Archive for March, 2013

Scientists Built a Fake Virus Shell to Make a Sterile, Zombified Vaccine

31 March, 2013

See on Scoop.itVirology News

Vaccines beef up your immune system by giving it a little taste of a weak—or dead—version of diseases. Now researchers in the UK have developed an alternative approach:

Ed Rybicki‘s insight:

There’s a new one: zombified virus!!  So basically, just virus-like particles – like the Hepatitis B virus vaccine that’s been on sale for years, and the Human papillomavirus vaccines that have been blockbusting the industry in the last couple.

 

And not new, either: others have previously tried the same approach – in plants, no less – and been successful.  But they were from Argentina.

See on gizmodo.com

INFLUENZA, CANINE – USA

26 March, 2013

See on Scoop.itVirology News

Outbreaks of canine flu in other states have prompted some veterinarians to encourage New Hampshire pet owners to consider a flu vaccine for their dogs. If you’re a pet owner, you may want to consider a flu shot for another member of the family: your dog.

Canine influenza outbreaks have been reported in Vermont and Massachusetts. And Dr. David Stowe, president of the New Hampshire Veterinary Medical Association, predicts it’s “only a matter of time” before an outbreak happens here.

The danger is that dogs here have no immunity to the new H3N8 virus, according to veterinarians. And that’s why some are recommending flu shots for animals that go to day care, boarding, grooming, dog parks and other locations where dogs congregate.

“Dogs have never had influenza before,” explained Stowe, a veterinarian with VCA Lakes Region Veterinary Hospital in Laconia, who recently treated a young dog for what he believes was the flu. “It makes it more likely that they may catch it if they’re exposed to it.”

ProMED-mail

Ed Rybicki‘s insight:

We do all sorts of flu here…looks like a useful niche market!

See on www.promedmail.org

Protein structure using viruses and ice

25 March, 2013

See on Scoop.itVirology News

Protein production: Going viral [Via Eureka! Science News – Popular science news] A research team of scientists from EMBL Grenoble and the IGBMC in Strasbourg, France, have, for the first time, des…

Ed Rybicki‘s insight:

Putting viruses to work!  Love it.

See on amanwithaphd.wordpress.com

Synthetic farm virus built in lab

25 March, 2013

See on Scoop.itVirology News

An artificial version of the Schmallenberg virus has been made by scientists in Scotland as part of research to find out more about the livestock disease.

Ed Rybicki‘s insight:

I love misinformative headlines – and the sub-editors who write them [NOT!!].  Do they mean "virus of synthetic farms"?  "Synthetic virus infecting farms"?

 

What they ACTUALLY mean here is that folk in Scotland have used a reverse genetics approach (=made an infectious clone, by expressing genomic RNA from a cDNA in the presence of appropriate viral proteins co-expressed form another DNA) to make infectious Schmallenberg virus, which causes abortion in sheep, among other things.

 

Now it is interesting that, although these guys claim to have made a MORE virulent form of the virus in mice, that there is no outcry, along the lines of the H5N1 saga of recent times.  And possibly there should be, because no-one knows what happens to the host range if you passage the virus in mice, not to mention transmissibility.

See on www.bbc.co.uk

Maize streak virus revisited: 25 years on

20 March, 2013
Maize streak virus: photo from 1978

Maize streak virus: photo by Robert G Milne in Cape Town from 1978

Twenty-five years ago, I wrote a brash, naïve little piece entitled “Maize streak virus virus: an African pathogen come home?” for the South African Journal of Science, laying claim to a virus that we had just started working on – Maize streak virus (MSV) – on the basis that it had first been described from this country in 1901, that it was endemic here, and that it still caused major crop losses.  I did this because research on this and related viruses seemed to have moved almost completely offshore, to Europe and the USA, and

“…the most interesting of the viruses that grow all around us have already been whisked away to foreign laboratories; [that] there they have been cloned, sequenced, and had their most intimate details exposed, far from their native shores”. [Yes, I really did write like that back then].

