hepatitis

>> good afternoon. we'll get started. as you can all tell, it's virtually springtime, summertime outside and it's also something -- >> [indiscernible] >> how's that? thank you.

okay. so it's springtime, summertime and that has many recollections. and i'd like to briefly share one with you as a sort of unusual introduction to today's topic. but i hope you'll see where i'm getting.

so this symbol of course is the brooklyn bridge. one of the two most famous structures in brooklyn and one that has lasted, and those of you who have been coming to this course repeatedly have heard this song over again but it's sort of the metaphor that

symbolizes bridging, basic science and human health. i've been handing out wrong information for several weeks. that's actually manhattan on the other side, not brooklyn. and the tallest building is the trinity church. for those who called my

attention to it, i stand ected. now, this is the baseball season, and it's just started. and it's very exciting and the other great symbol of brooklyn is abbott's field which is now a giant housing thing. there's a little plaque on the

ground and you talk to people do you know what was here, nobody has the faintest idea. but this is the world champion brooklyn dodgers in 1955. the next slide shows fourf the big stars as jackie robinson, next to him is duke schneider and next to him is pee wee ruiz

and next to him is harvey alter. [laughter] i don't know who the fourth person is. maybe some experth can help me out. why hould i be showing baseball pictures. it's very simple.

because the most important person in the basebatheme aside from the pitcher and the coach and everybody else is the number 4 hitr because somebody in the first three is supposed to get on base and the number four hitter is the guy who hits the home run.

so th is a long track in a way of saying that today we have two number four hitters. and this is no joke. we're really very grateful to both of you for coming. and i hope we all will benefit from exciting new things that we're going to hear.

so the first of our speakers today is jake liang ho got his medical degree at harvard medical school. and is here at nih as the chief of the liver disease branch. jake has been extremely productive in leading a group that's involved in the exciting

developments with hepatitis c virus. which who knows, maybe the first chronic virus infection of man to be cured by dru, we'll see. we'll hear about it. an enormous problem jake and his colleagues have done outsiding work in the molecular, cellular

and also at the clinical level. our second speaker is harvey alter who is chief of the clinical studies and associate director of research in the clinical center. and in the department of transfusion immediateson. harvey is famous because after

his graduation from rochester school of immediate isn't he came to nih as an investigator, as a clinical associate. and played a significant important role in the discovery of australia antigen which was the first clue for the identification of hepatitis b

now you may not think of it, but in those days if somebody went and had to have a blood transfusion, the chances of getting hepatitis were very high particularly if you had more than one transfusion. and there was some knowledge that there were at least two

major kinds, one you got from water and contaminated food and that turned out to be hepatitis a of course. and then there were others that were transmitted throu largely blood. and the first one identified was hepatitis b.

and mar -- harvey played a critical role in that and applied the knowledge to the blood bank whose name you'll hear eliminated a big portion of this post transfusion hepatitis. but he wisely recognized that the were other viruses. and then played a it critical

role in the description of so-called non-a non-b which turned out tobe hepatitis c which we'll hear much more about later. now, in recognition of these findings, harvey has received the alaska award enumerable awards from organizations around

the world and most recently received a very prestigious award from canada. and so harvey's going to talk about a new virus about which maybe many of you haven't heard. the alphabet has expended beyond b to e and a little beyond. but he's together to discussion

the question of e virus and its relationship to the blood bank. when you think of it, the blood bank is something on which our lives in medicine depend. there's no substitute. yet, it's been a long time there's always the question of does something creep into the

blood bank that can then cause epidemics and serious illness among people who get tranusions. is it possible to predict that? or if you find something, how do you find out whether it actually causes disease. so these are some of the

problems that will be discussed. so thank you very much, and jake, if you would again. >> can you hea me? thanks for that kind introduction, and when you showed that picture of brooklyn bridge i wasn't sure what he was trying to do.

i thought he was going to try to sell the brooklyn bridge because he could do that. harvey also is probably more appropriate to talk bit because he's clely one of the pioneers in discovering hepatitis c virus but he was kind enough to let talk about hepatitis c and take

a new adventure on hepatitis e. without further adieu, i came up with this title probably because i felt that since this is a series on demystifying medicine, i should come out with a mysterious title and then try to explain it. in the second, i think this is

something actually somehow inspired me what i have done which hopefully i'll share with you my thoughts. as you heard, hepatitis c is a major public health problem, more than three million american people infected with hepatitis c.

and globally 170 people infected with hepatitis c. this is not only the major cause of chronic liver disease in the world but also one of the human viruses has been looked etiologically. if you look at the trend in the last decade or so -- 20 years

ago and really took many years after that was discovered in 1989, and the virus cloned molecularly by michael and his colleague -- our own harvey alter and ben bradley at cdc, this would not have been possible. this is a member of flaviviridae

family. and there are 30% sequence variations. high mutational rates certainly in the blood and what's quad quaspecies. and high rate of chronicity 70 to 80% people infected with this virus will develop into chronic

infection despite active immune response. also about this infection that has a silent disease progression most of the people with this infection don't even know it. if they don't have end stage liver disease will they become symptomatic.

i'm going to come back to it although most of my talk today will not be on -- hopefully you'll get some inkling on what we do. the virus has evolved with a host with hundred of years or for ongoing infections. the virus first infect the host

through a series of highly coordinated and sequential steps. first of all virus gain entry into the cells by interaction with very different post doctor so-called entry factors. and then the virus is then released and traffic the area

of, let me get this working, of er in which the -- translated into poly protein. and then together with membrane derived from the er forming this so-called replicated intermediate contracts in which the viral replication occurs. and then most infrequently

through organelle in the lifer called lipid droplets that's where they first assemble. from there the virus in complex lipo proteins releases into circulation alternatively it could spread to the adjacent cells without going through the circulation.

so let me go back to my title. so what is zero day. for those of you who know what it is, let me play it out. and so there are several multiple choices. is it your birthday, is it the day your bank account balance is zero or the day you feel your

life is a big zero i think that may be favorite answer for dr. alter but i'll ask him related to the academy award nominee zero dark 30. or september 2011 or is this what ground zero is named. the last three is close to the answer.

