Saturday December 14, 2019

‘Trojan Horse’ Antibody Strategy Shows Promise Against Ebola Virus

Monoclonal antibodies, which bind to and neutralize specific pathogens and toxins, have emerged as the most promising treatments for Ebola

0
//
FILE - A health worker, center, takes the temperature of people to see if they might be infected by the Ebola virus inside the Ignace Deen government hospital in Conakry, Guinea, March 18, 2016. VOA

Scientists have found a hidden weak spot shared by all five known types of the deadly Ebola virus and successfully targeted it with two antibodies that blocked its ability to invade human cells.

In early-stage laboratory experiments published in the journal Science, the researchers developed a “Trojan horse” strategy that allows engineered antibodies to hitch a ride on Ebola to where the virus is most vulnerable before hitting it.

Follow NewsGram on Twitter

“The success in co-opting the virus itself to dispatch a lethal weapon … marks a turning point in the development of smart therapeutics against infectious diseases,” said M. Javad Aman, a scientist, and president at the U.S. biotech firm Integrated Bio Therapeutics who worked on the team.

Although years of testing lie ahead before any fully approved treatment might be developed for Ebola patients, Aman said similar strategies could also be devised against several other viral and bacterial pathogens.

No approved treatments

Ebola is an extremely deadly and contagious disease for which there are currently no regulator-approved vaccines or treatments. A vast outbreak of the Zaire strain of the virus, which causes haemorrhagic fever, killed more than 11,000 people and infected around 29,000 in West Africa in 2014-15.

Monoclonal antibodies, which bind to and neutralize specific pathogens and toxins, have emerged as the most promising treatments for Ebola. But a critical problem is that most antibody therapies — including the most promising experimental therapy, ZMapp — target only one specific Ebola virus.

Ebola Virus. Image Source: Wikimedia Commons.
Ebola Virus. Image Source: Wikimedia Commons

Follow NewsGram on Facebook

In this work, the research team found a way around this by targeting a weak spot — in the so-called lysosome of the cell — to where antibodies could hitch a ride on Ebola and deliver a punch that blocked the virus’ exit and ability to replicate.

The strategy could eventually be developed for use in a range of other viruses, the scientists said, including cousins of Ebola such as Marburg, and other viral diseases such as dengue or Lassa.

“It’s impossible to predict where the next Ebola virus outbreak will occur or which virus will cause it,” said Jon Lai of the Albert Einstein College of Medicine in New York City, who co-led the work. “We hope that further testing in nonhuman primates will establish our antibodies as safe and effective for treating those exposed to any Ebola virus.”(VOA)

Next Story

Vaccine Alliance GAVI to Invest $178 Million to Create Global Stockpile Ebola Vaccines

Vaccine group announce creation of ebola vaccine stockpile

0
Vaccine
There are similar stockpiles for vaccines against yellow fever, meningitis and cholera. Pixabay

The vaccine alliance GAVI announced Thursday it would invest $178 million to create a global stockpile of about 500,000 Ebola vaccines, a decision that health officials say could help prevent future outbreaks from spiraling out of control.

The public-private partnership includes the World Health Organization, UNICEF, the Bill & Melinda Gates Foundation and the World Bank, among others. The funding announcement was made after a meeting of GAVI’s board. GAVI said the investment, which it called an estimate, will be provided between now and 2025.

Since the current outbreak in eastern Congo was identified last August, health officials have immunized more than 255,000 people with a recently licensed vaccine made by Merck. To date there have been nearly 3,200 confirmed Ebola cases, including more than 2,200 deaths, in what has become the second deadliest Ebola outbreak in history.

Dr. Ngozi Okonjo-Iweala, chair of Gavi’s board, called the creation of the Ebola vaccine stockpile a “historic milestone in humanity’s fight against this horrific disease.” GAVI said “a coordinating mechanism” to decide how and when vaccines will be used will be established with partner organizations.

There are similar stockpiles for vaccines against yellow fever, meningitis and cholera. Those limited shots are doled out to developing countries by WHO, UNICEF, the Red Cross and Doctors Without Borders after receiving technical advice from others.

Ebola Vaccine Stockpile
A healthcare worker from the World Health Organization prepares vaccines to give to front line aid workers, in Mbandaka, Congo. VOA

The Ebola vaccine stockpile will be available to all countries, but only developing countries will be able to get vaccines for free in addition to support for the logistical costs of mounting vaccination campaigns.

Jason Nickerson, a humanitarian affairs adviser at Doctors Without Borders, said the new stockpile would change how officials respond to future Ebola outbreaks.

“Knowing how many doses of the vaccine exist in the world, and then being able to get a supply of them to high-risk countries in a very quick way, gives us another tool to respond to these outbreaks,” he said.

Earlier this year, the medical charity publicly called for an independent committee to oversee Ebola vaccination efforts in Congo, saying WHO sometimes used arbitrary criteria to determine who would get immunized. It said the fact that Ebola was continuing to spread despite the large number of people vaccinated was a damning assessment of the response.

Containing this outbreak has been complicated by violence and misunderstandings in a part of Congo that had never reported an Ebola case before.

Also Read-Measles Kills 140,000 people, WHO Calls it “Collective Failure”

Last week, response activities were suspended after attacks killed four Ebola responders, including a member of a vaccination team. Multiple rebel groups operate in eastern Congo and the region has been described as a war zone.

WHO has warned continued attacks on health workers and Ebola clinics could undermine attempts to curb Ebola and prompt a resurgence of the disease. (VOA)