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Entries in Medicine (55)

Thursday
Jun232016

Journal club: Transmissible cancer may not be so rare

Cancer is a disease of our own cells gone wrong. Normally our cells work in harmony with each other, taking cues from each other as to when to proliferate, when to differentiate and when to die. In cancer, mutation takes away this level of regulation, leaving a "selfish cell" that ignores all of these signals and proliferates uncontrollably, even to the point of killing the host.

There have been a handful of rare cases where cancers can actually physically cross-over from one individual to another, such that the second individual is actually growing cancer cells that are not self, but are fully derived from the original host. This has been seen in a few human cases as well as well-described transmissible cancers in Tasmanian Devils and dogs. There was even a recent case study that suggests a tapeworm cancer crossed over into the host. In general, however, it is thought that this type of event is going to be exceptionally rare. Even ignoring the protective effect of our immune system killing foreign cells, it is not like cells from one individual can just float through the air to colonise another. Except, of course, under the water.

A paper just published in Nature looks for transmissible cancers in mussels and clams and finds three examples of cancer cells from one individual clam or mussels infecting and growing in other indiviudals of the same, or even different, species. With high population densities and water flow acting to directly transfer cancer cells, it is probably that transmissible cancers are actually a common feature in many marine environments.

Nature 2016, in press. Widespread transmission of independent cancer lineages within multiple bivalve species. Metzger, Villalba, Carballal, Iglesias, Sherry, Reinisch, Muttray, Baldwin, Goff.

Wednesday
May112016

New insights into Multiple Sclerosis treatments

Multiple Sclerosis is the most common neurodegenerative disease of young adults, affecting 2.3 million people. MS is insidious. It can lie dormant for years, controlled well by treatment, but there is no cure and patients always live with the threat of another attack that takes away more of their function. One of the frustrating aspects of MS is that we have treatments, but we don't really understand them. There are plenty of drugs that work to control MS, but it is impossible to predict which drug will work well for which patient, or how long that drug will work. We don't even really understand the way that the different drugs function - essentially, it is a guessing game to find which treatment will work best in which patient; a guessing game that dangerously chews up time as the disease progresses.

In a major new study just released, the Translational Immunology laboratory teamed up with the Neuroimmunology laboratory (led by Prof An Goris) and performed the first large-scale in-depth immunological analysis of multiple MS treatments. We profiled the immune systems of 245 individuals, including untreated MS patients and MS patients being treated with four standard treatments - interferon-beta, glatiramer acetate, natalizumab, or fingolimod. Since all the treatments are effective in at least some patients, we had expected to find that each treatment ould have a similar impact on the immune system. Instead, the results were surprising - each of the treatments did something different to the immune system. 

In fact, the only common response we found to MS treatment was an increase in the serum cytokine BAFF. The confusing part is that BAFF was thought to be detrimental during MS - several mouse trials found that increased BAFF drives more severe disease, while inhibiting BAFF cured disease. These mouse results were strong enough that two clinical trials had started injecting anti-BAFF antibodies into MS patients in the hope of stopping disease progress. And yet, we found that BAFF was going up in patients that were given multiple different effective MS treatments! Our model suggests that increased BAFF may actually be a protective part of MS treatment, so is it wise to give MS patients anti-BAFF? Unfortunately, our model appears to be correct, as the two trials of BAFF in MS have now been prematurally stopped, due to excessive adverse events.

There are three major lessons to be learned from our study:

First, we should look at testing drugs that increase BAFF rather than decreasing BAFF. This may be a promising avenue for treating MS in patients that do not respond to existing drugs.

Second, we should stop assuming that we understand how existing drugs work. Every drug that we give has multiple impacts on the body, and we should not assume that we know which of these impacts are the protective ones. By identifying which particular impacts are shared across multiple effective drugs, then we are more likely to be looking at the protective effects. If our study had been performed earlier, then I doubt anyone would have gone ahead and given anti-BAFF antibodies to MS patients, and these adverse events could have been avoided.

Third, further large-scale immune analyses such as ours may allow us to predict which patients will respond to which drugs best. In MS this is critical - time spent on an ineffective drug means function is lost that will not be regained - patients need the right drug as soon as possible.

