Jun 2, 2017

Scientists develop blueprint for vaccine against deadly Lassa virus

CDC / Charles Humphrey

Scientists have discovered the structure of a key piece of protein that deadly arenaviruses use to enter and infect human cells. The research could help in developing a vaccine for Lassa fever and other related diseases, according to a decade-long study.

Lassa fever is one of three top vaccine priorities for the Coalition for Epidemic Preparedness. The viral hemorrhagic fever is endemic in West Africa, where it infects 100,000 to 300,000 people a year and can be fatal.

"The ten years of protein engineering to get there now provide the direct blueprints needed to make the right shape of Lassa molecule and display it on vaccines, and to begin to make the right shape of molecule for other arenaviruses," says Erica Ollmann Saphire, one of the study's authors from the The Scripps Research Institute.

Study details: The structure of a key protein on the surface of the virus, which is what antibodies from a potential vaccine could target, is not stable enough to study with x-ray crystallography, a standard technique for determining the atomic and molecular structure. Over ten years, the researchers worked to engineer different parts of the protein that they then assembled into a version that didn't fall apart. They then used x-ray cystallography to reveal the structure.

The structure: The protein consists of three sets of two-part subunits that come together like a tripod to infect the host cell. When the scientists tested antibodies from patients who had Lassa fever and recovered, they found that 90% of those antibodies that could neutralize the virus targeted the molecule at the tripod junction and basically locked the subunits together, preventing the virus from entering a host cell.

Lassa fever: The majority of infections occur in West Africa, where the primary agent is the urine or feces of an infected rat sometimes transmitted through contaminated food or air. The overall fatality rate for Lassa Fever is between 1 and 10 percent, but the rate among patients hospitalized with severe disease is between 50 and 70 percent. Notably, the disease is 90 percent lethal for women in the third trimester of pregnancy.

Go deeper

Updated 38 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 3 p.m. ET: 6,325,303 — Total deaths: 377,460 — Total recoveries — 2,727,679Map.
  2. U.S.: Total confirmed cases as of 3 p.m. ET: 1,820,523 — Total deaths: 105,644 — Total recoveries: 458,231 — Total tested: 17,340,682Map.
  3. 2020: N.C. governor says GOP should plan for a "scaled-down convention."
  4. Public health: Protests against police brutality threaten coronavirus response — Controlling the virus in nursing homes won't be easy.
  5. Business: More than 1 in 6 black workers lost jobs between February and April.
  6. Media: Interest in the George Floyd protests has soared past the coronavirus.
Updated 2 hours ago - Politics & Policy

Updates: George Floyd protests nationwide

Police officers wearing riot gear push back demonstrators outside of the White House on Monday. Photo: Jose Luis Magana/AFP via Getty Images

Protests over the death of George Floyd and other police-related killings of black people continued across the U.S., inciting a federal response from President Trump, the National Guard, Immigration and Customs Enforcement and Customs and Border Protection.

The latest: Immigration agents have been deployed to assist federal, state and local law enforcement. The U.S. Secret Service closed the streets immediately on all four sides of the White House Tuesday, until "riots become peaceful, or stop."

2 hours ago - Science

NASA passes the torch

Illustration: Eniola Odetunde/Axios

With the historic crewed SpaceX launch last weekend, NASA passed the torch to private companies that will need to step up to build the economy the space agency envisions in orbit.

Why it matters: This new era of spaceflight will likely be marked by new conflicts — possibly including product placement (like the Tesla that drove the astronauts to the pad on Saturday), safety concerns and cultural differences between companies, the space agencies and people they serve.