Feline immunodeficiency virus (FIV) causes AIDS in cats in the same way as the human immunodeficiency virus (HIV) does in people: by depleting the body's infection-fighting T-cells
Mayo Clinic researchers in the United States and at Yamaguchi University in Japan have developed a gene-based immunization strategy to fight feline AIDS and illuminate ways to combat human HIV/AIDS and other diseases.
They recently published their findings online in the journal "Nature Methods".
Cats were chosen for this gene experiment because they are much better models for testing AIDS viruses than are mice and other animals.
The scientists inserted one gene into cats that helps them resist the feline form of Aids. The antiviral gene came from a rhesus macaque monkey, and produces a protein called "restriction factor" that can resist Aids-causing viruses affecting other animals.
They also inserted a gene that produces a fluorescent protein called GFP. This protein, produced naturally in jellyfish, is commonly used in research to monitor the activity of altered genes. The gene expresses proteins that fluoresces (glows) when illuminated with certain frequencies of light.
The gene, along with the one for GFP, was introduced into feline eggs - known as oocytes. The oocytes were then implanted and the mother gave birth to the resulting kittens.
The researchers created three genetically engineered kittens that glow green, confirming that they have the restriction factor gene. The cats also pass this gene onto their offspring.
So far, Dr Poeschla's team has only tested cells taken from the animals and found they were resistant to FIV. But eventually they plan to expose the cats to the virus and see if they are protected.
"If you could show that you confer protection to these animals, it would give us a lot of information about protecting humans," the Mayo Clinic researcher explained.
The new research aims to mimic the way evolution normally gives rise over vast time spans to protective protein versions.
"One of the best things about this biomedical research is that it is aimed at benefiting both human and feline health," said Eric Poeschla, of the Mayo Clinic in Rochester, Minn., who led the study. "It can help cats as much as people."
The method of genetic modification is simpler and more efficient than traditional cloning techniques, and results in fewer animals being needed in the process.
Photo Credits: Mayo Clinic