Every year, hundreds of thousands of people in West Africa become infected with Lassa virus, which can cause Lassa fever and lead to severe illness, long-term side effects, or death. There are currently no widely approved treatments or vaccines for the disease. Now, scientists at Scripps Research in La Jolla, California have determined the structure of the critical protein complex that lets Lassa virus infect human cells. The research, published online on May 18, 2023 in Cell Reports, also identified new antibodies that bind to these proteins and neutralize the virus, paving the way toward more effective vaccines and treatments for Lassa virus. “This work is a big step forward in our ability to isolate new antibodies to relevant sites of vulnerability on the virus, and it provides a basis to conduct rational vaccine design to broadly protect people against many lineages of the Lassa virus,” says senior author Andrew Ward, PhD, Professor of Integrative Structural and Computational Biology at Scripps Research. “These new reagents described in the paper are already being put to good use and yielding exciting new results.”