Een kind verandert alles, vooral je immuunsysteem

Voor welke ziektekiemen we vatbaar zijn, hangt af van onze genen, ons gewicht en hoe goed we ons in ons vel voelen. Maar het belangrijkste effect hebben kinderen.

Het immuunsysteem beschermt ons tegen ziekten. Tegen welke ziektekiemen het lichaam precies gewapend is, verschilt sterk van persoon tot persoon. Een onderzoeksteam van de Leuvense tak van het Vlaams Instituut voor Biotechnologie en het Britse Babraham Institute vond in het bloed van 670 proefpersonen aanwijzingen dat mensen elkaars immuunsysteem sterk beïnvloeden. Adrian Liston leidde het onderzoek.

Professor Liston, veel jonge ouders worden ziek, zodra hun kindje naar de crèche gaat. U hebt vastgesteld dat een kind grootbrengen het immuunsysteem van de ouders verandert. Ten slechte?

‘Niet per se. We zien dat personen die samenwonen, op den duur immuunsystemen hebben die sterk op elkaar lijken. Terwijl voorheen de ene misschien zeer vatbaar was voor bacteriële ziektes en minder voor virale aandoeningen, kan hij van de ander de weerbaarheid tegen virussen overnemen. Hij is dan voortaan wel, net als zijn partner, kwetsbaar voor bacteriën. Het risico op bepaalde ziektes neemt dus door het samenleven toe, het risico op andere dan weer af.’

‘Samen een kind grootbrengen blijkt dat effect te versterken. Ons onderzoek bij kinderen en volwassenen uit België en het Verenigd Koninkrijk toont aan dat een kind voor je immuunsysteem zelfs een belangrijkere rol speelt dan je genen, je gewicht, je geslacht of hoe je je voelt.’

Hoe komt dat?

‘Als je gedurende tien seconden kust, wissel je zo’n 80 miljoen bacteriën uit. Op een gegeven moment draag je dus dezelfde bacteriën als je partner en daar reageert je immuunsysteem op. Als twee volwassenen samen voor hun kindje zorgen, wisselen ze ook via het kindje bacteriën en virussen uit.’

Als de ene ouder ziek wordt, is de ander dus ook buiten strijd?

‘Ja. Maar dat is op zich niet zorgwekkend bij personen die voor de rest gezond zijn.’

‘In een rusthuis is dat iets anders. De bewoners hebben geen intieme relatie met elkaar, maar ze wonen wel allemaal samen. Mogelijk lijken hun immuunsystemen sterk op elkaar en is de groep zeer vatbaar voor uitbraken, bijvoorbeeld van griep. Dat zouden we graag in detail verder onderzoeken.’

Courtesy of De Staandard

Think twice before you have kids!

Prof Michelle Linterman, co-lead author on our recent study on the effect of children on the immune system, has been hitting the airwaves today:

Interested? Listen here for a recap of the BBC World Service (conversation runs from 08.53-12.40), or here for the Today show (45.07).

Share a child? Then your immune systems look pretty similar too

The human immune system is shaped by family and household

Raising a child together has a greater effect on your immune system than the seasonal 'flu vaccine or travellers' gastroenteritis, a study by researchers at the VIB in Belgium and the Babraham Institute in the UK has found.

The research took a detailed look at the immune systems of 670 people, ranging from 2-86 years of age, to understand more about what drives variation in our immune systems between individuals. From an assessment of the effects of a range of factors, including age, gender and obesity, one of the most potent factors that altered an individual's immune system was whether they co-parented a child. Individuals who lived together and shared a child showed a 50% reduction in the variation between their two immune systems, compared with the diversity seen in the wider population. 

Dr Adrian Liston, a researcher at the VIB and University of Leuven who co-led the research said: "This is the first time anyone has looked at the immune profiles of two unrelated individuals in a close relationship. Since parenting is one of the most severe environmental challenges anyone willingly puts themselves through, it makes sense that it radically rewires the immune system - still, it was a surprise that having kids was a much more potent immune challenge than severe gasteroenteritis. That's at least something for prospective parents to consider - the sleep deprivation, stress, chronic infections and all the other challenges of parenting does more to our body than just gives us grey hairs. I think that any parents of a nursery- or school-age child can appreciate the effect a child has on your immune system!"

Every individual has a unique immune system, something which can be visualised as a unique location in “immunological space”. Our immune systems are also dynamic, with minor differences on a day-to-day basis. The biggest shapers of our immune systems are age, with a gradual ageing of the immune system over time, and cohabitation, where having a child together causes the unique immune signature of each individual to come much closer. Image produced by Dr Carl 

Participants in the study were assessed over a period of three years. Regularly monitoring their immune systems showed that the individuals maintained a stable immune landscape over time, even after their immune systems were triggered into action by the seasonal ‘flu vaccine or gastroenteritis. The researchers found that following immune challenge, our immune systems tend to bounce back to the original steady state, demonstrating the elastic potential of our immune system.

In assessing the effect of other factors on the immune system, such as age, obesity, gender, anxiety and depression, the study found that age is a crucial factor in shaping the immunological landscape, agreeing with the age-related decline seen in response to vaccination and reduced resistance to infection.

