How Ebola Virus Avoids the Immune System (IMAGE) University of Pennsylvania School of Medicine Caption Scanning electron microscope image of Ebola virions (spaghetti-like filaments) on the surface of a tetherin-expressing cell (center). The other three cells seen in this image (upper right and upper and lower left) do not have the filamentous virus on their surfaces. Credit Paul Bates, Ph.D., University of Pennsylvania School of Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.