I asked at that time, if we should

“…perhaps be content to supply foreigners with the (pathogenic) fruits of our fields, and to marvel when the answers come filtering back from abroad?”.

I answered myself by saying that

“…prospects for worthwhile research on African geminiviruses, and on any other indigenous pathogens, are at least as good here as anywhere else.  Our facilities are the equal of those abroad, the necessary expertise is certainly not lacking, and the viruses are on our doorstep.”

I’m a little shocked now that I could have said that then: the paper quotes only three pieces of work from our lab, one of them a Masters dissertation and two papers done by my erstwhile supervisors; we had not yet sequenced any virus, let alone a geminivirus, and all we had was brashness and hope.  Indeed, I went on to say the following:

“We are, incidentally, the only research group with access to molecular biological techniques which is actually working on the virus in its natural environment: this is very useful, as with the virus in all its forms and its vector(s) literally on our doorstep, we can rapidly accumulate, identify and characterize distinct isolates for study here or elsewhere.  We hope there will be a little more of the ‘here’, and a little less of the ‘elsewhere’, from now on”.

I outlined what it was that we ambitiously wanted to do – seeing as we had no money, and only one PhD student at the time – as follows:

“…we now have distinctly different genomic maps of three isolates [!] which differ in serology and symptom expression; we have cloned genomic DNA of several more isolates, and can potentially clone and [restriction] map many more.  With this type of work now solidly established, we intend to investigate other biological variants of MSV – and other native cereal geminiviruses – in maize, cereal grains and other members of the Gramineae.  The aim is to explore the genetic diversity of naturally occurring types of MSV and related viruses, and to identify any isolates that appear unusual in terms of symptom expression, serology or transmission.  These would be interesting to map, and potentially useful in recombinational analyses for the fine mapping of determinants of pathogenicity and host range.” [see later]

The article obviously sank without trace: I can find only three citations to it; two of them mine, and the third from a South African maize breeder.  How the overseas labs that I compared us to must have sniggered…actually, I doubt that happened at all; I am sure none of them ever read it!  In retrospect, we really were regarded as a backwater, and as wannabe geminivirologists; I had at least one collaboration request rebuffed with “we don’t feel our work would be advanced by working with you”, and was told “we’re already working on that, so you shouldn’t bother” for a couple of other proposals.

My hubris was not entirely misplaced, however: we did in fact go on to develop into a world-leading MSV and geminivirus molecular virology laboratory; it just took another fifteen years or so!

So where are we, twenty-five years on from my cheeky article?  Much water has flowed under several bridges; I expanded from molecular virology in the 1990s into plant and vaccine biotechnology in the 2000s, while keeping a geminivirus research group going – and we have published and co-published something like 55 peer-reviewed journal articles and several encyclopaedia and book chapters on MSV and other “African streak viruses” alone, let alone another 14 or so articles on other geminiviruses, with some 1200 citations.  We have papers on geminivirus mapping and sequencing, virus diversity, biogeographical variation, quantitation of symptoms, molecular determinants of pathogenicity, recombination, engineering maize for resistance, the use of two of the viruses as gene expression vectors – and cover pictures for Plant Biotechnology Journal and Journal of Virology.

Cover Illustration: J Virol, October 2011, volume 85, issue 20

Cover Illustration: J Virol, October 2011, volume 85, issue 20

I started with one Honours student in 1986, who went on to do a Masters in 1988; we moved on to having one PhD student in the late 1980s to up four PhD students simultaneously in the mid- to late 1990s, and a postdoc at the same time.  The projects went from simple diversity studies of a few viruses using restriction mapping, through the application of PCR, to partial genome sequencing and studying the molecular biology of infectious clones of the viruses, with a very profitable sideline in phylogenetic analyses; we also moved – with Professor Jennifer Thomson – into a parallel track of plant biotechnology, aimed at engineering resistance to MSV in maize.  We added another track early this century, working on similar ssDNA circoviruses of parrots, using all of the expertise we had accumulated on geminiviruses.  We truly work on “circomics” now – the study of small circular genomes – with its subsets “geminiviromics” and “circoviromics”, with a library of literally hundreds of sequenced MSVs and distinct grass mastreviruses and BFDVs.

