Human Protein Blocking Ebola Virus Growth May Lead to New Treatment

As the second-largest Ebola outbreak in recorded history continues to impact the Democratic Republic of the Congo’s (DRC) North Kivu province, investigators have made a discovery about how the Ebola virus interacts with human proteins, which could help lead to new treatments for Ebola infections.

In August 2018 an ethics committee in the DRC’s Ministry of Health approved the use of 5 investigational Ebola therapeutics for administration on an emergency basis outside clinical trials and as part of protocols for compassionate use, as there are currently no treatments or vaccines officially approved for Ebola. Now, in a new study published in the journal Cell, investigators report new findings about interactions between proteins of the Ebola virus and human host cells. The discovery sheds light on a way to block the growth of the virus that could potentially lead to the development of a novel Ebola treatment.

During their investigation into how Ebola virus usurps host pathways during infection, the investigators identified 194 human proteins that interact with Ebola virus proteins, some of which help the virus grow. In 1 interaction between virus and human proteins, the investigators found that a human protein called RBBP6 prevents interaction between the Ebola proteins VP30 and nucleoprotein, an interaction that is key to the virus’ reproduction. Based on their findings, the investigators say that a treatment mimicking RBBP6’s binding to VP30 may be able to disrupt the 2 Ebola proteins and stop the growth of the virus.

“It is frustrating that Ebola virus outbreaks continue,” Christopher Basler, MS, PhD, director of the Center for Microbial Pathogenesis at the Institute of Biomedical Sciences at Georgia State University and a study co-author, told Contagion®.

Dr. Basler also noted that, amid current outbreaks, investigators are working to understand how the virus grows, how it causes severe disease, and how components of the host cell interact with the virus. “Our finding suggests a novel approach to develop potential treatments, but because things are in very early stages it is not realistic to think that our findings will help address the current outbreak. We hope that we can use our findings to address future outbreaks.”

Gaining a more comprehensive understanding of how the viral proteins interact with the host cell proteins will be key to understanding why the virus causes disease and will aid in the search for new ways to block virus growth, Dr. Basler explained. “We are continuing to study how RBBP6 affects Ebola virus and why. We are also exploring ways to develop drugs that will mimic the inhibitory effect of RBBP6 but block the virus more completely.”

The DRC Ministry of Health released an epidemiological update on the situation on December 17 indicating that the outbreak has now reached 539 cases. This includes 491 confirmed cases and 48 probable cases. The outbreak has so far led to 315 deaths—267 confirmed and 48 probable—and 186 recoveries, all occurring in the North Kivu and Ituri provinces in the country’s northwest region, including the city of Butembo, which has more than 1 million residents.

Armed conflict and violence occurring in the city of Beni, which has been hardest hit by the current Ebola outbreak, continue to hinder surveillance, disease prevention, and other response efforts by the Ministry of Health and other public health agencies. In a ring vaccination campaign that began with support from the World Health Organization in the country on August 8, a total of 48,048 people have received Merck’s unlicensed Ebola vaccine. Other infection prevention measures have included the addition of new handwashing stations in the affected areas and providing safe and dignified burials for victims of the outbreak.

For the most recent case counts associated with the 10^th Ebola Outbreak in the Democratic Republic of the Congo, check out the Contagion® Outbreak Monitor.