Stem Cell Science: Can It Help Pets?

Stem cell therapy, often referred to as regenerative medicine, has grown in popularity in veterinary circles as a way to treat many painful issues that affect the wellbeing of dogs, cats, and horses.

Bosco was having difficulty walking and generally moving about. The 8-month-old Labrador Retriever was taking anti-inflammatory medication daily as well as glucosamine-chondroitin supplements, but his level of activity had been reduced to short leash walks. His owners took him to Adam Gassel, DVM, at BluePearl Specialty and Emergency Pet Hospital in Irvine, California.

“Based on CT scans, he was diagnosed with bilateral elbow dysplasia with displaced fragmented medial coronoid processes and secondary osteochondral defects on the humeral condyle. Unfortunately, this disease is progressive,” Dr. Gassel says. “I recommended bilateral arthroscopy and regenerative stem cell therapy.”

Bosco consequently underwent arthroscopic surgery on both elbows and autogenous fat was collected during the procedure and sent to the VetStem Biopharma laboratory where technicians produced stem cell doses for the dog.

The plan was to do surgery and see how it went before administering the stem cells. Eight months after the procedure, Bosco was still slow to get up and in pain, so his owners asked Gassel to proceed with intravenous injections of the stem cells.

Within two months of his injections, Bosco came off his daily anti-inflammatory medication and his owners were able to gradually increase his activity levels, which Gassel carefully monitored over the next 12, 18, and 24 months. They reported that Bosco showed no signs of lameness and was able to run and jump normally.

“I received a phone update from the owners three years following Bosco’s initial treatment and his owners reported that he is still doing great and running around and acting like the goofy Lab again,” Gassel says.

Dr. Gassel has been performing stem cell procedures since 2008 and says approximately 75 percent of patients that he has treated for a condition such as osteoarthritis responded to the treatment.

Response can range from improved quality of life to dramatic reduction in lameness, discontinued use of current medications for arthritis or decreased dependency on their use. “I spend a lot of time during the consultation to try and set realistic expectations for owners,” he says.

Stem Cell History

The first cell therapy treatments, in the 1930s, were intended to slow the aging process. The term regenerative medicine was brought into popular culture in 1999 by William A. Haseltine, Ph.D., when he coined the term during a conference at Lake Como, to describe “interventions that restore to normal function that which is damaged by disease, injured by trauma, or worn by time.”  Today, Dr. Haseltine’s “buzzwords” apply to both humans and pets.

Professor Boaz Arzi, DVM, DAVDC, DEVDC, FF-AVDC-OMFS, professor of dentistry and oral surgery and director of the Veterinary Institute for Regenerative Cures (VIRC) at the University of California, Davis, says regenerative medicine is “an innovative branch of medicine that uses stem cells and tissue engineering to develop novel therapeutics to repair or replace diseased organs, tissues or cells.

“Harnessing the various aspects of regenerative medicine, we can now attempt to treat disorders that were previously regarded as non-curable or untreatable and offer exciting possibilities for development of future therapies,” he explains.

Under Dr. Arzi’s guidance, VIRC has enrolled and treated hundreds of cats, dogs, and horses in clinical trials using FDA-compliant methods to reliably and safely produce mesenchymal stem cells (MSCs) as treatments. Stem cell therapy may be suggested to help with osteoarthritis causing pain in hips and knees, to help repair torn ligaments, and for renal disease and canine atopic dermatitis. It’s also used to treat irritable bowel disease and other immune-mediated conditions.

Trials and Treatments

In addition to one-on-one treatments such as Bosco received, laboratories are also working to trademark and patent specific stem cell therapy treatments, based on cells that target and heal precise areas of the body. Often, such work involves trials in conjunction with work being done by university researchers.

Arzi and his research team have been conducting trials since 2013 to find a cure for feline chronic gingivostomatitis, a painful disease in the mouth that makes it difficult for cats to eat and drink normally.

“Feline chronic gingivostomatitis is a naturally occurring immune-mediated oral mucosal disease potentially triggered by a viral etiology such as feline calicivirus,” he says. “It results in painful inflammatory mucosal lesions that markedly affect quality of life and often requires long-term immunosuppressive therapy [steroids] in cats that don’t respond to dental extraction therapy.”

An important part of any trial is to ensure that stem cells can be shipped and administered safely within a 24-hour period without any degradation and this was successfully achieved early on.

In the early phases of the FCGS trial, first conducted only at UC Davis and later extended to Cornell University and two private veterinary practices, cats were given adipose-derived mesenchymal stem cells (ASCs) harvested from both individual feline patients (autologous cells) or donated from another cat (allogeneic cells). Researchers discovered that in about 50 percent of cell cultures—the process of producing stem cells—the ASCs were dying during production. Further research showed that the cells contained Feline Foamy Virus, a retrovirus commonly found in about 50 percent of cats. So Arzi and his team switched over to exclusively using donor cells obtained from healthy cats.

