Green Glowing Cats Might Help In Hiv Research

Genetic Engineering Pioneered by the Creation of Green Glowing Rabbits

In 2000 the French geneticist Louis-Marie Houdebine captured headlines around the world with the creation of "Alba," a genetically modified white rabbit who had been given genes from a jellyfish that caused him to glow eerily in the dark.

Alba was created as a "work of art" inspired by contemporary artist Eduardo Kac, and forced to live in confinement for fear he would escape, breed with other rabbits, and create a race of green-glowing night-moving super-rabbits that could upset the balance of nature. Alba died in 2002.


More recently, Dr. Eric Poeschla of the Mayo Clinic in Minnesota announced that his research team had used the same genetic technology to create a green-glowing cat to assist in the eradication of feline HIV. Dr. Poeschla and colleagues took feline oocytes, or unfertilized eggs, and insert a gene from monkeys that would give the cat resistance against the feline AIDS virus. They also insert genes from jellyfish that allow the cat to glow green like a night light in the dark.

The hope of the researchers is that when the monkey genes are activated to fight the virus, the jellyfish genes will glow, telling researchers which parts of the cat's body are affected by the infection.

The Worldwide Epidemic of Feline HIV

Feline HIV (actually "FIV," since it is a feline virus, not a human virus) is a viral disease in cats that has effects similar to the AIDS virus in humans. Feline HIV can be transferred from cat to cat through blood-to-blood contact and nasal secretions. It can be passed from an infected mother cat to her unborn offspring. (A less severe infection, known as FeLV, is transmitted through sexual intercourse among cats and when they sleep together.) Humans are immune to feline HIV, and cats are immune to human immunodeficiency virus.

Like the human immunodeficiency virus, feline HIV can attach itself to the white blood cells known as macrophages, to another group of white blood cells known as T-cells, and to certain cells in the brain and spinal cord. As in humans, there is an initial flu-like illness shortly after infection, and then a period of recovery, although the disease-period is months or more often years in humans is just weeks or more often months in cats.

When the infected cat's immune system generates more white blood cells to respond to an infection, it creates more cells to be infected by the virus. The cat experiences bouts of open sores, diarrhea, and dehydration. Eventually the immune system stops producing defensive cells, and the cat either succumbs to infection or it is put down.

There are nearly 500,000,000 feral or "wild" cats in the world. Many of them, about 2 to 3 percent in Europe and the United States, are infected with the feline immunodeficiency virus. When these cats come in contact with cats who are pets, they can transmit the disease, which quickly spreads to other cats in the household or cats in neighboring households.

Preventing Feline Immunodeficiency Virus Infections in Your Cat

Veterinarians do not have a readily available test that can tell whether your cat has been exposed to the feline immunodeficiency virus. They only have a test that can tell whether your cat's immune system has responded to either an infection or vaccination. For that reason, just because a cat "tests positive" for FIV is no reason to have it put down if the cat may have been vaccinated. The test for FIV is done in the vet's office and only takes a few minutes.

Does the FIV Vaccine Work?

Scientists report good results with vaccines designed to prevent a single strain of FIV. A vaccine may be 100% effective against one of the strains of the virus. The problem with vaccinating cats against FIV is that there are two major subtypes of the virus, FIV-A and FIV-B, and a vaccination that is completely effective against one strain may be no use at all for another. Still, vaccinating kittens against the infection is likely to give many of the far higher quality of life, and every stray cat should be vaccinated before it is adopted into a home.

What Should You Do If Your Cat Develops FIV?

If your cat tests positive for FIV, and you know there has been no vaccination, then the reality is that the cat's immune system has encountered and created antibodies to the virus. Sickness and death of the cat, however, are not immediate.

Indoor cats may have many years of healthy and happy life even after they are exposed to this virus. It is important to keep the cat from infecting other healthy cats, but treating infections as soon as they are observed will help support longevity. Eventually, the cat will experience an untreatable infection, but there are cases in which that has only occurred 12 years after contracting the virus.

Just because your cat seems to show signs of FIV, such as sores, diarrhea, and frequent infections, does not mean your cat actually has FIV. Only about 15 percent of cats taken to the vet with possible signs of feline immunodeficiency virus test positive for the disease. And as long as your FIV-positive does not engage in rough play with other cats, chances are that they will not catch the virus, even if they have not yet been vaccinate—although it is better to vaccinate cats for FIV when they are kittens.

Will Glow-in-the-Dark Green Cats Come to the Rescue?

Two of three glow-in-the-dark cats at the Mayo Clinic have been mated and produced eight glow-in-the-dark kittens. As yet, however, the feline immunodeficiency virus researchers have only been perfecting their techniques for the future study of FIV resistance. They have confirmed that the jellyfish genes will make cells much easier to study under the microscope, and that tissue destruction from the virus will be much easier to identify in slides of tissues taken at autopsy.

The glow-in-the-dark cats have not, however, yet been exposed to the virus. The researchers do not know whether the monkey genes inserted into the parent cats have made them and their offspring immune. Ethical issues aside, it will be many, many years before all cats, both domestic and feral, carry monkey genes that make them immune to this deadly disease. In the meantime, vaccination and good care are the best answer for maintaining healthy and happy cats.