in today it's a cyber space lingo. it reflects a vulnerability in the software of a computer that is unknown but can be exploited by hacker to break into the system. the most common technique that hacking is called fuzzing.

fuzzing means you input random data into applications that force them to crash. what you do is you would document all the crashes and trying to figure out where the crash occur and eventually to fool the computer to reveal this vulnerability for a way to hack

into the computer. this is how most of the hackers can hack into very complicated sophisticated computer system. and although i'm not a hacker but this concept is intriguing. so how can we apply this so-called zero day for hepatitis again actually this is not

really not really new. such a conceptually has been really proposed many years ago. a nobel laureate had made the statement that in the face of great complexity randomness is not an irrational process. so how can this concept of hacking randomness introduce

help -- hepatitis c. if you introduce so-called random perturbens to perturb the system into virus infected cells to force the virus to pa have differently just like you force computers behave differently. in order to reveal the secret and identify its vulnerability.

i think in the rest of my talk, i'm going to share with you three vignettes in which i'm going to apply three type of perturbguns with perhaps better treatment for the virus. it's small interference rnas micro rnas and chemical probes.

and interferon for proturbens. these are highly useful tools that you can specific using this concept of perturbagens initiated an acv host interactions by genome-wide sirna screen. this work was done in collaboration with harvard

medical school institute of chemistry in cell biology who had the screening facility for sirna. you have array pools of sirna representing 20,000 human genes in the human genome and them transect it into cells and once you knock out these genes you

infect the cell with the virus and later you will harvest the cells. the cells you will use either for staining for the viral protein or staining for nuclei by automated imaging technology. the second step or part to take the first step and transfer on

to naive cells ask then go through the same procedure. as you can see part one and part two actually looking at different stages of roi cycles. so you think this technique was able to identify a whole series of what we call host factors that can facilitate infections

or host anti-viral factor that can inhibitor hcv infection. this is just image representation of these staining. as you can see, these are the staining with the viral protein. this is a dna working the nuclei.

this is the positive control this is the negative control. you can see that host factor has significant decrease staining -- these can be quantify by automated image analysis and provide you with a database for analysis, to identify what's so-called hpf and haf.

so using this technology as well as combining bio -- harvard medical school was able to generate a complicated hcv interaction map as shown here. i won't take you through it but the one node there which represents the gene i take alpha called chuck inhibitors with a

capital b kinase alpha represent a very critical interaction point of how hcv interacts with the host. so frank took on an ambitious process -- first of all what he had done is take this out with -- as i mentioned with you before srna was used with a

pool. he wanted to test whether these individuals srls will work. interesting yes individual srna work -- their potency koar late very well with the silencing efficiency of individual srna. so it's very consistent indeed with the silencing lead to

decrease hcv replication. furthermore he overexpressed the cells with expression factor containing ikk alpha and he was able to see significant increase in viral productions with hcv infected cells. and the infected virus in the culture medium.

in the converse using ikk alpha mutant which is deficient in the kinase domain, this behaves as negative dominant construct was able to significantly decrease the viral replication of the hcv infebruaried -- infected cellas well as infected virus. as you well know n kappa b is

only a very important pathway in many biological facets. there's been a lot of pharmaceutical industry in developing androgens in kappa b. we're able to get several of these drugs that are specifically targeting ikk complex.

two of the inhibitors will target, were active against all ikk. i'll tell you there's -- ikk. but once we thought will target ikk beta not ikk alpha. so testing these inhibitors show that these two inhibitors that general ikk inhibitor were able

to significant reduce bile production in a dose dependent manner whereas this inhibitor targeting ikk beta only had known the fact in primary human hepatocyte. he saw the same phenotype of these inhibitor in sort of blocking hcv replication.

so let's quickly review kappa b and you'll know that is discovered by baltimore in a nobel work. this was a process that in response to external stimuli, activate this massive switch n kappa b so-called ikk complex composed of alpha, beta and

gamma. phosphorylation of this complex will then activate this which will further phosphorylate this inhibitor of ikk beta here that basically keeping the nf kappa complex dormant in the cytoplasma. phosphorylation of it k beta

will lead to degradation, release the n kappa b complex in the nucleus to activate n kappa b responsive genes. so this is in a short, in a short how nf kappa b works. in terms of the virus, what the virus did is that through either receptors or -- -- that waspart

of the anti-viral response involving other factors such as -- 7 and 9 and leads to the introduction of the interferon pathway. the ikk beta and gamma are the activators of the n kappa b it's essential for ikk alpha has been implicated in michael

karen's group to mediated so-called non-conical pathway to n kappa b2 molecule. so to explore this further we say go ahead and knock out all the kappa b pathway and see what the effect on hcv replication. lo and behold when he did the following experiment, he saw

that knocking out all of the -- lead to increase kappa infection which you would expect because these are innate and -- if you knock it down it would go up. around ikka alpha leads to significant reduction of replication. the reason ikk alpha and other

kappa b components have an imposing factor on hcv propagation. so how could this be. furthermore, i say since i can overexpress ikk alpha that can lead to the phenotype or increase replication. if we knock down the down

stream, if indeed ikk alpha is mediated through this, we shoot see any over expression in ikk alpha. and actually this is not what he saw when he did the following experiment. when he treat the cells with -- against f kappa b one and two,

he still could see the increase by replication as a result of ikk alpha expression. so it suggests that ikk alpha is going through some other pathways to the classical and kappa b pathways. so therefore the effective ikk alpha with complication is

independent in kappa b. there's also a lot of data that went into proving this because we show them that this is indeed a kappa b. i'm not going to you them but you'll read about it in a couple months that this pathway is indeed independent of kappa b.

so what does ikk alpha act in the hcv life cycle. i showed this to you before. various different assays have been developed in the last few years. really look at specific step of the viral life cycle, the hcvpp and the binding assay.