Geminivirus particle: characteristic doubled icosahedron containing a single ssDNA

Geminivirus particle: courtesy of Russell Kightley Media

The geminiviromics group has pretty much got away from me now; the folk I trained as PhD students in the late 1990s and early 2000s were enthused enough with the field that they have gradually usurped my leadership and supervisory role, and made the field their own.  I still maintain an interest in using Bean yellow dwarf mastrevirus (BeYDV) as an expression vector for “biofarming” purposes; I am also maintaining a project on Beak and feather disease circovirus (BFDV) diversity and plant-made vaccines.  I think we pretty much did what we set out to do – including the brave prediction I made about host range and pathogenicity, which led to some very interesting work on recombination and genome modularity, and the successful engineering of pathogen-derived resistance to MSV.

So I owe some thanks, in retrospect: first, to Barbara von Wechmar, who sparked the interest – and provided isolates, leafhoppers, and expertise.  Second, to Bev Clarke and Fiona Tanzer (aka Hughes), who were brave enough to blaze the trail, and clone our first MSVs – and make one infectious, in the case of Fiona.  Thanks to Wendelin “Popeye” Schnippenkoetter, for your single-minded perseverance in mixing and matching genomes; thanks Kenneth Palmer, for showing the way for transient expression assays in maize cells and engineering MSV as a vector.  Thanks Janet Willment, for mapping replication origins in MSV and expanding us into wheat viruses; thanks Jennifer Thomson for the collaboration, and Fiona and Tichaona Mangwende and Dionne Shepherd for breaking us into maize resistance engineering.  Thanks Christine Rey for the collaboration, and Leigh Berrie for your quiet competence in our detour into South African cassava mosaic virus.  Thanks Darrin (aka Darren) Martin and Eric van der Walt, for so brilliantly exploring MSV diversity, evolution and recombination – and Darrin for endless amusement in the lab, as well as for two completely distinct and invaluable software packages, for symptom quantitation and recombination analysis.  In the present generation, thanks to Suhail Rafudeen and our student Rizwan Syed (and Dionne and Darrin as supernumerary supervisors); thanks Aderito Monjane for doing such a ridiculous amount of work for a superlative PhD; thanks Dionne and Marian, for keeping the maize engineering afloat – and thanks also to Arvind Varsani, for retraining himself from a papillomavaccinologist to a circomicist, and for popping up everywhere.

PLOS Pathogens: Environmental Predictors of Seasonal Influenza Epidemics across Temperate and Tropical Climates

18 March, 2013

See on Scoop.itVirology News

Human influenza infections exhibit a strong seasonal cycle in temperate regions. Recent laboratory and epidemiological evidence suggests that low specific humidity conditions facilitate the airborne survival and transmission of the influenza virus in temperate regions, resulting in annual winter epidemics. However, this relationship is unlikely to account for the epidemiology of influenza in tropical and subtropical regions where epidemics often occur during the rainy season or transmit year-round without a well-defined season. We assessed the role of specific humidity and other local climatic variables on influenza virus seasonality by modeling epidemiological and climatic information from 78 study sites sampled globally. We substantiated that there are two types of environmental conditions associated with seasonal influenza epidemics: “cold-dry” and “humid-rainy”. For sites where monthly average specific humidity or temperature decreases below thresholds of approximately 11–12 g/kg and 18–21°C during the year, influenza activity peaks during the cold-dry season (i.e., winter) when specific humidity and temperature are at minimal levels. For sites where specific humidity and temperature do not decrease below these thresholds, seasonal influenza activity is more likely to peak in months when average precipitation totals are maximal and greater than 150 mm per month. These findings provide a simple climate-based model rooted in empirical data that accounts for the diversity of seasonal influenza patterns observed across temperate, subtropical and tropical climates.

