This Month in Blastocystis Research (DEC 2015)

The potential pathogenicity of Blastocystis is something that has kept me preoccupied for more than a decade. Nonetheless, what I find perhaps even more interesting, is the overall role of Blastocystis in both health and disease.

And so, what do I mean by that?

Well, we just published a MiniReview in Journal of Clinical Microbiology (JCM) with the title: "Blastocystis in Health and Disease--Are we Moving from a Clinical to A Public Health Perspective?" I guess we were a bit lucky to get the paper published as a review, since it's probably more likely to be viewed upon as an Opinion paper, and so it would perhaps have been more suitable for a journal such as Trends in Parasitology. However, we would like medical doctors to be aware of our thoughts, and that's one of the reasons why we approached JCM.

Practically all Blastocystis research has focussed on identifying a role for the parasite in disease. Pathogenic properties have been identified for many other intestinal parasites since long; for Blastocystis, however, we still have no rockhard and reproducible evidence of

• Outbreaks
• Virulence-assoicated properties including invasiveness, phagocytosis, or adhesion to other cells
• Symptom relief upon parasite eradication

Meanwhile, no one has really tried to looked into what Blastocystis may tell us about human health. Together with partner labs, our lab has produced data suggesting that Blastocystis carriage is extremely common, and probably also extremely long lasting. We have also shown that the parasite is associated with certain gut microbial communities and that it is more common in healthy individuals than in patients with IBD, IBS, etc. We have even identified intriguing data that suggest that Blastocystis may be less common in obese individuals compared with lean.

These are some of the most important reasons why I think that research into the public health significance of Blastocystis should be supported. We need to know much about what it means physiologically, microbiologically, and immunologically to be colonised, including 'what happens to our intestinal ecosystem when we are exposed to and colonised by Blastocystis?' Can we identify any benefits from colonisation, and if yes, which are these and can this knowledge be exploited with a view to producing drugs/probiotics that mimic any beneficient properties of Blastocystis? What does it mean to become colonised at an early age vs. only later in life?

In this regard, future areas of research could include studies on the ability of Blastocystis to

• induce changes in bacterial communities in vitro and in vivo
• assist in the metabolisation of food items (e.g., short-chain fatty acid metabolism)
• promote stabilisation of gut microbiota
• produce immunomodulatory and/or pro-/antibiotic substances, etc.

Happy New Year everone!

Reference:

Andersen LO & Stensvold CR (2015). Blastocystis in Health and Disease–Are We Moving from a Clinical to a Public Health Perspective? Journal of Clinical Microbiology PMID: 26677249
doi: 10.1128/JCM.02520-15

1st International Blastocystis Symposium - Accommodation Funding!

We are pleased to announce that "Society for General Microbiology" (http://www.sgm.ac.uk/) is going to fund two nights of accommodation for 40 young researchers (below 40 years old) attending the 1st International Blastocystis Symposium (www.blastomeeting2015.com).

Those who apply with a presentation and with no other funding will have priority in application.

Please inform your other colleagues who are interested in Blastocystis research about this important news.

(Please note: Applications should be sent to alfunda[at]yahoo.com)

Looking forward to seeing you in Ankara...

Unstained Blastocystis. Courtesy of Dr Marianne Lebbad.

This Month in Blastocystis Research (OCT 2014) - Trick or Treat Edition

Over the past 30 days I've hardly had any time to focus on Blastocystis. I've been busy preparing for and attending UEGWeek 2014, preparing abstracts for next year's ECCMID conference in Copenhagen, and I've also put a lot of effort into preparing proposals for this round of grant calls from the Danish Council for Independent Research. 

Among other things, we are applying for money to develop DNA-probe based diagnostics, including a unique software, for use in the clinical microbiology lab that entirely circumvents the use of PCR (and thereby amplification bias) and that screens sequence data in real-time. An issue with current state-of-the-art in the area is that no software is available to relevantly and reliably handle the tons of sequence data that next/third/fourth generation sequencing devices are capable of producing. The proposed software will have a vast application range, applicable not only to clinical microbiology but also other areas of microbiology, such as food control, water sanitation, and monitoring of microbes in oil, soil, etc.

We are applying for about 270.000 Euros, and although this doesn't sound like an awful lot of money, competition is extremely fierce for this type of grant (although I'm not sure that the competition has to do exclusively with the scientific and innovative quality of the proposal...). So, let's see if it's going to be trick or treat!