the entry is to the single cycle infection assay to look at the early steps -- looking at translation, replication assay looking at replication and finally the hcv cc assay can look at the complete viral life cycle. so applying these techniques

show that ikk alpha actually act on the assembly process. as we just remind you that the process -- so a what does this mean. pathologically, hcv infection is associated with a pathological hallmark of steatosis. what you see here in the sample

of hcv infected -- this is similar to another disease we see very commonly so-called non-alcoholic fetal hepatitis in which the primary injurious -- the lipid droplet is involved in the hcv infection. this phenomena has been described in various different

cell culture models. hcv infector cells as has been shown to high level lipid droplets was shown here. this is a core staining as you can see that. there's increase lipid droplets and -- well with hcv core protein.

then you treat the cells with ikk alpha, you can see that the lipid droplet was significantly reduced although you can see the core there. but no longer -- with the core of the lipid droplets. this suggests that hcv infection induced lipid droplet formation

and co-localizes with had. cv core. ikk alpha mediates the fact that hcv lipid droplet formation. so to further explore the fact that ikk alpha and lipid droplet formation overexpress wild type ikk fal awe that can increase hcv replication.

over express itself with the ikk alpha -- you can see that in the cells expressing this h wild type alpha you can see significant increase in lipid droplet formation. whereas when you over express the negative dominant mutants, you see actually a decrease in

the lipid droplet formation in the cells expressing this negative dominant ikk alpha. so how does hcv induce the lipid droplet formation? this is a genome virus. it's a ten killer base agent encoding a poly protein here but there are two -- traps later

regions that play a critical role in biotranslation replication furthermore the -- encodes so-called pathogen-associated -- that can be recognized by -- or lead to induction of interferon. this is described by -- many years ago.

to make a long story short was able to show that this was indeed responsible for the induction of lipid droplets, showing you here sustaining ikk alpha and lipid droplets. and when you treat the cell. these are not infected cells as ikk alpha.

you can see the decrease of lipid drop formation. when you treat the cells with hcv10, you can see there was a significant induction of lipid droplets as shown here. and that when you treat the cells hcv10 traryt cells as ikk alpha srna he was able to

aggregate the high induction over lipid droplets. a technique of quantifying lipid droplets eighty again hcv10 was able to significant induce the green color that's representative of the lipid droplet. similarly using a viral mimetic

back in -- function of the molecule was able to induce the production of lipid droplets. so the ikk alpha is involved in lipid droplet biogenesis -- that is mediated by ikk alpha. and this hcv10 is responsible for this effect. so to study further as i

mentioned to you that ikk alpha is activated and showed that in hcv infector cells -- there's no change in the level of ikk furthermore the phosphorylated ikk alpha is distributed into the translocator into the nuclei when you perform vaccination of cytoplasmic to nuclear

experiment and it's just a quantification of the signal. and that's why he saw that. the ikk alpha phosphorylation and localizations. to further explore the local case ikk alpha infector cell frank performed my microscopy -- green represents acd core so hcv

infector cells. as you can see that in the hcv infector cells there seems to be increase red color in the using the software of the -- he was indeed able to see these cells infected hcv, this increase localization actually could quantify by measuring many

of the new fluorescent intessity of these cells to give you statistical and significant increase of localization of ikk alpha in hcv infected cells. so i guess the next question, so what is ikk alpha doing once you go through the nucleus. the answer to this question

frank designed the following experiment, you can have four conditions where one condition would be just you make it a control. and then another condition just treat the cell with -- ikk alpha and the third condition would be control the sirna infected hcv

versus the ikk alpha -- the full condition indeed qpci will demonstrate reduction of ikk alpha silencing and decrease replication and -- infected so when you do the experiment and look at the pathway now low and beloald lacey infected genes up regulated belong to the

metabolism genes. this increase can be reduced by either sirna against ikk alpha represented by the blue color. even in cells that are not infected by hcv, there was a significant reduction of -- in the cells. and then to look specifically at

these micro geneic genes. these are regulators of the lipid metabolism itself. when you quantify the expression of these two genes you saw an increase in the hcv infected cell hat can be blocked specifically by treating the cell with ikk alpha sirna.

so hcv infection induces ikk alpha mediated expression of lipid metabolited gene -- and just to look further i told you hcv10 is a responsible element for hcv. he saw the same thing induction sivp application of this induction for the treatment of

and furthermore when you treat the cell against siebp he was able to replicate the phenotype that replications significant decrease when you silence the expression in cells as shown here. the reason that the hcv10 reduces the expression of --

metabolism genes and the si one and two for hcv propagation. so this is just also show that using the overexpression, you can increase expression but with dominant and negative mutation you can decrease the srebp induction. again going back to primary

human pa at -- hepatocytes,they were significantly able to rules the ipp one and two in the human hepatocyte only with inhibitors against all the ikk but not ikk data specifically inhibitors so therefore we conclude the ikk alpha plays a critical role in the transcriptional regulation

of i -- one and two. to summarize this part of my talk do you know why genome-wide -- in the pathway that have anti-viral effects, ikk alpha has a predominantly proviral effect. it kk alpha plays an important role in the step of the hcv live

hcv infection activates rules the expression of srebp1 and 2. this is the inductions that lead to lipid formation and to serve the hcv assembly. finally hcv exploits the host immune response response and high jacks host lipid metabolism to its advantage.

the identification of novel host has major implications. i showed you the block ikk and if you saw that its phenotype infection is quite dramatic. i'm not supposing to use inhibitor therapy but i think this gives you a lead about what

you could do in the future. so moving on to the micro rna perturbgens with this risk complex specific target and using a silencing translation leading to its degradation. so how about micro rna infection. the there are plenty of examples

of that. first of all many host rna viral began express in life cycle. conversely that some virus especially the dna virus and co-viral micro rna's so-called that will affect the host gene expression. it's a complicated interaction

there with sce -- plays a critical role in hcv replication from the work of peter -- group published in science many years ago. inhibitors of this is actually being developed as anti-hcv therapy in the clinic. several paper illustrated the

concept of that in a recent study published in the new england journal demonstrated efficacy of this approach. other micro rna live cycles regular lag host factor has been identified. these are just some examples. so these are more synthetic rna

so we can take advantage of the so-called mimics or inhibitors as tools to explore biology. transsector cell will mimic that will lead to decreased expression of the target gene whereas when you transect a cell -- so you can imagine this could be adapted -- gain

function or loss function. that's exactly what frank did a library about a thousand micro rna genome wide screen in the same format. he was able to identify micro rna that's important to hcv this is just data that plotted in this called volcanic plot.

