Homeland security menagerieLlama blood used in ebola assay

Published 8 May 2007

Unique protein antibodies can withstand high temperatures, a major challenge for health officials in the Third World

We rode llamas once, and it is not one of our favorite memories, so if this interesting biosensor technology results in a few of those silly creatures being knackered, we will not shed a single tear. In fact, we’ll be quite pleased about it, especially if it ends up working as advertised. Researchers at the Southwest Foundation for Biomedical Research say that antibodies in llama blood (as well as a few other mammals) can be manipulated to create a cheap and diverse biosensor capable of detecting such pathogens as ebola. You “can make them by fermentation in microbial systems and make a lot of antibodies inexpensively,” said researcher Clement Furlong. “You have extremely inexpensive reagents, so you can then develop technologies for Third World countries as well as First World countries.”

How it works: Unlike traditional mammalian antibodies — which are very good for detecting pathogens but sport heavy protein chains that cannot stand up to temperatures above 60 degrees — those in llama blood feature two light protein chains that remain functional even when exposed to temperatures as high as 90 degrees. “If they do unfold, they can actually completely refold on cooling and they can cycle over and over again,” said researcher Andrew Hayhurst. “For field use, where you don’t have very much refrigeration—in the developing world, for example—you could have an infinitely stable diagnostic assay for infectious disease.”