 

You can read more about our study at Neurology: Neuroimmunology & Neuroinflammation:

Dooley*, Pauwels*, Franckaert, Smets, Garcia-Perez, Hilven, Danso-Abeam, Terbeek, Nguyen, De Muynck, Decallonne, Dubois, Liston* and Goris*. 'Immunologic profiles of multiple sclerosis treatments reveal shared early B cell alterations'. 2016 vol. 3 no. 4 e240

Thursday
Apr212016

Flemish scientists find cure for rare immune disease

From Flanders Today:

A long wait

It may have taken them a decade, but researchers at the University of Leuven (KU Leuven) have finally determined the cause of a mysterious disease that has plagued one West Flemish family for three generations.

The disease – known as PAAND – causes severe skin lesions, muscle pain and general exhaustion. It first came to light about 10 years ago, when paediatric rheumatologist Carine Wouters (pictured right) was confronted with the case of a 13-year-old boy who was brought to the emergency department at Leuven University Hospital.

“Because of a cardiac muscle infection, the boy suffered from heart problems, but we quickly realised that the condition was part of a broader auto-inflammatory disease,” says Wouters.

To her amazement, the doctor soon discovered that other members of the young patient’s family were exhibiting similar symptoms. “But the cause remained unknown,” she says.

Unbearable pain

The boy’s father, who prefers to remain anonymous, has suffered from the same mysterious disease for most of his life. “Since I was five, I have had severe muscle pains, and I’ve suffered from extreme exhaustion,” he says. “Sometimes, I couldn’t even stand up and had to stay home from school for days, just to recover.”

He eventually finished school and found a job, but the condition made his career as a truck driver no less difficult. “The older I got, the more frequently I had to pull over to the side of the road and rest for a few hours,” he says.

The pain was so unbearable, he often couldn’t sleep through the night. As more health problems accumulated, the now 50-year-old man was forced to quit his job.

Sometimes, I couldn’t even stand up and had to stay from school for days, just to recover

- PAAND PATIENT
The disease also causes fever sensations and – most visibly –skin lesions. While the former truck driver has sores on his back, one of his brothers suffers from skin lesions on his face, some of which take the form of open wounds, as if the skin had been burned. During cold weather, the symptoms generally get worse.

Altogether, 12 members from three generations of the West Flemish family are afflicted with the disease. Until now, doctors could only ease their suffering with anti-inflammatory drugs and painkillers.

Genetic mutation

The breakthrough discovery of PAAND is the result of an extensive DNA comparison between the patients’ blood and that of their family members who are not affected by the disease.

The study was led by KU Leuven professor Adrian Liston, who also works at Flanders’ life sciences research institute VIB. Liston’s team collaborated with scientists from the Walter and Eliza Hall Institute in Melbourne, Australia.

The researchers traced the cause to a mutation of a gene known as MEFV. They determined that the mutation tricks the body into responding to a bacterial skin infection, even if there isn’t one. The response causes the skin to produce an inflammatory protein called interleukin-1 beta, which causes skin lesions, fevers and pain.

“If you have the flu, the fever and exhaustion you experience are the result of your immune system putting a lot of energy into battling the infection and not having enough energy left to allow you to function normally,” Liston explains.

With PAAND, he continues, “the immune system diverts much of that energy into fighting an infection that isn’t actually there, with disastrous consequences”.

Only one of the parents needs to carry the mutation for the disease to affect their children, though it isn’t necessarily passed on to every child.

The cure

“These insights were made possible because DNA analysis has become more innovative and affordable,” explains Liston. “We also couldn’t have done it without the collaboration with our colleagues abroad.”

Once they understood how the disease operates, the scientists started looking for a treatment. They found it in a drug called anakinra, also known under the brand name Kineret. While the drug is used in treating rheumatoid arthritis, Liston found it also has the ability to block the protein that causes PAAND.

We hope that the discovery will improve the quality of life for many other people in Flanders and abroad

- DR CARINE WOUTERS
In partnership with the University of Leeds in the UK, the drug was tested on a British patient who was diagnosed with PAAND. The results were striking; the patient’s skin lesions cleared rapidly, and the fevers and pain stopped entirely.