to implicate the cut off value. on the x axis it's a change as a result of the micro rna treatment and the y axis is a t value. and the color dotted line which represents the cut off and then the blockout represents the t value of .0025.

with any point following this area considers hits. interestingly enough it came to a positive hit right there. that is the plots of part one and part two inhibitors assay. just point out this is the same slide i showed previously but in the inhibitor assay the micro

rna turns out to be the other side as you expect beit's the inhibitors that will inhibitor bioreplication. this is generated by helen when she put everything together had the micro rna with many different host factors and network format that's

preliminary and many of these host factors actually overlap with srna genome screen. let me end my talk with the probe of perturbagens. this is of the roadmap initiative many years ago using common funds to encourage people to explore biological phenomena

using the technology back then was ngtc available looking at large pool of small molecule libraries. so that's great, we have an interesting assay. i went to our colleague at ngc -- he looked at my assay format and laughed.

he said no your assay format although using -- has automated image. it's not the true format where you're talking about screening against of compounds. you got to really be able to administer it even further. gee that's too bad.

going back to the drawing board and spent time to try to set up or optimize so we can screen the large chemical library that n cat has. so the characteristics of this high throughput assay is simple. you can do staining and these other things you do to knock

around the cell. you got to -- minimal manipulation i said. and these 1536 well plate format. they may contain five microliter of the median. you have a very high signal of ratio.

it has a robust reproducibility. these are narc factors that we look at. you have a triation base approach and then obviously you got to address the whole issue of cytotoxicity when you do a cell base assay. not to bore you with the

details. the set up assay seemed to work and then in collaboration with ncgc we screen about 500,000 compound library. using -- robotics and -- such as looking potency profiling, activity classing, structure clustering.

this is -- this is compound precursor of a protease inhibitor that is in clinical use for hepatitis c found to be great similar with one class of compounds that identifies -- so this is good to know we're picking out something that's very similar to something that's

in the clinic. then we go in this approach we have identified about 600 compounds and we thought maybe we should go through a secondary confirmatory screen. we'll use more dozens and then same format but similar we include the cytotoxic assay

so using this we'll confirm activity in many of them and many of them also were non-cytotoxic. using this approach narrowed down to 200 compounds. it's not too many to work with. so what do we do next. we decide to use a secondary

screen that's solely different from our primary screen. went back to the same format that we use for the stainingor the -- because the number's management 284 -- and then using this we're able to narrow it down compound the high efficacy high mote see low toxicity of

158 compounds for each life cycle assay. going through the whole life cycle assay, we're able to select the compound based on high potency and efficacy --hcv life cycle. and by performing structured bio foe matics.

so with all these assays we are down to five lead compounds -- selected for assay chemistry and further development. going back to my first. so are we at zero date for hepatitis c yet. the question is not yet but we are close.

i never happened the time to share with you all the development or advances in hcv treatment but you heard we'll actually be able to cure about 70% of the people with the newest combination of therapy. just think this was discovered less than 25 years ago.

we can right now, not yet but probably in five years we can actually cure everybody of hepatitis c. i think that's a remarkable journey and it's really, i mean it's one of the things that it's very exciting to be part of this history.

i'm sure dr. alter has a lot to say about that as well. and in light of this actually harvey and i wrote an editorial in annals of internal medicine last year on advancing therapy hepatitis c the end of the beginning and possibly the beginning of the end and really

highlight what's been happening. but certainly toward the end both he and i lament the fact that we're going to be so successful, we're going to be out of a job in a couple years. i think harvey is fine. i need a second career so i better start thinking about

that. finally i wanted to recognize the people who have contributed to the work in my lab. this is a photo of the whole branch. i'm glad to work with all of these wonderful people in the group.

i mentioned some of the names who have been involved in the srna and micro rna screening projects -- and have been involved in the molecular library initiative. i certainly want to acknowledge the people that collaborated with the medical school in the

early part of this study. and finally to the n cast people who have been extremely helpful in moving this project along and is really extremely valuable resource on nih campus. and on that note i'll stop. i think the plan is that we're not going to take any questions

and harvey's going to go ahead and give his lecture and we will answer some questions together at the end. okay. all right. [applause] hepatitis e was first discovered in 1981 and it was another bad

kraut -- outcome of the afghan wars. this was at the time when it was russia fighting in afghanistan exphb huge numbers of russian soldiers were coming down with acute hepatitis. it was an epidemic and it seemed like it was eventitis a virus.

when you actually tested for it, it was not hepatitis a and a russian scientist went back and studied this further. and uncovered the new virus and as part of his work he actually ate some filtrate with this projected virus, came down with a severe case of hepatitis

himself but was able to get samples of serum and stool and everything. and he discovered the hepatitis e virus. so if you want to discover something, infect yourself. thee the lesson today. anyway, this was now the

hepatitis e virus. and it was indeed different from hepatitis a virus not serologically but it had certain clinical features that differed. it had a male predominance, quite striking. tended to happen in older people.

could be equally severe. but hepatitis a was always a self lumen infection and some hint that this might become a chronic infection. there was a higher mortality rate. in this particular study it was in hepatitis a and 6% in

hepatitis e and genotypes three and four which i'll talk about in a moment. there is a mortality rate with hepatitis a in patients but the rate is higher. these were three studies of -- hepatitis, and hev was much more likely to be asymptomatic --

even though it's typically presented, it was found because of acute observable hepatitis when you started the sample large numbers of people you found majority of cases were sublincoln like hepatitis c which is basically a subclinical disease.

so hepatitis a was being masked, hepatitis e was being mask because of the clinical -- hepatitis a. it wasn't until you could rule out a that you could find e. similarly reminded me of the recent discovery of the gene for shyness.

now, this gene would have been discovered much sooner except that it was hiding behind another gene. can't win them all. hepatitis e is a smaller than hepatitis c to killer base non-enveloped single stranded rna virus.

it now has its own classification that's called -- like hepatitis c it's got its own genous. there are four genotype but only one sero type which is important in testing. genotypes one and two are actually human viruses.

