Ashwood, Sharifia Wills, Judy vd Water Journal of Leukocyte Biology. 80:1–15; 2006
4. The Stem Cell and Autism Connection http://www.bodyecology.com
5. Autism http://www.stemcelltherapies.org
6. Cord blood in regenerative medicine: do we need immune suppression? Riordan N, Chan K, Marleau A, Ichim T. Journal of Translational Medicine. Jan 2007 5:8
7. http://www.autismvox.com/another-autism-treatment-stem-cell-therapy Kristina Chew, July 2007
8. http://www.cellmedicine.com (publication is equivalent to Review: Stem Cell Therapy for Autism Ichim et al.)
9. Osiris http://www.osiris.comhttp://www.translational-medicine.com/content/5/1/30
