Last month when news headlines trumpeted the successful testing of a cat allergy vaccine, we spun it as a victory for all cats: Finally, allergies would no longer be an excuse for humans to avoid cats, and kitties could conquer the remaining holdouts, those homes that still aren’t occupied by America’s favorite pet.
Cats will be everywhere! Huzzah!
We were wrong.
Reader Kamala Tirumalai is not only an animal lover, caretaker of a feisty guinea pig and all-around awesome person, she’s also an immunologist with a PhD in microbiology. In other words, this is her area of expertise.
So we asked Dr. Kamala about the vaccine — which would be administered to cats, not people — and she was kind enough to give it some thought and explain why she doesn’t think it’s a good idea.
How HypoCat works
First, a refresher: HypoCat, a European company, created what it calls a “virus-like particle vaccine” “to induce neutralizing antibodies against Fel d 1, the major feline allergen in human subjects.” The vaccine was intended to “bind and neutralize the Fel d 1 allergen.”
In layman’s terms, the vaccine is designed to shut off the protein that triggers allergic reactions and symptoms like itchy skin, watery eyes and sneezing in humans. Contrary to what many people believe, the offending protein doesn’t come from cat hair, it’s produced in cat saliva and dander. But because cats are fastidious groomers, the allergen is passed from saliva to fur.
Vaccine administered to cats, not humans
HypoCat stops the protein, but there’s a catch: The vaccine is administered to cats, not humans, which means instead of inoculating people from the protein’s effects, it’s changing the way Fel d 1 operates in a cat’s system.
The problem, as Kamala points out, is that “Fel d 1’s function is still unknown.”
“Yet the fact that so many cat glands secrete it all the time implies it must have some function in and for cats,” she explained. “What if that’s a function important for their health? What’ll happen then to cats vaccinated against Fel d 1? That’s currently an unknown.”
By “neutralizing” Fel d 1 — in other words, making it non-functional — HypoCat could trigger an autoimmune response in cats not unlike human autoimmune diseases in which the body’s defensive systems turn on itself.
Tinkering with an unknown
In a paper published in the Journal of Allergy and Clinical Immunology, the Swiss-based company’s researchers acknowledge the unknowns surrounding Fel d 1’s function, noting while “some function in pheromone binding and pelt conditioning has been suggested, the biological function of Fel d 1 remains uncertain.”
More than 50 cats from labs in New York and Ireland were used in the study. The study’s authors say they split the subjects into different groups to analyze immunogenicity (whether the vaccine produced an immune response) and tolerability, but there is no long-term data on how HypoCat might affect house cats.
Then there’s the moral and ethical aspect. HypoCat makes a potentially dangerous alteration to cats for the convenience of humans.
“A vaccine given to cats to reduce their allergenicity for humans burdens them unnecessarily when human allergy to cats is primarily a human problem and should have a human solution in the form of reducing people’s cat allergies,” Kamala wrote. “Cats are perfect as they are. Why should they be the ones forced to change in order to be accommodated by a human whose immune system happens to have a problem with one of their proteins? This solution just doesn’t pass the moral smell test.”
Researching long-term impact on cats
In addition to moral qualms, there is very little data on how the vaccine will impact cats in the long term.
“Normal vaccines target pathogens to help our bodies make immune responses that stop them in their tracks,” Kamala wrote. “Obviously this one doesn’t do that. Instead it seeks to stimulate a cat’s immune system to target one of the cat’s own proteins. The worst unintended consequence could be flagrant autoimmunity in a cat vaccinated against Fed d 1.”
HypoCat could trigger a response not unlike human autoimmune diseases, in which the body’s natural defenses are turned on itself.
The only way to know for certain is to conscript additional cats for studies.
“This solution,” Kamala wrote, “passes neither the scientific nor the moral smell test.”