they are endemic and epidemic, particularly the far east. geno types three and four are swine viruses that can affect humans. this is a zoo nosis. this is the main goon -- genotype in the u.s. and south america.

in the entity hepatitis e, so you have the virus and you actually have the disease hepatitis e. you can see the far east hepatitis e accounts for a large number, near 50% of acute hepatitis cases. in the middle east, it's still

significant down about 7%, 17%. in egypt, about 22%. but in the u.s. at the time of these maps were made, hepatitis e didn't make up any of the segments. the small segment there is actually non-a to e hepatitis, an unknown entity at present.

cdc has recently summarized all the cases that were since then, they had a hepatitis e testing laboratory, and people around the country who had cases of non-a non-b non-c hepatitis, sent samples to the cdc to see if it might be hepatitis e. indeed 26 out of 154 cases or

17% were hepatitis e infections. and the cdc then studied epidemiologically these cases and found 11 out of 26 were actually travelers who would travel to endemic areas who had geno types one and two prevalent in those areas. but 15 were non-travelers who

had so-called -- infections. the means infections develop where they resided but they weren't imported from outside. you can see the striking difference between those in the travelers versus the non-travelers where the non-travelers were much more

likely to be subclinical and carry infections, occur in the high proportion of cases in people who were immunosuppressed, very few had organ transplants. they were all genotype three and the others were geno types one and two.

some of them they had hepatic failure. so these cases were clearly different than the imported cases. and that really was reflection of the geno types. so genotype one, the epidemic form and basically a waterborne

it occurs in a relatively equal male female ratio whose genotype three is predominantly in males. it's predominantly in older neither one is barely spread to any great degree. the source for genotype one is -- genotype three we'll get into in food.

and agent of genotype one as human agent of genotype three is predominantly a swine agent. and the fatality rates strikingly in genotype one has been described fatality in women who are infected in the third trimester of pregnancy. we're up to 20% died from

whereas genotype three this has not been observed and the deaths are occurring in people that we'll talk about. the extra hepatic manifestations of both genotype one, the pancreas is one of the extra hepatic organs that are involved with genotype three, mostly cns,

different -- syndrome has been described with different radiculopathys. we'll get back to people who are immunosuppressed. so this is a typical course that i borrowed from -- this is characteristic of almost all viral infections.

the first thing you find is a viral nucleic acid hero curing -- in the first line going up. then the disease begins alt elevations shown here in yellow. symptoms if you're going to have them. and then the disappearance of

igm anti-body and the appearance of igg and anti-agv. this would be the same in hepatitis c or hepatitis b. and also the same in hepatitis b and c is that the disease is really an iceberg. what we see is severe acute renal failure or even acute

enteric hepatitis is a small proportion of this iceberg is the visible part but you have a lot of -- hepatitis. you have people who have no hepatitis at all. they just have anti-bodies, zero conversions are very track gent. most of the diseases is

subsurface and that's true with hepatitis c as well. what are the clinical features of atv infections. the incubation period is three to eight weeks. as i said most cases are self limited but now very importantly chronicity is being seen in the

new compromised patients and that chronicity can lead to cirrhosis. in a cruiseship it was the one of these -- it wasn't one of those cruiseships, it was a nice epidemiology i studied because you had a closed population and there was hepatitis e that

occurred on board. it was probably food, food borne in shellfish but it hasn't been proven. but of all the people on this ship who ate that, whatever it was, only 21% became and most of those were elderly men.

so i'm not going on any cruiseships. now in the toxin cases the average age is greater than 60, male greater than female at least three to one. the fatality of course all geno types is about 5%. mentioned the -- hepatitis in

pregnancy. and now the contrary cases of acute -- liver failure that have occurred even in the u.s. and most of these represent acute chronic liver disease we'll get into. dr. somalia is here and she's actually doing a large study of

this acute on chronic liver meaning an acute something added on to a chronic existing liver and it can become very serious. i mentioned the extra hepatic manifestations. interestingly, in china now there is an effective atv vaccine that's gone through

clinical trial involving a million people. only in china could you do that. and it was highly effective. i believe it's beginning to be used in china. it's not licensed in the u.s. nor to we actually need it in the u.s. at this time.

this just shows the male predominance again and the mortality rate across studies. u.s. mortality being very low and ranging from 4 to 10%. so when you are looking for a cause of the liver disease now, you have to look for -- some time.

and atv has become one of the zebras, one of the things you wouldn't typically look for. i show that because i took this picture when in africa and i liked it. i'm giving you a case example of looking for the zebra. here's an elderly man, 79 year

old who developed fatigue and jaundice. had no preexisting history of liver disease, no alcohol use, no other risk factors of viral helptitis. a lot of medical problems. and who was on a lot of medications many of which i have

never even heard of. but importantly all the medication had been taken long term. there wasn't any new drug introduced just before his hepatitis. on exam he was jaundiced and the laboratory showed a bilirubin

very high across the normal being 40. elevated phosphatase. he was tested for hepatitis a, hepatitis b, hepatitis c. they were all negative. tested for anti-nuclear anti-bodies in smooth muscle anti-bodies looking for immune

they were negative. had an ultrasound which was unrevealing. so the first thing you want to do in this sort of situation is assume it might be -- stop all the medications. and lo and behold the patient got better.

the alt level dropped to normal. not to normal but it did eventually get down to normal. and bilirubin came down. it was a drug induced hiptitis. they were looking for zebra at the same time and they tested for anti-hiv and sure enough at the same time that the drugs

were being stopped they found that he had igm and igg anti-atv and atv/rna genotype three. as you follow this patient over the course, the igm disappeared. the igg remained positive and the rna disappeared. a classic case of acute so since all the drugs had been

constant, this was probably the cause of this acute hepatitis. which it's been a paradigm shift now in our thinking about hepatitis e and now i'm beginning to lead into blood transfusion aspects of what the implication of htv are for blood transfusion.

we haven't worried about it. but now it's been this paradigm shift because it was always thought to be an acute self limited disease so that the lack of a donor coming in asymptomatic donor coming in when there was no viremia was unlikely.