“The results showed a 72 percent positive response rate within three to six months. One of the cats was 12 years old at the time and lived pain-free and cured of the disease until he was 20 years old,” Arzi says. “The goal now is a 100-percent success rate.”

Commercially Available Stem Cell Treatments

VetCell Therapeutics USA in Santa Ana, California, has also been working on a specific stem therapy geared to treat FCGS and are currently conducting trials with Arzi and his research team. The goal is FDA approval for the therapy so it can be made commercially available on demand for veterinarians. (A commercial stem cell treatment is not made in huge batches and stored but made to order.)

“Our goal is to enroll 200 cats in this current trial,” said Chad Maki, DVM, chief veterinary medical officer for the company. “This product is for cats that haven’t responded to medication and also have had teeth extracted, still with no positive results,” he says.

Trials are currently being conducted in Los Angeles, San Francisco, Portland, Oregon, and Minneapolis, with more locations to follow, and enrollment is open at https://www.vetcelltherapeuticsusa.com/fcgs_trial/. Cats enrolled in the trials receive two doses of 20 million stem cells each four weeks apart, and the cost of the therapy is free to the participants.

How Stem Cells Are Gathered

Mesenchymal stem cells, the most common type used in veterinary treatments, can be harvested from bone marrow or organ material removed during a regular spay and neuter procedure. However, it’s becoming the norm for companies in the veterinary stem cell field to focus their stem cell treatments on stem cells harvested from fat, known as adipose-derived stem cells. Cells harvested from fat are considered heterogeneous cells – a mixture of cells with many functions that can be used in many different applications.

“The number of cells in fat is greater than that in bone marrow,” says Bob Harman, DVM, CEO of VetStem Biopharma in Poway, California. “The fat can be taken from anywhere on the animal. The most common way to collect on dogs and cats is to make an incision similar to a spay and remove fat from the abdominal cavity under general anesthesia.”

In the case of larger animals such as horses and very large dogs, fat removal can also be done by liposuction.

To safely collect and transport harvested fat, the laboratory provides a kit to the pet’s veterinarian, which includes an insulated shipper, ice pack sample transport tubes (for the fat), and necessary paperwork and shipping labels. Stem cells to be used in the animal are created in the laboratory and shipped back to the pet’s veterinarian under stringent conditions to be injected in the appropriate site.

Cost and Pet Insurance Coverage

Because pet health options frequently mirror human health options, costs are similar. Prices for stem cell treatments for pets vary but expect to pay between $2,500 and $4,500. That cost can be reduced for people who purchase pet health insurance. Currently, while human medical insurance companies balk at paying for stem cell treatments, pet insurance companies are already paying out for some stem cell therapies.

According to Karen Davis, a spokesperson for Nationwide, pets covered by the company’s Whole Pet with Wellness Plan are eligible for stem cell therapy treatments for the following conditions:

– Intervertebral disc disease (spinal cord compression/decompression).

– Hip dysplasia.

– Spondylosis (immobility of the spine due to formation of bony spurs along spine bones).

– Cruciate ligament injuries.

– Osteoarthritis.

Banking Stem Cells

A company called Gallant recently snagged financial backing on Shark Tank to help finance production of stem cell harvest kits that allow a new puppy owner to bank a dog’s own stem cells from the removed testes and ovaries acquired during a standard spay or neuter surgery.

“Instead of literally disposing of the removed organ material, the kit allows the veterinarian to save the organs and ship it to us for the stem cells to be extracted, frozen, and stored should the pet require them later in life,” says Gallant’s founder Aaron Hirschhorn, himself a stem cell therapy alum, having received stem cells to heal a debilitating back injury. The kit costs $395 dollars and lifetime banking of cells costs $595.

“The results of my own stem cell treatment were life-changing in more ways than one. It made me pain-free and it’s what prompted to me make stem cell banking available to pet parents,” he says.

Banking stem cells harvested during a routine spay or neuter is no different than parents banking a baby’s umbilical cord blood, should the child require stem cell therapy later in life.

According to Dr. Linda Black, DVM, Gallant’s chief medical officer, the benefits of collecting stem cells during the spay or neuter process is that the stem cells are still young.

“We want to cryopreserve the cells while they’re still young because they are more powerful than older stem cells,” she says. “The frozen cells do not lose their efficacy over time.”

This article was reviewed/edited by board-certified veterinary behaviorist Dr. Kenneth Martin and/or veterinary technician specialist in behavior Debbie Martin, LVT.

Sandy Robins is an award-winning pet lifestyle journalist and author of For the Love of Cats, Fabulous Felines: Health and Beauty Secrets for the Pampered Cat, The Original Cat Bible, and Making the Most of All Nine Lives: The Extraordinary Life of Buffy The Cat.
Top photo courtesy VetStem Biopharma