The second American health worker infected with the deadly ebola virus in Liberia arrived in the U.S. today. Nancy Writebol and Dr. Kent Brantley are both being treated at an isolation unit at Emory University Hospital in Atlanta.
As part of their treatment, both received an experimental serum before they left Liberia. Andrew Pekosz, an Associate Professor of Microbiology and Immunology at the Johns Hopkins University Bloomberg School of Public Health, joined Take Two for more.
On the serum itself:
"It sounds like this is one of a new category of treatments, where antibodies against the virus are produced in plant cells, so you can get high amounts of very pure antibody and then you can give those antibodies to a patient. Usually, that is an effective way of getting the virus to replicate less efficiently and then allowing your immune system to catch up and clear the infection completely. From what I understand, it has been tested in animal models and so the approach has been proven to be feasible. But, there have been no human clinical trials of this done to date."
On how the serum works:
"Tobacco cells turn out to be very easy to transfect with pieces of human DNA and express large amounts of proteins. So basically, what people have done is they've worked out ways to express a whole range of human proteins in tobacco cells, antibodies being one of the largest class of proteins. So you can introduce the gene for a particular antibody into the plant cells, as the plant grows, it produces this protein, and to simply harvest the protein, you simply clip the leaves off, put it in the blender, and in a relatively simple manner you can purify large amounts of this antibody away from the plant proteins. "