 

The medication is now being tested on five members of the family from West Flanders, including the father. “I hope the drug can make our lives more normal,” he says.

For the time being, his son is recovering from a second heart transplant and cannot take the medication. The scientists are planning to involve him and other patients at a later stage.

Dr Wouters, who has stood by the Flemish family over the past 10 years, is happy that their resilience has finally been rewarded. “We hope that the discovery will improve the quality of life for many other people in Flanders and abroad,” she says. Doctors in France and Lebanon have already indicated that they also have patients with PAAND.

The next steps

The treatment was first carried out in the UK because the country’s health-care system reimburses the drug anakinra. For the tests on Flemish patients, KU Leuven researchers negotiated directly with the drug’s manufacturer, the Swedish company Orphan Biovitrum.

We know about 6,000 rare diseases, and more innovative techniques could help us to identify new ones

- DR CARINE WOUTERS
To finance the project, Wouters and Liston used money from a research fund they set up in 2015 to finance the diagnosis and treatment of immune disorders in children, most of which are so rare, they are not covered by health insurance. According to the European categorisation of rare disorders, PAAND affects less than one in 2,000 people.

 

The two scientists have called on Belgium’s federal health minister Maggie De Block to focus more attention on diseases like PAAND. “Rare diseases are not rare,” Wouters says. “We know some 6,000 of them, and more innovative techniques could help us to identify new ones.”

According to Liston, more newborn babies should also be screened for immune system deficiencies. This, he says, could help prevent medical conditions later in life, which “not only affect the person’s overall health, but result in high costs to the social security system”.

Sunday
Apr032016

PAAND in the news

The write-ups range from the International Business Times to Nature Middle East to Science!

Thursday
Mar312016

Decennia-oude, mysterieuze ziekte geïdentificeerd en mogelijke behandeling gevonden

Een mysterieuze ontstekingsziekte teistert al drie generaties lang een Vlaamse familie met ernstige huidletsels, koorts, pijn en uitputting. De ziekte, waarvoor men tot nu toe geen oorzaak of behandeling had gevonden, is nu geïdentificeerd als pyrine-geassocieerde auto-inflammatie met neutrofiele dermatose (Pyrin Associated Autoinflammation with Neutrophilic Dermatosis, afgekort PAAND), en werd ook vastgesteld bij families in Engeland en Frankrijk. In een nieuw onderzoek hebben Adrian Liston (VIB/KU Leuven) en Carine Wouters (UZ Leuven/KU Leuven) de genetische mutatie ontdekt die de ziekte veroorzaakt, en ook een doeltreffende behandeling gevonden. Hun onderzoek werd gepubliceerd in het internationale wetenschappelijke tijdschrift Science Translational Medicine.

Al decennia lang kampen families in België, Engeland en Frankrijk met een mysterieuze ziekte die huidletsels, koorts, pijn en uitputting veroorzaakt. Elke generatie krijgt de helft van de kinderen van personen die de ziekte hebben, dezelfde symptomen. Artsen waren er niet in geslaagd de ziekte te identificeren of een doeltreffende behandeling te vinden. Nu is de identificatie eindelijk een feit en is dankzij een internationaal onderzoeksteam ook een behandeling gevonden. 

Prof. Adrian Liston (VIB/KU Leuven, hoofd van het wetenschappelijk onderzoeksteam): “Dankzij het nauwgezette werk van de artsen weten we nu dat we te maken hebben met een erfelijke aandoening. Dankzij de vooruitgang in de DNA-sequentietechnologie konden we het genoom van deze patiënten bepalen en de mutatie opsporen die de ziekte veroorzaakt.”