Earlier this month, I was honoured to give a talk in Padova at the XXX National Congress of the Italian Society of Protistology on Blastocystis and its role in health and disease. I also got the chance to listen to some of the remarkable talks delivered by passionate colleagues of the society. There was quite a lot on endosymbionts of protists. The development of mitochondria in eukaryotic cells is a classical example of endosymbiosis; however, there are numerous examples of e.g. bacteria infecting protists, including the parasitic ones. Legionella, for instance, may be found in Acanthamoeba,  known to host a variety of bacterial endosymbionts. Along the same lines, I wish that studies could be made to look up potential endosymbionts in Blastocystis; endosymbionts which may confer disease, and the varying/unstable presence of which might explain the irregularity in symptoms reported by Blastocystis carriers? The question about endosymbionts in Blastocystis is interesting not only from a metabolic and horizontal gene transfer point-of-view, but also in the perspective of Blastocystis potentially serving as a vector, a vehicle for transmission of bacteria and maybe viruses... A nice paper on endosymbiotic associations within protists is available for a free download here. Rickettsia, for instance, are obligate intracellular bacteria found as endosymbionts in different types of eukaryotes, including amoebae, but also in endothelial cells (which are not phagocytic by nature, similar - presumably - to the case of Blastocystis), and some of these rickettsia are  known as causes of spotted fever and typhus. I think that Zierdt is the only one until now who has studied endosymbiosis in Blastocystis...

After the congress in Padova, I got a chance to pay my first visit ever to Venice, which was nothing short of brilliant.

Venice, October 2014.

I did have an hour here and there, however, to look up newest 'releases' on Blastocystis, and I'm just going to highlight a few of them.

Unfortunately in Russian and not available for download on any of the servers that I can access, there's a paper describing the finding of dividing (i.e. alive) forms of Blastocystis in a liver abscess in an immunocompromised woman. The question here is of course, did the parasite end up here by chance (fistula and/or secondary to bacterial invasion?) or by independent invasion? Hope to receive a copy of the paper at some point... and a translation!

There is a paper in a journal called 'Case Reports in Medicine' on what is called a co-infection of Schistosoma and Blastocystis in a 37-year-old male with chronic kidney disease, in whom Blastocystis was speculated to be the cause of chronic IBS-like symptoms. However, there is a number of issues that I would like readers of the paper to focus on: Apparently, the patient had Schistosoma mansoni detected in the urine suggesting schistosomiasis of the bladder. But how was Schistosoma detected? It doesn't say. Was it by microscopy? The patient was ab-positive, but still intestinal schistosomiasis was not ruled out (by e.g. PCR on faecal DNA, microscopy for ova and parasites, rectal biopsy, etc.). The patient responded well to praziquantel treatment and got rid of symptoms, including the intestinal symptoms ascribed to Blastocystis, for which the patient was prescribed metronidazole. We know that Blastocystis is only rarely eradicated by metronidazole alone, and indeed, the article does not provide data on post-treatment stool examination to see whether Blastocystis was still there. I think there is a chance that Blastocystis was an incidental finding and that intestinal symptoms in this case were due to Schistosoma. Given our recent data and improved diagnostic techniques, Blastocystis will more often now than ever become an incidental finding on routine analysis of faecal samples.

There is a paper by Fletcher and colleagues coming out in Journal of Public Health Research studying the prevalence and geographical distribution of enteric protozoan infections in Sydney, Australia, which I haven't had a chance to study in detail. I just want to emphasize that this study found Blastocystis prevalence to be increasing by age, a finding adding support to accumulating data suggesting that Blastocystis is more common in adults than in children, which is interesting from a clinical, epidemiological, and ecological point of view.

Hope to be able to address an interesting and brand new paper on Blastocystis treatment in Faculty of 1000 very soon. 

Happy Halloween!

References:

Fletcher S, Caprarelli G, Merif J, Andresen D, Hal SV, Stark D, & Ellis J (2014). Epidemiology and geographical distribution of enteric protozoan infections in Sydney, Australia. Journal of Public Health Research, 3 (2) PMID: 25343139

Nagel R, Bielefeldt-Ohmann H, & Traub R (2014). Clinical pilot study: efficacy of triple antibiotic therapy in Blastocystis positive irritable bowel syndrome patients. Gut Pathogens, 6 PMID: 25349629

Nowack EC, & Melkonian M (2010). Endosymbiotic associations within protists. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 365 (1541), 699-712 PMID: 20124339

Prodeus TV, Zelia OP, Khlebnikova TA, & Pikul' DA (2014). [Extraenteric infection caused by Blastocystis spp. in a female patient with liver abscess]. Meditsinskaia Parazitologiia i Parazitarnye Bolezni (2), 6-9 PMID: 25296418

Young CR & Yeo FE (In Press). Blastocystis and Schistosomiasis coinfection in a patient with chronic kidney disease. Case Reports in Medicine http://www.hindawi.com/journals/crim/2014/676395/ 

2014 Prospects

Happy New Year!

