After an immunology postdoctoral fellowship at
Scripps Research, Saphire joined the faculty in the department of immunology as an assistant professor in 2003. She was promoted to associate professor in 2008 and full professor in 2012. In 2019, joined the faculty at the
La Jolla Institute for Immunology. Saphire is best known for her research on
Lassa virus,
Ebola virus and other causes of
viral hemorrhagic fever. Saphire was the first to solve the structure of the Lassa virus surface glycoprotein bound with an antibody from a human Lassa virus infection survivor. She went on to show that an experimental monoclonal antibody therapeutic "cocktail" could neutralize Lassa virus by targeting its glycoprotein complex. Saphire was also the first to discover the structure of the Ebola virus surface
glycoprotein and predicted that the Ebola virus receptor was located in the
endosome rather than on the cell surface. Later, she showed that the Ebola virus
VP40 matrix protein can fold into multiple distinct structures. Her laboratory has also discovered the structure of the glycoproteins of
Sudan virus,
Marburg virus,
Bundibugyo virus,
Lassa virus and lymphocytic choriomeningitis virus
LCMV. She also conducted field work in Sierra Leone to study the spread of Lassa virus. In recent work, Saphire determined the
cryo-electron microscopy structure of the
measles virus
fusion protein in complex with an antibody and determined that the antibody can trap the fusion protein in an intermediate state, thus halting fusion. == 2013-2016 Ebola virus epidemic ==