Het gaat om een mutatie in het MEFV-gen. Mensen die van hun beide ouders een MEFV-gen met een mutatie overgeërfd hebben, lijden aan de ontstekingsziekte familiaire mediterrane koorts (FMF), een ontstekingsziekte. Bij PAAND-patiënten gaat het echter om een andere mutatie in het MEFV-gen én is één enkele kopie van de mutatie voldoende om de ziekte door te geven. Dit betekent dat de helft van de kinderen van de patiënten de ziekte overerven, in tegenstelling tot de mutaties die FMF veroorzaken (die vaak een generatie overslaan). De PAAND-mutatie zorgt ervoor dat het lichaam reageert alsof er een bacteriële huidinfectie plaatsvindt. Daardoor gaat de huid het ontstekingseiwit interleukin-1β produceren, dat huidletsels, koorts en pijn veroorzaakt. 

Een behandeling voor de nieuwe ziekte?
Dankzij het opsporen van de biologische oorzaak van deze ziekte kon men ook een nieuwe behandeling bepalen. De onderzoekers hergebruikten anakinra (Kineret ®), een middel tegen artritis dat zich richt tegen interleukin-1β, dat ook bij PAAND een belangrijke rol speelt. De resultaten bij een eerste patiënt, uit een Engels gezin, waren opvallend positief. De huidletsels verdwenen snel en de patiënt herstelde helemaal van de koorts en de pijn. Op dit moment wordt een uitgebreidere test uitgevoerd bij Vlaamse patiënten, om te zien of deze gerichte behandeling tot een volledige genezing kan leiden.

Prof. Carine Wouters (KU Leuven/UZ Leuven, hoofd van het klinische onderzoeksteam): “Dit is het resultaat van een intense samenwerking tussen artsen en wetenschappers die al bijna tien jaar de ziekte trachten te begrijpen. Ik ben verheugd vast te stellen dat we deze zeldzame mutatie nu beter begrijpen en dat we voor deze patiënten de weg hebben geopend naar een doeltreffende therapie.”

Citaat van een patiënt: “We zijn blij en heel dankbaar dat de artsen en wetenschappers hun zoektocht naar de oorzaak van de ziekte die onze familie al zo lang treft, nooit hebben gestaakt. We hopen dat de nieuwe behandeling gunstig zal zijn voor onze familie. En we beseffen ook dat de bevindingen andere patiënten zullen helpen om een correcte diagnose en behandeling te krijgen.”

Prof. Adrian Liston (VIB/KU Leuven, hoofd van het wetenschappelijk onderzoeksteam): “Dit is een uitzonderlijke periode voor het onderzoek rond erfelijke aandoeningen. We helderen elke maand klinische gevallen op die enkele jaren geleden nog niet op te lossen waren. We ontdekken nieuwe mutaties en beschrijven nieuwe ziektebeelden en ziektemechanismen waarvoor ook nieuwe werkzame geneesmiddelen kunnen worden voorgeschreven. Patiënten komen daardoor soms in moeilijke situaties terecht, waarbij de wetenschap een oplossing kan bieden, maar de ziekteverzekeringen de kosten voor geavanceerde diagnosetests of nieuwe behandelingen nog niet kunnen terugbetalen. Dit vormt dan ook een uitdaging voor zowel de farmaceutische industrie als de overheid. Zowel nieuwe medicijnen als bestaande medicijnen voor nieuwe indicaties dienen ter beschikking worden gesteld van patiënten die – op basis van genetische testen – zeer goed kunnen gedefinieerd worden. 

Prof. Carine Wouters en prof. Adrian Liston hebben het Leuven Universiteitsfonds Ped IMID (Pediatrische Immuun-inflammatoire aandoeningen) opgericht, een waarmee ze middelen willen werven om onderzoek, diagnose en behandeling mogelijk te maken voor personen die lijden aan zeldzame immuunziekten die momenteel niet door de ziekteverzekeringen worden gedekt.

 

Ook gelezen: De Staandard, Het Laatste NieuwsHet Nieuwsblad, De Morgan

Wednesday
Mar302016

Decades-old mystery disease identified and potential cure found

A mysterious inflammatory disease has been afflicting a Flemish family for three generations, causing severe skin lesions, fevers, pain and exhaustion. This disease, which previously had no known cause or cure, has now been identified as Pyrin Associated Autoinflammation with Neutrophilic Dermatosis (PAAND), and has also been found in families in England and France. New research by Adrian Liston (VIB/University of Leuven, Belgium), Seth Masters (Walter and Elisa Hall Institute, Australia), Carine Wouters (University of Leuven, Belgium) has found the genetic mutation causing the disease and also identified an effective treatment. This research was published in the international scientific journal Science Translational Medicine.