So, what's in store for us in 2014?

Difficult to say, but as least I can try and say a little about what is going on in our lab. Firstly, we are trying to publish what we are think are very interesting data on how gut bacteria may select for Blastocystis colonisation, a hypothesis we have developed based on studies of metagenomic data.

We are also working with the assembly and annotation of mitochondrial and nuclear genomes in collaboration with our international colleagues; something that will definitely take a while, since we have so few people in our lab to do it (literally one-two persons) but oceans of data (!!) - it's a pity that we cannot speed this up, since genomes are expected to hold keys to some of the great gates of Blastocystis enlightenment. Of course, a constant aim is to attract funding that can help us employ one or more PhD students/post docs interested in genomics and parasites. As always, I encourage my readers to come up with suggestions for funding.

Funding-wise we are also going to try and establish a Marie Curie ITN-network on the roles of intestinal microbial eukaryotes in health and disease and we are also awaiting decisions on other applications; hopefully, we will get some money for gut microbiome and immunological host profiling in experimental animals challenged with Blastocytis cysts. There may also be some work in our lab dealing with the impact of Blastocystis on bacterial communities in in-vitro studies.

Epidemiological data are produced as we speak; luckily, quite a few colleagues in different parts of the world are taking an interest in characterisation of Blastocystis in various cohorts so that we will know more about its epidemiology.

Those are the seminal things. Of course, there will be some exciting conferences, which I've mentioned before, and I'm also looking forward to putting together a Blastocystis review.

Blastocystis Highlights 2013

For decades man has striven to improve sanitation and protect production animals and crops from infectious agents to prevent diseases in humans, animals and plants. We tend to eat highly processed foods and many children grow up in almost sterile surroundings, for instance without contact to animals. Consequently, in developed parts of the world we are much less exposed to microorganisms and helminths than previously, and the extensive use of antibiotics for prevention, treatment and control of microorganisms is well-known.

As we are now starting to get a much deeper understanding of the role of the human microbiome (whatever that is) in health and disease, we become aware that microbes are to a large extent beneficial to us; for instance we are currently realising that human health is more or less proportional to intestinal biodiversity, including colonisation by parasites. I have previously mentioned the intentional use of eggs of the parasite Trichuris suis to alleviate symptoms and maybe even reduce disease processes in inflammatory bowel disease, a disorder seemingly stemming from immunological processes out of balance. Also in the food sector, steps may now be taken to diminish breeding and gene manipulation to increase crop yield; instead manipulation of microbes (e.g endophytes) may be used to makes crops hardier. Using microbes to combat other microbes and disease processes, thereby reducing the use of antibiotics and other chemical compounds will probably - and hopefully - be central to controlling diseases and increasing production yields.

For us in the 'Blasto business' these trends are particularly intriguing. I'm not the only one who just a couple of years ago thought that functional bowel disorders such as irritable bowel syndrome (IBS) to a large extent might be directly attributable to undiagnosed parasite infections (e.g. Blastocystis and Dientamoeba), something that could be supported by data going out from one of the studies that I carried out during my PhD studies. Over the years, however, we and other groups have produced data showing that patients with IBS are in fact significantly less colonised by the microbial eukaryotes Blastocystis and Dientamoeba than the healthy 'background' population (see this blog post). We also have access to metagenomic data that link the presence of these microbial eukaryotes with high bacterial diversity in the intestine, and I have colleagues confirming that patients suffering post infectious IBS-like symptoms do practically not harbour these parasites. Our hypothesis now is that - generally speaking - Blastocystis and Dientamoeba are proxies for high intestinal microbial diversity and thereby for a healthy gut ecology. This does of course not rule out the possibility of pathogenic strains/subtypes/whatever of microbial eukaryotes, and we are currently increasing our efforts to investigate whether these organisms can cause disease directly or indirectly, - I'll post a few lines on some of the work we have in mind for 2014 in my next post. I believe that one of the things that most Blastocystis researchers are interested in currently, is to increase our knowledge on the diversity and biological characteristics of mitochondrial and nuclear genomes.