i haven't mentioned this yet, it's found the anti-body to atv is found in extraordinarily high prevalence. in the u.s. get back to that. we now know that this can cause a chronic infection. that totally changes the

perception of how serious this disease is. so far only an immunosuppressed patients. particularly the solid organ transplant patients. it's known that not only can it evolve to cirrhosis but it can evolve quite rapidly much more

rapidly than hepatitis c. and in these immunosuppressed patients, it can lead to a chronic carrier state. what we worry about in transfusion is a silent carrier state. we have not yet shown that there is a silent carrier state in

asymptomatic people in the u.s. evidence for this chronic infection or just a little bit more about it is that there has been multiple cases. in liver and kidney transplant recipient in cases of lymphoma, particularly those treated with tuskimab -- almost all these

cases of chronic hepatitis have been represented -- genotype three infections in endemic regions, non-endemic regions. viremia levels tend to five or ten to the seven copies per ml. this is a scary part. this evolution to cirrhosis and up to 50%.

and liver failure and death may ensue from that. so from the transfusion standpoint, immunosuppressed transfusion recipients therefore could be at risk. and many of the patients that we transfuse particularly here at the clinical center are

so i worry about this. now, there's more evidence for this chronic hepatitis. this was a study, a nice study a multicentral review of 85 atv infected recipients in 17 different blood centers. these are organ transplant out of those 85 organ transplant

patients, 56 or 66% had chronic atv infection. 18 of those cleared when they reduced the dose of immunosuppression. so again showing the relationship to 20 of them they treated mostly with interferon.

and 14 of them went into a sustained viral logic response -- two of them died there cirrhosis. so overall, eight out of those 56 patients developed cirrhosis or 14%. back to the acute chronic liver disease, this was defined as

acute liver injury with jaundice and coagulatopathy. the patient previously diagnosed or undiagnosed with liver so you might have a patient with hepatitis c chronic asymptomatic they become jaundice and may go into hepatic failure and encephalopathy.

when you see this pattern you think about super infection with another virus. a c patient getting b or a c patient getting e or b patient getting e or it could be hepatitis b itself sometime reactivates in a very virulent fashion.

it could be a patient you're following and suddenly is imbibing a lot of alcohol. so these things that are healthy can be very bad for your liver or it could be a flare in an autoimmune hepatitis or new onset of immune hepatitis. in that picture you have to

think about hepatitis e now. in bang -- bangladesh theyfound 22 percent were due to hepatitis c virus. it is becoming more complex than ever imagined and a more important disease. it reminded me of the relative complexity of men and women that

i've studied intensely. and it was depicted on this slide where we're just a simple on off switch because women are very very very complexed. so i want to talk now about the epidemiology of hepatitis e and the zoonosis. zoonosis is an animal agent that

has adapted to humans. a lot of that is in the food chain and an important example perhaps is this where a simian immune deficiency virus in primates, in africa got to be eaten by hunters and tribal people and over time mutated and became hiv capable of infecting

man and then spreading from man to man. the same happened with simian t lymphotropic virus where monkeys killed mutant adaptive mutated became human t lymphotropic virus infection. and in the same with simian -- virus infection but hiv was

clearly the most important of these transmissions. but the other really interesting one is this. sheep were infected with a disease called scrapie. because they got itchy. they would scrape against fences.

that was shown to be a pre-on the sheep were then slaughtered and for food but also part of the remains were put into ofal. ofal is a food given to cows. this caused a neurologic disease in cows for bovine -- encephalopathy, another pre-on but the cows would ground often

including their neurologic tissues and put into meat pies and hamburgers, particularly in england and cause variant choice of -- disease the human version of mad cow disease. this was a clear food chain through multiple species. and there was of the disease now

in elk and dear called chronic wasting disease which is another pre-on disease which hasn't yet been proven to transmit demand but could through hunters eating fresh elk and deer meat. lastly the tsars virus, the respiratory virus in china causes epidemic and fear

actually traced to a civic cat. these civic cats were often eaten. i don't know if that's exactly how the virus got into human. it became a respiratory transmitted disease. the things we worry about now that of course are all trouble

now in the blood world are these vector borne diagnosis. so you have west nile virus which is really an infection of birds and sometimes horses. and mosquitoes bite the birds and then by -- bites man andgets infected. man is the end stage of this

disease but the host is really the bird. and the same is true now for deer, deer and mice. they carry ticks. they are a taxi service for ticks. ticks by the man. this is an early disease -- and

all these are blood transmissible. it's been a lot of talk about using pig organs for transplants, pig hearts or pig livers. although i don't know any cases this would certainly scare me that some pig virus would get

into humans. and i could really should not put the pig up here as a food borne source that i'm show you so that's the picture of the zoonosis. why pigs? well the pigs are the host for hev, the primary hosts for hev.

you can show that the rates of antibody to hev are high in blood donors and go often upwith age. anybody who works around pig farm are much more infected. and so how, how is this happening. how is hev and we're not generally eating raw pig meat

but there are some things that may frighten you. and i caution you, this is not for the queasy. but there is this gastro elitism movement right now where people eat wild boar pap deli. there's a whole variety of exotic foods using pigs that are

not always cooked to the ultimate. in france and other parts of france where there's -- which is a tremendous favorite of people where 80% of the people are infected hev. this is basically uncooked pig liver and other parts.

apparently very tastily. they will essentially eat anything, anything except american food. so i found out that pet treats contain pork liver. so have you ever munched on a milk bone. there's liver slime that comes

out of pig poop and it's used to irrigate vegetables in plants. so have you eaten any veggies today. this is conceivably a way that non-meat could be contaminated with pig. also water from pig farm, the irrigation of vegetables.

so wash your vegetables. dunkin' donuts i found sells pork doughnuts in china. scrapple. scrapple, a very popular southern dish is made from pig heads and pig liver and not in necessarily cooked to the went around, cvc went around and

tested raw pig liver in the par markets. your average daily supermarket and 11% of these tested hev/rna positive. so every one of these cooked properly when you get them home. usd says you have to cook pork meat to 145 degrees but organs

are cooked to 160 degrees. i think people who love organs might not like them overcooked. so that's a potential source. basically these are some of the ways but we really don't know how all this hev is getting around. but food is thought to be the

main culprit. so let's get to transfusion now. this was the first case of transfusion transmitted hepatitis, in japan. very nicely studied case where the alt levels are shown in red and the bilirubin levels in yellow.