For decades, families in Belgium, England, and France have been living with a mysterious disease that results in skin lesions, fevers, pain and exhaustion. Every generation, half of the children of the people with this disease develop the same symptoms. Doctors had been previously unable to identify the disease or find any effective treatment. For the first time, this disease has been identified and a treatment found due to an international research team.

Professor Adrian Liston (VIB/University Leuven): “Detailed work by clinicians told us that we were dealing with a genetic disease. Thanks to advances in DNA sequencing technology we were able to sequence the genome of these patients and find the mutation causing the disease”.

The mutation is in the gene called MEFV. This gene was known to cause an inflammatory disease called Familial Mediterranean Fever (FMF) in patients who inherit mutated copies from both mother and father. However, the mutation found in the PAAND patients is different. Only a single copy of the mutation is needed to cause disease, meaning it affects half the children of patients, unlike the mutations that cause FMF, which often skip generations.

Professor Seth Masters (Walter and Elisa Hall Institute): “The PAAND mutation causes the body to as if there is a bacterial skin infection. This leads to the skin making the inflammatory protein interleukin-1β, which causes skin lesions, fevers and pain”.

A cure for the new disease?

Understanding the biological basis for this new disease allowed the rational selection of a new treatment. The researchers repurposed an anti-arthritis drug, anakinra, which targets the same protein that causes PAAND, interleukin-1β. The results in the first volunteer, from an English family, were striking, with a rapid clearance of skin lesions and a complete recovery from fevers and pain. A larger trial is now beginning in the Flemish patients to see if this targeted treatment will act as a complete cure.

Professor Carine Wouters (KU Leuven/UZ Leuven, lead clinical researcher): “This is the synthesis of an intense collaboration between clinicians and scientists trying to understand this disease for almost 10 years.  I am delighted to see how it has increased our understanding of rare mutations, and especially has opened a therapeutic perspective for these patients.”

Quote from one of the patients: “We are happy and very grateful to the doctors and scientists who never gave up their search to understand the disease that affected members of our family for so many years. We are very hopeful that the new treatment will be beneficial to our family. Also we realize that the findings will help other patients to get a correct diagnosis and therapy.”

Professor Adrian Liston (VIB/KU Leuven, lead scientific researcher): “This is an amazing time to be working on genetic diseases. Every month we are solving clinical cases that would have been too hard to work out just a few years ago. Actually, to be honest the research is moving much faster than the healthcare system – we are finding new mutations, new diseases and trialling new treatments faster than the healthcare system is adapting. It creates a difficult situation for patients where the science is in, but the health insurance funds are not ready to reimburse the costs of the advanced diagnostic tests we use or novel treatments that we discover. This is a challenge, but also an opportunity – medical improvements could be rolled out quite quickly with political will.”

Professors Carine Wouters and Adrian Liston have established the charity Ped IMID to seek funding for research, diagnosis, and treatment of people living with rare immune disorders not currently covered by the health insurance funds. 

To read more, go to our article in Science Translational Medicine:

Masters, Lagou, Jéru, Baker, Van Eyck, Parry, Lawless, De Nardo, Garcia-Perez, Dagley, Holley, Dooley, Moghaddas, Pasciuto, Jeandel, Sciot, Lyras, Webb, Nicholson, De Somer, van Nieuwenhove, Ruuth-Praz, Copin, Cochet, Medlej-Hashim, Megarbane, Schroder, Savic, Goris, Amselem, Wouters* and Liston*. Familial autoinflammation with neutrophilic dermatosis reveals a regulatory mechanism of pyrin activation. Science Translational Medicine. 2016 in press.

