Amid a deadly outbreak of Ebola virus in the western African country of Guinea, an international team of researchers has stepped up production of experimental antibodies that scientists say have the potential to cure people infected with the virus, which has a 90 percent fatality rate.
Twenty laboratories and research sites around the world, including in Canada, Japan, Israel, Uganda, and the United States are working simultaneously to develop manmade antibodies against Ebola virus. Antibodies are frontline immune system proteins the body makes naturally to fight illness when first exposed to an infection.
Immune system proteins targeting Ebola, when administered by injection, have a high cure rate in animal experiments, says Erica Ollmann Saphire, an immunologist with Scripps Research Institute in La Jolla, California.
“We have done a lot of experiments in non-human primates and if you can get the antibody into them within 48 hours after exposure, you can save nearly all of the animals. And even if you wait four or five days - say, someone that did not know they had been exposed - you wait four or five days for that animal to develop complete hemorrhagic fever, you can save more than half,” said Saphire.
Ingesting the disease
The disease, contracted through consumption of infected bats and tainted bush meat, quickly causes severe headache, fever and muscle aches before patients develop full-blown symptoms of vomiting, diarrhea and hemorrhaging.
The United States has contributed $28 million to an effort aimed at determining which of the half dozen or so antibodies being developed around the world are the most effective in fighting the deadly virus. A successful treatment for Ebola may ultimately contain a mix of several antibodies.
Saphire is leading the research effort, which is being coordinated by the Scripps Institute. She says normally, it takes several days for the body to make antibodies against an infection, time which most Ebola patients do not have.
“It is a way to make somebody immediately immune ... And so the idea is that we have gotten these antibodies either from cells donated by survivors or by immunizing mice, and we humanize the antibodies; we can just take these things that we have grown in cell culture and give them to you right now to protect you from your infection that you have immediately without, you know, having to wait four days,” she said.
Antibodies and virology
Saphire said limited supplies of the antibodies, so far untested in humans, have been sent to Guinea to help Ebola victims.
The global effort to develop an antibody drug against Ebola, Saphire said, is unique in the world of virology.
“And so that kind of the magnificent thing about this is that the whole field is contributing to the study to come up with the single best treatment available in the world. So, it is not going to be the Canadian treatment versus the American treatment versus competing labs. Everyone is on the same page in one set of ... experiments,” she said.
In the early stages, Ebola can be difficult to distinguish from other diseases that are endemic to Africa, including malaria and cholera. So, diagnostic tests also have been sent to Guinea and neighboring countries to aid in detection and efforts to treat those infected with the virus.