and you can see that about 18 days after transfusion, the alt went up to 1800. the bilirubin went up to 18 as quite a severe case of jaundice. and they went back and traced the donors to this patient and they found one donor who had been a repeat donor.

on predonations they tested negative for hev donation given here it was positive for hev/rna or negative igm or igg antibody. but five months later sample on the same donor showed the donor now to be hev/rna negative but positive for igm and igg. so this was a nice taste of

evolving hepatitis e in the donor. then transmitted to the recipient and the two had complete sequence identity. they were both genotype four. so this is a nice case. in that same study, they looked at donors who had elevated

transamase levels. they found in six of the 16 who had elevated transamase were rna positive and five or six of those were igm positive. in japan they screened, susan do they screen for alt? i don't know whether these donors would have been able to

donate or not but certainly it shows that hev/rna was in the donor population. here's the first case in england, except a much delayed onset. this was a patient who had lymphoma, was a chemo therapy about 33 to 40 days after the

traps fusion, alt levels went up to 800. i believe went up quite high as well. and during the course of that acute hepatitis atv/rna was present. later on igm was detectable up

to this point igg was not detected in this case. they went back to the donors here found that there was a donor who developed flu-like symptoms, 14 days after that donation. the donor at that time had an alt of over 2000.

and the donor was then igm anti-hgv positive genotype three and the patient was sequence identical with the donor. these are unequivocal cases. they are about six to eight of these cases now. so itv clearly can be a transfusion transmitted disease.

this is a nice study in an endemic area. it's hard to pick up transfusion transmission in endemic area because you don't know if it's coming from the foodor the water. in a recollect speculative study they looked at people who has

been multiply transfused versus those not transfused found that 9% of those multiply transfuse -- preceding three months, they found that they found that 43% had atv/rna compared to 2% who had not been transfused. they did a prospective study of

25 people. small study but they found that those of those 25 were susceptible anti-hev negative prior to transfusion. 13.6% contain hev infected from the sawdust study to the follow up compared to non-in the non-transfused group.

so this is indirect evidence that would suggest transmission. they did trace these cases, these sero conversions in a recipient, they trace it to four donors who are hev positive and igm positive. here at nih bob persell took some of our hard study cases.

these are cases of post transfusion hepatitis back in the late 60's where most of the cases were in retrospect hepatitis b or c. and only one case appeared to be i'm going to skip this slide for we just looked at almost 2000 donors here at nih.

and we found that igg anti-hev amount body was present in 18.8% of our donors. these are healthy volunteer donors. and .4% of them were igm none of them had hev/rna. you see the confidence intervals were pretty small because it was

a large number of donors. so between 17 and 20% are blood donors in america are atv exposed. that's been shown now in other places as well. you can see in the donors there's this nice step wise age distribution.

it's as if this infection keeps accumulating as you keep getting exposed over time. and the cumulative rate is quite high. the key in our study was a perspective evaluation of 362 transfused patients. so in this donor population

where 20% have igg antibody, what's happening to the recipients well we found that only two of these recipients were .5% had apparent atv/agg sero conversus. they were negative pretransfusion and positive post as you get sero samples --

retrospective no atv/rna and no igm. and we concluded there were actually no new infections because one of them had received a high titer ant by. the other one in retrospect probably had an infection beginning in that first sample.

it was negative but it was high negative. and probably infection was started. so that's that. and so we didn't observe any infections. in the upper bound of that zero observations is about .8%.

so very low that we've demonstrated so far. this is that particular patient who you can see had no antibody. these are optical densities on the left. there's no anti-body pretransfusion. 36 the last of our prospective

study samples has a high level of anti-atv. so you say okay, this is an atv infection from the transfusion. but no, if you have the interim samples and if you have the donor samples, you can look at it further. what we found is that there was

no igm or rna in the patient, that the patient actually was continuously transfused, received 17 red cells and platelets. what we found was four days before we got this sample, he received recells from a donor with high titer igg anti-body.

so the ant body we picked up was coming from a donor. at that time he also received an atv/rna positive donor and he might have gotten infected but he died several days later so we couldn't see the outcome of that rna positive. it's very important to, and you

can only do this in a prospectus study for zero conversion. should donors be screened. that's the question we're facing now. it's not a major issue at present but it's something that the fda is considering. susan is here from the fda.

and what i call this the triangle of transfusion testability. what are the thing that make you want to test for a virus. well one, can you demonstrate an asymptomatic viremia. would a donor like you to come with an infection and you don't

know. that's what happened with hepatitis c all the time. is there a clinical disease. i've shown you there is if you're an immunosuppressed recipient. is it a tranfused -- yes, i've shown you there is.

with that information the piece we don't know is here. we don't know if that asymptomatic viremia exists. so would you test or not based on this. we also have guided now what's called the precautionary principle.

this came out of the hiv call the cases of transfusion transmission from hiv. so mamedz came up with this precautionary principle said for situations of scientific uncertainty the possibility of risk should be taken into account even in the absence of

proof to the contrary. our typical way is to wait for evidence-based medicine to say yes we should be doing. but the evidence base often doesn't appear for years and years and meanwhile people can be infected. so the corollary with the

precautionly principle is that measures need to be taken to face potential serious risks even without absolute proof. unless you have proof to the contrary. so that's in the background in making our decision also. so why aren't we doing hev

testing right now? well one, we have no standards. we have no pedigree panels by which to compare assay sensitivity and specificity. if you come up with a test that has high non-specificity, you start to eliminate millions of blood donors.

it's a very dangerous thing before you have good assays. we're not at that stage yet. we're probably going to have to screen for hev rna rather than anti-bodies since anti-bodies are so common. we don't have any hev assays that are currently licensed.