Monday
Mar212016

New study may lead to improved treatment of type 2 diabetes

Genetic cause found for loss of beta cells during diabetes development

Worldwide, 400 million people live with diabetes, with rapid increases projected. Patients with diabetes mostly fall into one of two categories, type 1 diabetics, triggered by autoimmunity at a young age, and type 2 diabetics, caused by metabolic dysfunction of the liver. Despite being labeled a “lifestyle disease”, diabetes has a strong genetic basis. New research under the direction of Adrian Liston (VIB/KU Leuven) has discovered that a common genetic defect in beta cells may underlie both forms of diabetes. This research was published in the international scientific journal Nature Genetics.

Adrian Liston (VIB/University of Leuven): “Our research finds that genetics is critical for the survival of beta cells in the pancreas – the cells that make insulin. Thanks to our genetic make-up, some of us have beta cells that are tough and robust, while others have beta cells that are fragile and can’t handle stress. It is these people who develop diabetes, either type 1 or type 2, while others with tougher beta cells will remain healthy even in if they suffer from autoimmunity or metabolic dysfunction of the liver.”

Different pathways to diabetes development

Diabetes is a hidden killer. One out of every 11 adults is suffering from the disease, yet half of them have not even been diagnosed. Diabetes is caused by the inability of the body to lower blood glucose, a process normally driven by insulin. In patients with type 1 diabetes (T1D), this is caused by the immune system killing off the beta cells that produce insulin. In patients with type 2 diabetes (T2D), a metabolic dysfunction prevents insulin from working on the liver. In both cases, left untreated, the extra glucose in the blood can cause blindness, cardiovascular disease, diabetic nephropathy, diabetic neuropathy and death.

In this study, an international team of researchers investigated how genetic variation controls the development of diabetes. While most previous work has focused on the effect of genetics in altering the immune system (in T1D) and metabolic dysfunction of the liver (in T2D), this research found that genetics also affected the beta cells that produce insulin. Mice with fragile beta cells that were poor at repairing DNA damage would rapidly develop diabetes when those beta cells were challenged by cellular stress. Other mice, with robust beta cells that were good at repairing DNA damage, were able to stay non-diabetic for life, even when those islets were placed under severe cellular stress. The same pathways for beta cell survival and DNA damage repair were also found to be altered in diabetic patient samples, indicating that a genetic predisposition for fragile beta cells may underlie who develops diabetes.  

Adrian Liston (VIB/University of Leuven): “While genetics are really the most important factor for developing diabetes, our food environment can also play a deciding role. Even mice with genetically superior beta cells ended up as diabetic when we increased the fat in their diet.”

A new model for testing type 2 diabetes treatments

Current treatments for T2D rely on improving the metabolic response of the liver to insulin. These antidiabetic drugs, in conjunction with lifestyle interventions, can control the early stages of T2D by allowing insulin to function on the liver again. However during the late stages of T2D, the death of beta cells means that there is no longer any insulin being produced in the pancreas. At this stage, antidiabetic drugs and lifestyle interventions have poor efficacy, and medical complications arise.

Dr Lydia Makaroff (International Diabetes Federation): “The health cost for diabetes currently exceeds US$600 billion, 12% of the global health budget, and will only increase as diabetes becomes more common. Much of this health care burden is caused by late-stage type 2 diabetes, where we do not have effective treatments, so we desperately need new research into novel therapeutic approaches. This discovery dramatically improves our understanding of type 2 diabetes, which will enable the design of better strategies and medications for diabetes in the future”.

Adrian Liston (VIB/University of Leuven): “The big problem in developing drugs for late-stage T2D is that, until now, there has not been an animal model for the beta cell death stage. Previously, animal models were all based on the early stage of metabolic dysfunction in the liver, which has allowed the development of good drugs for treating early-stage T2D. This new mouse model will allow us, for the first time, to test new antidiabetic drugs that focus on preserving beta cells. There are many promising drugs under development at life sciences companies that have just been waiting for a usable animal model. Who knows, there may even be useful compounds hidden away in alternative or traditional medicines that could be found through a good testing program. If a drug is found that stops late-stage diabetes, it would really be a major medical breakthrough!”

