The article below is from the most recent issue of the AKC Delegates publication PERSPECTIVES. It is reprinted here with their permission for your information.

Dyane Baldwin
ACC AKC Delegate


STEM CELL THERAPY IN DOGS:
CURING THE INCURABLE?

RICHARD VULLIET, PH.D., DVM, Laboratory of Veterinary Cytotherapeutics, U.c. Davis Arranged by Pamela Stacy Rosman, Canaan Dog Club of America Invited by Crecia Closson, Lakes Region Kennel Club Reprinted with permission from Perspectives June 2008

HEALTH

We are all aware of the national debate about stem cells and many of us have already formed opinions about the subject.
Regardless of opinion, how many of us have considered the possibility that stem cell therapy might be able to cure our canine companions? Can stem cell therapy be used to "treat the untreatable" diseases for which modern veterinary medicine lacks effective treatments? Yes - It is possible. Terminal diseases that have the potential to improve with stem cell therapy include: degenerative myelopathy (German Shepherd Dogs, Pembroke Welsh Corgis and Rhodesian Ridgebacks), dilated cardiomyopathy (Doberman Pinschers, Boxers), idiopathic pulmonary fibrosis (West Highland White Terriers), metabolic disorders such as copper toxicosis (Bedlington Terriers), hypercholesterolemia (Miniature Schnauzers, Beagles) and ceroid lipofuscinosis (Tibetan Terriers, Dachshunds and others-also known as Batten's disease in humans). Because of the progressive nature of these diseases and the lack of alternative treatments, the idea of using adult stem cells to
replace dead and dying cells is an attractive option that our laboratory is currently investigating.Our laboratory is investigating the therapeutic application of adult stem cells in canine age related degenerative diseases, such as degenerative myelopathy (DM). DM is an insidious slowly progressive disease involving the thoraco-lumbar region of the spinal cord. DM occurs in middle-age to older large breed dogs and is most prevalent in older German Shepherd Dogs. Early clinical signs include: loss of proprioception (ability to sense limb position), ataxia (loss of motor function) and paresis (partial paralysis) of the pelvic limb. The initial presenting sign is usually abnormal nail wear and scuffing of the hind paws. The onset is subtle and the owner may not seek veterinary assistance for several months, believing that these early signs are related to joint diseases. Knuckling of the hind paws, dragging of the toes and exaggerated movements are usually present. The signs are usually bi-lateral, although one limb may be more affected than the other. A thorough neurological workup suggests a lesion in the spinal cord between T3 and L3. These clinical findings are suggestive of degenerative myelopathy. However, a slowly progressing disc extrusion with compression of the spinal cord can also have similar signs. Therefore, magnetic resonance imaging is necessary to differentiate DM from other spinal cord diseases such as disc protrusions and neoplasia.
Because the cause of DM is unknown, no specific treatments are available. Patients respond poorly to corticosteroids, nonsteroidal anti-inflammatory drugs, or vitamins. Some veterinarians recommend antioxidant therapy, but controlled studies have not yet been performed. The only medical management is heroic nursing care, going as far as training the dog to use a wheel chair (as shown in the photo). Note the leather boots on the hind paws to prevent abrasions on the hind paws. Sometimes diapers are necessary because of loss of bladder and bowel control. Owners need to be aware of the hopeless prognosis, although with supportive care and physical therapy, many dogs can be maintained satisfactorily for a period of time.
While degenerative myelopathy is considered untreatable, newer approaches using adult stem cells appear to offer hope. Adult bone marrow stem cells provide a reparative function following traumatic spinal cord injury. Adult bone marrow stem cells are isolated from bone marrow aspirates and then selectively amplified in tissue culture laboratories. Several laboratories have reported that when adult bone marrow stem cells are injected into a "bruised" rat spinal cord, a significant improvement in motor function is observed. The difference in motor function between non-injected and injected rats was quite dramatic with limb dragging or partial weight bearing, respectively. Other studies have demonstrated that embryonic stem cells will protect from neural insult and facilitate re-myelination of injured nerves. We believe that the beneficial effect of the adult stem cells is due to stabilizing damaged neurons rather than their differentiating into neurons and "rewiring" the spinal cord. Thus, if dogs are treated early in DM perhaps further deterioration could be prevented. None of these critical studies have yet been performed in canine patients with neurodegenerative diseases, although similar trials are currently being performed in human patients (a listing of approved human clinical trials using stem cells can be found at www.clinicaltrials.gov). Given the poor prognosis of many neurodegenerative diseases, many researchers are actively investigating stem cells for treating these untreatable diseases. Stem cells might provide their therapeutic action by replacing dead and dying neurons, stabilizing insulted neurons and preventing their death, or altering autoimmune processes that might result in death of neurons by some yet unknown mechanism. The good news is that stem cell therapy appears to be working sufficiently in rodents to justify clinical trials in human patients. Likewise, our laboratory has started clinical trials in canine patients with DM.
Unfortunately, if you have a dog that is afflicted with any of the above-mentioned diseases, it will take about three years to complete the critical clinical trials necessary to justify their use in canine patients. With the continued support of the canine community for clinical trials, the truly awesome therapeutic potential of stem cells will be realized as part of our continuing search to cure incurable diseases.

Dr. Richard Vulliet completed his PhD in pharmacology at the University of Colorado Health Sciences Center and his DVM at Colorado State University. Following service on the faculties of Texas A&M and Colorado State University, he moved to the School of Veterinary Medicine at the University of California-Davis in 1988 where he currently directs the Laboratory of Veterinary Cytotherapeutics. He is the recipient of CHF’s first stem cell research study grant. His current research is investigating the therapeutic applications of adult bone marrow stem cells in several canine diseases for which veterinary medicine lacks effective therapies.

[Editors Note: The CHF website contains a video prepared by Dr. Vulliet on degenerative myelopathy and another, How to Care for a Dog with Degenerative Myelopathy.]

Very interesting. Thanks for sharing.