i don't know if any are in the pipeline. this is the key here. we don't know the frequency and the duration of asymptomatic viremia in amino-competent blood this is what's going to drive the risky risk -- risk equation-- frequency of the dose that might

be exceeded in healthy blood and we don't know the frequency of the significant open fections of the amino competent and suppressed patients. we have a good idea that it is significant in suppressed how much is this and how often does it occur and what's the

cost benefit ratio of implementing a test like this. so those are the things that blood banks are dealing with right now. so i'll skip. just to say that this is not unique to blood banking. this is not unique to hev,

rather. there are many agents that we don't currently test for. because they are too prevalent or not prevalent enough or whatever. but basically any agent that has an asymptomatic viremia has a threat to the transfusion

transmitted. it's likely that transmission is highly dependent on the duration of the viremia and the concern is dependent on severity of the so in this case we have varying hev with a have malaria, we have denghy and enencephalitis that we can't test for everything.

we're on the vigilance. this is another one of my african slides. but it's not a unique dilemma for hev. we've conquered all the problems, we've handled mad cow we don't worry about these mad cows so much anymore.

we have measures to prevent we've gotten past bird flu where it caused devastating disease in the flamingo population. these are not real flamingos. so i see no reason why we're not going to be able to handle the sweet little pig things. i think we'll get to this

problem and we will or won't test but we'll know in a couple so in conclusion, i agree with everything i've said. and we can have questions now for both of us. >> the hepatitis virus target liver. >> that's a good question.

because they do go perhaps to other organs but they're very specific to the liver. it's a matter of receptors. the specific group of receptors that the virus needs to convey the organ are present in the >> in addition to the receptor or the entry factor response for

the virus getting in, also factors that liver specific viral -- etcetera. so there are other factors [indiscernible] specific focus. have a queson. where you shoaftd that the -- caused zero conversion in that patient.

you said he died but do we know if liver failure was -- >> no, he died, he was a very sick patient. he had received 72 units of he was in bad shape. it wasn't acute and chronic. >> so is there a move to test, given the difficulties, if an

immunocompromised patient is going to be receiving blood transfusions, is there an effort to select out that group to test the blood that they would be getting? >> that's hard to do. it's hard to have two inventories in the blood bank.

it was done in the past where cmv screen blood only went to immunocompromise patients. but i think if the tests were implemented, it would be done for everybody. but your question raises, if we want to study this further, maybe what we should do is study

immune deficient patients. we're doing that to some extent specifically targeting immunosufficient patients to see if they are converting. >> what about in the middle east and other parts of the world where you showed the data of the ryhigh prevalence of this.

what are they doing? >> i don't think anybody is screening for atv for the blood supply. and the higher the prevalence, the more difficult it is to screen actually s but if you screen for antibody, if you screen for hev/rna, that could

be done but in those areas most of the transmission is coming from water supplies. undeveloped nations and the developed nations and the rate of new infections are low. it's a lot of effort for maybe a small payoff. first to get the standardized

panels and standardized tests because we couldn't do this even if we wanted to right now. and secondly, to really study the asymptomatic viremia better. by the way red cross is testing 10,000 donors to see how many have hev/rna. >> you mentioned there's a

vaccine available in china. can you tell us if it's -- and there is an intent to bring it over to people who are diagnosed to hev here? >> well, the efficacy is very good, about 95% efficacy. and i think in places where hev is very prevalent, this could be

introduced by china, could be introduced as a national policy. but it's not a therapeutic vaccine so you don't want to give it to people already so the need in the developed world is not sufficient right now, i don't think, to introduce that vaccine.

>> what about injection drug users for hev, should they be vaccinated for hev? >> no, i think we should vaccinate the over eaters. >> just one other question. if someone is hiv positive but their disease is under control th art, are they still more

susceptible for hev infection. >> i doubt it. i think it's all the matter of degree of immunosufficiency. >> while i'm walking up here, what do the mitochondria look like in hev where you have lipid droplet accumulation. >> yes.

i mean we haven't really looked at it closely. it's possible that maybe it's there is some data suggests the mitochondria -- not clear how that's involved maybe it has to do with the ox -- oxygen species -- trans. >> in blood transfusions, what

is, let's see, what is known about optimal matching of the donor and the recipient. and the second part to the question is what are the measures of success in blood transfusion? >> well, i mean the matching issues is a different issue than

transmission. i mean we are match donors for many different blood groups. not all and we look for antibody to blood groups from the recipients. but as far as the transmission of the major diseases, hiv, htlv, hbv and hcv, those are now

extremely rare phenomena. hiv, hcv one in two million being at risk for transfusion. the blood supply is really safe for the agents we can test for. so the risks of blood transfusion now are either going to be around the ages we don't yet test for or new agents that

might evolve or thing that have nothing to do with infection. now there's bacterial contamination of blood products, there are all kind of other issues in blood unrelated to infectious disease. but as far as infection, we've come a long way and the blood is

incredibly safe. >> what's the main -- rna positive -- ige positive, what's that mean to protect, the people got protection. >> if you have hev/rna, you are infected at that point. igm is also a sign of recent if you have only igg, it may be

a level of protection but i don't know that. but typically igg alone is protected. not in hepatitis c it isn't though. >> harvey what's the status of treating blood in advance without knowing what agent may

be present. purifying the blood or whatever. >> this is the holy grail of blood trables -- transfusion. one is treatment with uv light and the other is riboflavin with uv lhts. they can get you down to zero copies of that agent.

in europe, much of europe now they are testing platelets. and using one of these two methods to quote purify seems to be effective and seems to have no deleterious effects. the us fda has not yet approved that process in america. but that's where we had like to

head. it just hasn't happened yet. the biggest impedestrianment is red cells because if you add agents to red cells you kill the red cells. you might kill the red cells. riboflavins seem to be safe for >> is there an increased risk or

severity in pregnant women for hepatitis e? >> i don't think so. i think it's only in asia and it's if you are in the last trimester and you actually get the hepatitis at that point. reusceptible, more susceptible to bad outcomes but

not to the infection itself. >> i don't understand that. >> if you're a pregnant woman you're not more likely to get the infection. but if you get the infection you're more likely to have a bad outcome. >> oh, i see.

well listen, do you want to have a last word, anyone. i want to thank you. >>

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