Ed Rybicki‘s insight:

This is really quite a big deal: I blogged recently on the first paper that explored this notion in detail; here we see that paper vindicated, and new data presented.

 

It is interesting that the virus should have evolved to be spread in this way: in drier cold air in temperate climates, and in warm wet air in more tropical climes.  It also very nicely explains seasonality in influenza transmission.

 

Now, let’s do something ABOUT it!

See on www.plospathogens.org

14 adults ‘cured’ of killer HIV virus [NOT!!]

16 March, 2013

See on Scoop.itVirology News

TWO weeks after doctors rid a baby of the disease, it appears the treatment has worked on full-grown men and women

Ed Rybicki‘s insight:

You have to hate sub-editors – the people who are tasked, in papers like the Sun, to come up with the most lurid headline possible.

 

The facts are these: a number of people were treated, soon after infection with HIV-1, with a course of combo ARVs.  For one reason or another, they stopped taking them – and they are, up to seven years out – controlling their virus load to undetectable levels.

 

Note: they are almost certainly NOT cured; the virus is integrated into their CD4+ T-cells, and is simply quiescent or ticking over at a very low level of expression.

 

Howevr, it is potentially good news – IF it can be replicated in a wider cohort, and IF people can be caught at an early stage of infection.

See on www.thesun.co.uk

A novel coronavirus capable of lethal human infections

3 March, 2013

See on Scoop.itIIDMM News

In September 2012, a novel coronavirus was isolated from a patient in Saudi Arabia who had died of an acute respiratory illness and renal failure.The clinical presentation was reminiscent of the outbreak caused by the SARS-coronavirus (SARS-CoV) exactly ten years ago that resulted in over 8000 cases. Sequence analysis of the new virus revealed that it was indeed a member of the same genus as SARS-CoV. By mid-February 2013, 12 laboratory-confirmed cases had been reported with 6 fatalities. The first 9 cases were in individuals resident in the Middle East, while the most recent 3 cases were in family members resident in the UK. The index case in the UK family cluster had travel history to Pakistan and Saudi Arabia. Although the current evidence suggests that this virus is not highly transmissible among humans, there is a real danger that it may spread to other parts of the world. Here, a brief review of the events is provided to summarize the rapidly emerging picture of this new virus.

Coronavirus graphic courtesy of Russell Kightley Media

Ed Rybicki‘s insight:

It is truly amazing how fast things can be done these days: it was only in SEPTEMBER that the new virus was isolated; the latest fatality was literally in the last couple of weeks.  It remains to be seen whether or not it will spread – given its apparent lethality, we can only hope it does not!

See on www.virologyj.com

Key TB vaccine trial fails; more waiting in the wings – Reuters

1 March, 2013

See on Scoop.itVirology News

NPR (blog) Key TB vaccine trial fails; more waiting in the wings Reuters CHICAGO (Reuters) – A highly anticipated study of the first new tuberculosis vaccine in 90 years showed it offered no added benefit over the current vaccine …

Ed Rybicki‘s insight:

And that’s the way it SHOULD be: a whole pipeline of stuff waiting to go into people.

Unlike the South African HIV vaccine development effort….

See on www.reuters.com

Influenza animation – flu virus mechanism

1 March, 2013

See on Scoop.itVirology News

Animation of the mechanism of an influenza virus and how Crucell’s antibodies target the HA1 proteins on the virus and prevent further spread of influenza. C…

Ed Rybicki‘s insight:

I am sure I’ve done this or similar before – and this one’s an advert for Crucell’s MAbs.

But never mind!  It’s a SUPERB animation, showing things as accurately as anyone could wish for – complete with proteins moving around in membranes and being flexible.  An excellent way of getting over to students exactly how viruses get into cells.

See on www.youtube.com


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