It takes time to produce, analyse and interpret genomic data on Blastocystis, simply because we have so little money that can be allocated to PhD students and post docs. Although we try hard to get funding, we only have one PhD student working with Blastocystis genome data... I could have wished for at least one more. One year ago, I thought that 2013 would see at least one more Blastocystis genome paper, but so far, only very little data have emerged and only included in conference abstracts. But so far it appears that the genetic universe of Blastocystis is even bigger than most of us may have thought! To get a very preliminary impression of their data and how much ST1 differs from ST7 (currently the only available genome), you may want to visit a previous blog post. This basically means that even though we know about genes present and expressed by one subtype, the situation may be completely different for other subtypes! Very interesting, but it also means that a lot of work remains to get a clear picture of what Blastocystis actually does and is capable of doing.

This year was also the year where three seminal papers came out from London School of Hygiene and Tropical Medicine, all of them first authored by Dr Mohammed Alfellani, who did a magnificent job collecting, culturing and 'DNA extracting' samples from both humans, non-human primates, and other animals from various geographic regions. I have already given numerous examples of his findings. Dr Alfellani identified new subtypes, and did a great job in identifying remarkable variations in the geographical distribution of subtypes in both humans and animals. There are also some useful tables in Alfellani's papers showing overviews of molecular data produced by him and our colleagues. We definitely hope that his papers will stimulate other colleagues to pursuing the epidemiology of Blastocystis and should definitely hold some useful tools for those who are new to Blastocystis epidemiology research. 

I had the pleasure to write up a paper to Trends in Parasitology together with Dr Pauline Scanlan. The paper was free for download in November, and we received quite a lot of positive feedback, so thank you all who are so supportive of the work! It was also very rewarding to put together a review for Advances in Parasitology together with Drs Alfellani, van der Giezen and Clark on 'Recent Developments in Blastocystis Research'.

2013 was also the year where my SSI colleagues and I published a comment in the ISME Journal on how impatiently we are awaiting data on the human 'eukaryotic' microbiome. To map the microbial eukaryotes of the intestine and to try and characterise their structure and function and the intestinal ecology that accompany these organisms are activities that should receive top priority in my opinion. There is a link to the comment here.

Congress-wise, I experienced my first-time-ever Blastocystis session at a conference! It was at the merged meeting arranged by the Scandinavian-Baltic Society for Parasitology and the European Society for Tropical Medicine & International Health. Next year, I will be involved in the session 'Passion for Parasites' at the general ASM 2014 meeting in Boston (morning session,18th of May 2014), where I'll be giving a talk on Blastocystis, and, later next year, I will also be leading a lecture/workshop associated with the ICOPA conference in Mexico on Blastocystis barcoding, - I hope to see a few upcoming Blastocystis geeks there!

I don't think we have ever had better opportunities to do significant research on Blastocystis. More and more people are working with it, our epidemiological data have become a lot stronger, enabling more subtle hypotheses, lots of strains have been sequenced, we have developed protocols for experimental in-vitro and in-vivo studies, so here's to hoping for a vast increase in funding and work in 2014!

Attaching an image of the Nutcracker display currently adorning the facade of the Hotel d'Angleterre in Copenhagen, I wish all of the readers of this blog a Merry Christmas and a Happy New Year!

Literature:

Nicola Jones (2013). Food fuelled with fungi. Nature, 504 DOI: 10.1038/504199a

Dressed Up For The Party But No Invitation...

Here's a bit on the personal side: I'm very thankful to the viewers of this blog! I get quite a lot of encouragement from readers and also good suggestions for future blog posts, which is immensely inspiring and helps me to keep up spiritis at times when things are not going my way... like just now: Funding for Blastocystis research is really, - and I mean REALLY difficult to obtain. Lately, I was microns away from notching a €1.34M grant for research in Blastocystis genomics/transcriptomics/phylogenetics/epidemiology - we had the scene all set with great track record and expertise, potential PhD candidates, superb partners and perfect lab infrastructure; I was one of the few runner-ups, but, alas - no luck! Never been so close to something that big and feeling terribly gutted... Well, next up is the EU (again). Also, we're trying to look into the possibility of world experts joining forces, but to find 100% relevant calls for this is extremely challenging. And if the call is not 100% relevant, applying for funding is a complete waste of time...