Human antibodies from survivors to kill Ebola viruses

In what could be termed as "silver bullet" for Ebola viruses, a team of researchers has isolated human antibodies from Ebola survivors which can neutralise multiple species of the virus that has killed more than 11,000 people in West Africa in the past two years.

Human monoclonal antibodies are generated by clones of a type of white blood cell that have been fused to myeloma (cancer) cells to form fast-growing "hybridomas."

Like heat-seeking missiles, they seek out and destroy their targets -- in this case, the Ebola virus, say researchers from Vanderbilt University Medical Centre and University of Texas Medical Branch in Galveston (UTMB) in a paper appeared in the journal Cell.

"This work suggests there are common elements across different groups of Ebola viruses. Maybe we can come up with one therapeutic or one vaccine that would solve all of them," "We thought we would need five different sets of vaccines or five different (drugs)," said James Crowe Jr, director of the Vanderbilt Vaccine Centre.

"In this study, a remarkably diverse array of virus-specific antibodies was isolated, which appeared to bind to various parts of the envelope protein of the virus," said professor Alexander Bukreyev from UTMB.

Some of the antibodies neutralised not only Ebola Bundibugyo virus, but also Ebola Sudan virus and Ebola Zaire virus, similar to that which caused the recent outbreak in West Africa.

In addition to neutralising multiple Ebolavirus species, one of the antibodies also protected guinea pigs from a lethal challenge of virus.

"This work points the way to using fully human antibodies as the next generation of antibody therapeutics," Crowe noted.

Ebola virus disease is spread by contact with contaminated body fluids, including blood and semen. It can cause massive bleeding. The death rate is about 50 percent.

The World Health Organisation (WHO) has reported 24 Ebola outbreaks since 1976, the largest of which is thought to have begun in Guinea in December 2013.

Of the 28,600 people who had been infected as of this month, 40 percent have died.

Several experimental Ebola vaccines and monoclonal antibody therapies currently are in development.