Department of Veterinary Medicine

Cambridge Veterinary School

Call for cases: Spinal cord repair following injury in dogs

In 2005 we demonstrated that olfactory ensheathing cell transplantation was reliable and safe in dogs with spinal cord injury (SCI). The Department of Veterinary Medicine has now received major support from the Medical Research Council to conduct a phase II clinical trial in dogs with SCI. The aim is to assess the benefits of the therapy in our patients.

Molly awaiting her turn as the first patient on our trial. The cells constituting the graft are injected into the spinal cord (orange arrow). MRI and X-rays are used to guide the injection.

The project is currently been undertaken by Nick Jeffery and Nicolas Granger both Diploma holders in Veterinary Neurology. Nick Jeffery has more than 20 years’ experience in treating spinal cord injury in small animals and is guiding this new trial. Nicolas Granger is in charge of the day-to-day running of the project. We have a full-time veterinary nurse, Helen Blamires, to assist with the project.

Is your dog a potential candidate?

We are currently looking for dogs with SCI to be included in the trial. For inclusion, dogs have to meet the following criteria:

  • Weigh less than 20kg
  • Have a suitable temperament for taking part in the functional evaluation exercises (see below)
  • Have a spinal cord lesion located between the front legs and the back legs that was caused by an acute traumatic episode such as a fracture, luxation or intervertebral disc extrusion for example
  • Have reached a static, unacceptable stage of neurological recovery (for instance, complete loss of motor and sensory function to the pelvic limbs and/or incontinence) for a minimum of three months following the initial injury
  • As owners, you need to be able to bring your dog in monthly for evaluation over a six month period and then for the final evaluation at one year

Cell Collection and Culture

Following the earlier safety and feasibility studies, we know that OECs can be biopsied and cultured effectively from the lining of the nose (olfactory mucosa). Your dog will need to have a surgical procedure to have the biopsy taken under general anaesthetic. Dogs will have to stay in the hospital for two to three days after the procedure so we can control (the limited) post-operative pain. Our previous experience has not detected any detrimental effect on smell or behaviour following this procedure and dogs quickly recover, usually eating the same day.

These cells are then cultured over three to four weeks to reach sufficient number before being injected directly into the damaged region of the spinal cord of your dog. An MRI scan is used at that time to determine the centre of the lesion and injections are made through the skin under X–ray guidance to ensure accurate placement.

During the trial, we need to compare the injection of the cells to another treatment. Thus, one of two treatments, both shown to give functional benefits, are randomly allocated to the dogs. The second treatment contains various factors that help preserve the health of nerve cells. Each dog is entitled to receive both treatments, meaning that your dog can receive the alternative treatment at the end of the first six months evaluation.

The Queen's Veterinary School Hospital has state of the art facilities. Canine olfactory ensheathing cells in culture, stained here in red.

The Functional Evaluation Exercises

The three main tests used to measure the outcome are:

  • Gait analysis – reflective markers are placed on the dog’s hair and infrared cameras are used to record and analyse their gait on a treadmill
  • Spinal cord conduction – small needle electrodes are placed under the skin (under sedation) and used to measure the electrical flow in the spinal cord
  • Continence evaluation – a catheter is placed into the bladder to record the bladder function during contraction

These exercises are carried out before the transplantation surgery (so we have a baseline for each dog) and then at monthly intervals afterwards.

Spinal cord electrical activity is recorded via small needles placed under the dog's skin(red and blue cables on the photo). A Dachshund with hind limbs paralysis during continence evaluation. Molly during gait analysis. Reflective markers are stuck on her legs.