 

Read more: Dooley*, Tian*, Schonefeldt*, Delghingaro-Augusto*, Garcia-Perez, Pasciuto, Di Marino, Carr,Oskolkov, Lyssenko, Franckaert, Lagou, Overbergh, Vandenbussche, Allemeersch, Chabot-Roy, Dahlstrom, Laybutt, Petrovsky, Socha, Gevaert, Jetten, Lambrechts, Linterman, Goodnow, Nolan, Lesage, Schlenner**, Liston**. 'Genetic predisposition for beta cell fragility underlies type 1 and type 2 diabetes.' Nat Genet. 2016

Thursday
Mar102016

New study provides insight into Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a severe inflammatory disease caused by macrophage activation. Watch "Max the Angry Macrophage":

In patients with the primary (genetic) form of the disease, the underlying cause of illness is a defect in CD8 T cells which makes them inefficient at clearing viruses. The connection between this defect and the disease onset has, however, been unclear. 

In a new study from the Translational Immunology laboratory, we used a mouse model of HLH to dissect the mechanism leading to disease. We found that the CD8 T cells try to overcome their defect in anti-viral killing by becoming more and more activated. One consequence of this activity is that they start consuming a key cytokine in the blood, IL-2. IL-2 is necessary for the survival of regulatory T cells, the key cell type for calming down a hyper-active immune system. When the activated CD8 T cells consumed all of the IL-2, the regulatory T cells started dying off due to IL-2 starvation, leading to excessive inflammation. The same lack of regulatory T cells was found in HLH patients, indicating that this is the mechanism driving inflammatory disease in patients. These results identify a new therapeutic target for HLH patients.

 

Humblet-Baron S, Franckaert D, Dooley J, Bornschein S, Cauwe B, Schönefeldt S, Bossuyt X, Matthys P, Baron F, Wouters C, Liston A. 'IL-2 consumption by highly activated CD8 T cells induces regulatory T-cell dysfunction in patients with hemophagocytic lymphohistiocytosis.' J Allergy Clin Immunol. 2016 Mar 3. pii: S0091-6749(16)00115-9. doi: 10.1016/j.jaci.2015.12.1314.

Saturday
Jan162016

Journal club: Patient diagnosed with non-human cancer

In a fascinating case report in the New England Journal of Medicine, Muehlenbachs et al identified a patient with disseminated cancer through the lungs and lymph nodes. The major oddity of the cancer was the small size of the cells, far smaller than human cells, indicating that the cancer cells were non-human. Extensive analysis identified the cancer cells as coming from Hymenolepis nana, the dwarf tapeworm. The patient was infected with tapeworms, one of which developed cancer (as can happen to any organism). These tapeworm cancer cells then metasized from the tapeworm into the host, adapted to the host and spread throughout the body as a foreign cancer. While the immune system is normally highly effective at clearing foreign organisms from the body, the tapeworm cancer cells were able to survive and disseminate throughout the body, possible for a combination of three reasons: i) tapeworms induce immune tolerance against their antigens, ii) the tumour cells were selected to be of low immunogenicity, and iii) the patient was HIV+ and immunodeficient. While this may be a one-off case, since parasite infections are so common perhaps we will find non-human cancers in other patients?

Muehlenbachs et al. 'Malignant Transformation of Hymenolepis nana in a Human Host'. New England Journal of Medicine. 2015. 373:1845

Tuesday
Jan122016

Ebastine provides relief from Irritable Bowel Syndrome

In a study published today by Gastroenterology, we demonstrate in a randomized placebo controlled trial that the anti-histimine Ebastine provides relief from the symptoms of Irritable Bowel Syndrome (IBS). The study, led by Prof Guy Boeckxstaens and in collaboration with the Translational Immunology Laboratory, tested the effect of Ebastine on pain relief. Over a 12 week course, nearly 50% of IBS patients showed considerable relief from symptoms. As Ebastine is a safe over-the-counter anti-histimine, commonly prescribed for allergy, this study could be rapidly extended to millions of IBS patients across the world.

Read more: Wouters et al. 'Histamine Receptor H1-mediated Sensitization of TRPV1 Mediates Visceral Hypersensitivity and Symptoms in Patients With Irritable Bowel Syndrome'. Gastroenterology. 2016