Malaria vaccine in A&M goats’ milk could save lives
By Lana Berkowitz
Updated 07:39 a.m., Saturday, March 3, 2012
Goat No. 21 was not pleased to be singled out from the safety of her herd for photos. She tried to twist away while the Texas A&M researcher kept a firm grip on her horns.
The wrangler did not hold her long because no mother-to-be needs extra stress. And No. 21 is special.
The so-called “pharm animal” has been genetically modified to carry a malaria vaccine in her milk, a development that has the potential to change life in impoverished countries.
When the black, brown and white nanny gives birth – maybe to twins – this month, staffers at A&M’s Reproductive Sciences Laboratory will celebrate, then push ahead with their research.
“Our ultimate, ultimate idea is to continue the research to the point to where you actually have a herd of goats that are producing vaccines, pharmaceuticals and nutraceuticals … in their milk,” A&M professor Mark Westhusin said, envisioning a day when children can “just go out and drink the milk and get vaccinated.”
The process from testing to trials and approval could take 10 years.
Malaria, a mosquito-borne disease, killed about 655,000 people in 2011, according to the World Health Organization. The Institute for Health Metrics and Evaluation at the University of Washington puts the death toll much higher: 1.2 million.
Bioengineered animals could be life-savers for Third World countries that cannot afford to build multimillion-dollar facilities to produce vaccines, according to Westhusin and associate professor Charles Long.
Goats are indigenous in all the major impoverished areas, Westhusin noted.
“They are easy to keep. They can eat a beer can and turn it into protein and milk,” he said. “They are just great animals in terms of what they offer to impoverished countries.”
The vaccine currently is in a form that must be isolated, purified and injected, researchers said. A&M will send No. 21’s milk to GTC Biotherapeutics for continued testing and trials.
The Massachusetts-based firm originally developed the transgenic malaria vaccine, which proved effective in mice, said William Gavin, GTC vice president of farm operations and chief veterinarian.
The word “transgenic” means “transferring or having genes from another species.” To create the malaria vaccine, DNA coding for the malaria parasite is introduced into the goat genome linked to milk production. The new DNA switches on in the mammary gland only when the animal produces milk, according to GTC.
Although the vaccine was developed 10 years ago, research was put aside when funding was lost. It resumed when Reproductive Science Lab scientists working with the A&M College of Veterinary Medicine and Texas Agrilife Research began a partnership with GTC in 2010. A&M hopes to find new funding.
The three goats in A&M’s project are an Alpine cross of European dairy breeds chosen for their smaller size and generous milk production.
Through the collaboration with GTC, A&M received embryos to implant into surrogate mothers. When the female, No. 21, and male kids No. 17 and No. 19 were born within a day of each of other, it was soon verified that they were carrying the malaria antigen. When No. 21 was 9 months old, she was bred with friendly chocolate brown No. 17.
Not everyone in favor
The Humane Society of the United States and other animal welfare activists have spoken out against the use of pharm animals, but Westhusin has little tolerance for opponents of biotechnology.
“When haven’t we been messing with nature?” he asked, noting that 80 percent to 90 percent of the corn, soybeans, cotton and vegetables produced in the United States have been genetically modified for years to resist disease and insects.
A&M’s Long said he considers it arrogant for those in the developed world to criticize animal biotechnology.
“Millions and millions of people are trying to make sure their kids don’t die before they are 5 years old. You’ve got to look around. It’s not right,” Long said. “If a person chooses not to … use a vaccine that was generated in a transgenic animal, I’m all for that. But you shouldn’t make that decision for other people around the world.”
Most other malaria projects are using cell culture methods to produce antigens. The PATH Malaria Vaccine Initiative is a global program established with grants from the Bill & Melinda Gates Foundation. Researchers at the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, also are doing studies.
“So everybody recognizes that no one approach is going to be a silver bullet, so to speak,” said GTC’s Gavin. “We are the only ones using transgenics – and the goats.”