Event: NIH Wednesday Afternoon Lecture
Subject: The Structural Basis of Ebola Viral Pathogenesis
Speaker: Erica Ollmann Saphire, Ph.D., Professor, Department of Immunology and Microbial Science, The Scripps Research Institute
Date: Wednesday, November 06, 2013, 3:00:00 PM
Dr. Collins: Good afternoon, everyone. This is a special day because we are in the first day of the NIH research festival and a special day because we have a remarkable lecturer as part of our regular Wednesday afternoon series who is here to teach us something pretty interesting about viral hemorrhagic fever, specifically Ebola virus.
Erica Ollmann Saphire has an interesting and very productive career bringing her to where she as a professor in immunology and microbial science at The Scripps Research Institute. We did a little digging and found a profile of her in the San Diego Union Tribune where she was called, the virus hunter and various comments were made about her contributions, which are obviously substantial. I won’t comment upon what they called her namely a steel magnolia. I thought that was odd to be putting in a profile of a scientist but you can decide for yourself later on.
She got her undergraduate degree at Rice with a double major in Biochem and Cell Biology and Ecology and Evolutionary Biology and then Ph.D. at The Scripps in the year 2000 and has been there in this remarkable productive enterprise focused on trying to understand how pathogens evade and usurp the innate and adaptive immune responses. She has quite a diversity of projects going on in the lab including Lassa and Marburg and Ebola fever and she is an expert in incorporating different approaches to understanding this, including immunology virology and X-ray crystallography.
So it is a great pleasure to have her here and I want to just point out that at the end of the lecture, we will have time for some questions and there are microphones in the aisle and again welcome to those of you who are watching on the web. We’ll try to be sure that questions are posed from the microphone so you can hear them and then at 4:00, we’re going to adjourn down the hall for continuation of informal conversations with our speaker but also the actual formal unveiling of the new FAES center, which I think you’ll want to come and have a look at because it is really quite beautiful facility and we’ll have a ribbon cutting, we will have a few hopefully short speeches and that will morph into a poster session where the scientific directors are actually themselves standing by their posters talking about their science giving you a chance to hit them up with really hard questions. So it’s going to be quite an afternoon.
But, to get us going here, let me ask you please to give a warm welcome to Erica Ollmann Saphire.
Erica Ollmann Saphire – Professor, Department of Immunology and Microbial Science, The Scripps Research Institute
Thank you, Dr. Collins. It’s a real pleasure to be here. My laboratory works on a lot of different viruses. Today I’m going to show you examples from two of them. The first one is Ebola virus, it’s a long filamentous Filovirus and the second one is Lassa virus – this is smaller rounder particle and it belongs to the arenavirus family.
Now what these viruses in common is a similar disease. They both cause hemorrhagic fever and the symptoms look quite similar especially at first. Whereas Ebola is thankfully quite rare, Lassa is unfortunately extremely common. There are hundreds of thousands of cases of Lassa fever every year in Western Africa and it’s the hemorrhagic most frequently transported to the United States and Europe.
Now what else these viruses have in common is a very small genome. Ebola encodes just seven genes; Lassa only 4. So whereas you have 20,000 – 25,000 genes and you can make 20,000, 25,000 proteins. These viruses make only a few.
So, using this very limited protein toolkit, how does this virus achieve all the different functions of the virus life cycle from attachment to a new host cell, fusion, entry, replication and coding, transcriptions, assembly and exit and some of the more sophisticated functions of immune evasion through lots of different pathways – how do they do that with only a very few proteins at their disposal?
This is the genome of Lassa virus. Those are at 7 genes; this is the genome — that was Ebola and this is Lassa, it’s 4 genes in RNA segments.
So how does a handful of proteins conspire to create such extraordinary pathogenesis in hemorrhagic fever? The answer is that each protein at these viruses do encode is essential. These viruses have no junk. Many of these proteins are multi-functional and some are extremely adaptable. By studying the proteins that these viruses make, we see the vulnerabilities of the virus, the Achilles’ Heel, the place where we can target a drug or vaccine or antibody.
But perhaps more importantly, we can understand something more about proteins themselves. Because evolution has compelled these proteins to be remarkable, to do more with less than other proteins. By studying what these proteins are capable of, we learn something more about the capabilities of proteins and molecular biology in general.