Dr Michelle Linterman, a researcher at the Babraham Institute who co-led the research said: “Our research shows that we all have a stable immune landscape which is robustly maintained. What is different between individuals is what our individual immune systems look like. We know that only a small part of this is due to genetics. Our study has shown that age is a major influence on what our immune landscapes look like, which is probably one of the reasons why there is a declining response to vaccination and reduced resistance to infection in older persons.”

The research is published by the leading international journal Nature Immunology and was funded by two European Research Council grants. Dr Michelle Linterman and her group at the Babraham Institute are supported by the Biotechnology and Biological Sciences Research Council.  Dr Adrian Liston and his group are members of the VIB and University of Leuven, in Belgium.

Publication: Carr et al. (2016) The human immune system is robustly maintained in multiple equilibriums by age and cohabitation. Nature Immunology

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

(Yet another) reason to vaccinate your child

Vaccination may be one of the greatest scientific breakthroughs of all time. Smallpox eradication alone probably saves 3 million lives a year, and the routine childhood vaccines save another 3 million lives a year. Vaccines are so effective and successful, in fact, that they are no longer seen with the awe they deserve. The virulent fear of infectious disease has faded so completely forgotten that clueless celebrities are happy to campaign against vaccines based on the incorrect claims of a discredited  fraud.

Take measles, for example. While often dismissed as a harmless childhood disease, measles can be a killer. It is extremely infectious virus, putting most other viruses to shame for just how incredibly infectious it is. For children or adults in poor health (immunocompromised or malnourished), measles has a mortality rate of 30%. Even under the best scenario, measles can cause blindness and brain damage and kill 0.2% of those infected. 0.2% doesn't sound that much, but consider that in the USA without vaccination we would have 3-4 million cases a year - that is 8000 infant deaths being prevented every year.

Well, it turns out that measles is probably even worse than this. A new study demonstrates that measles infection increases the risk of dying of other diseases (scientific paper here, lay verion here). When measles vaccines are introduced, it is not only deaths from measles that are eliminated - deaths from a wide set of childhood infections dramatically drop. In fact, rather than "what doesn't kill you makes you stronger", surviving measles seems to suppress the immune system for several years, making children more likely to die from alternative diseases. Vaccination gives protection against measles without the risks of infection and without the immunosuppression of infection - a great "win-win" situation.

New cause for early-onset lupus discovered

In a new study out by the Autoimmune Genetics Laboratory, we have discovered a new genetic cause for early-onset systemic lupus erythematosus - mutation in the gene IFIH1. In 2014, mutations of this gene were independently found to cause the neurodegenerative disease Aicardi-Goutières syndrome (AGS). Despite lupus and AGS manifesting as clinically different symptoms, this study shows that mutation in the same gene causes both diseases. The mutation in IFIH1 works via driving excessive production of the cytokine IFN alpha, so this discovery opens up the possibility for treatment once anti-IFN alpha antibodies (currently in development) are approved for use. 

Read more: Van Eyck, De Somer, Pombal, Bornschein, Frans, Humblet-Baron, Moens, de Zegher, Bossuyt, Wouters* & Liston*. IFIH1 mutation causes systemic lupus erythematosus with selective IgA-deficiency. Arthritis Rheumatol. 2015, in press.

If you would like to support our clinical research, and allow us to take on more cases like this one, you can make a tax-deductable donation the Ped IMID fund, by transferring to IBAN-number BE45 7340 1941 7789, BIC-code: KREDBEBB with the label "voor EBD-FOPIIA-O2010".

New fund to support translational research into paediatric inflammatory diseases

A new fund has been set up to drive bench-to-bedside research for children with inflammatory immune diseases. The Ped IMID fund (Fonds Pediatrische Immuun-inflammatoire Aandoeningen) was set up by Prof Carine Wouters (Pediatric Rheumatology), Prof Patrick Matthys (Immunobiology) and Prof Adrian Liston (Autoimmune Genetics) to build on our strong research cooperation. More than merely "translational research", where basic science is pushed into the clinic, our group performs "dialog research", where we meet regularly to discuss the clinic and the science of the most difficult-to-treat patients. We use the clinic to inform the research and the research to inform the clinic, and have already had multiple break-throughs in understanding and treating children with rare inflammatory diseases. 

If you would like to support our research, and allow us to take on more cases, you can transfer a tax-deductable donation to IBAN-number BE45 7340 1941 7789, BIC-code: KREDBEBB with the label "voor EBD-FOPIIA-O2010".

A new look at immune ageing

The thymus is the organ in which all T cells, a key white blood cell in our immune system, develop. The thymus shrinks with age, degenerating from a plump milky organ (just above the heart) to a ratty-looking fat-riddled vestige which barely produces any new T cells. This degeneration means that older persons are producing fewer and fewer T cells, contributing to the poor responses to vaccines and infections with age. Despite the importance of this process, there is a great debate in immunology over why the thymus gets worse with age, with some scientists pointing out the structural degeneration of the thymus itself, while others suggest that it is instead due to poorer function of the bone-marrow that sends stem cells to the thymus to be turned into T cells.

In a new study from the Autoimmune Genetics Laboratory, published in the European Journal of Immunology, we use a range of imaging and genetic techniques to address this key question. We undoubtly find the structural degeneration in the organ with age, but by comparing two mouse strains that have a thymus ageing at different rates, we find that the structural abnormalities do not actually limit production of T cells. Instead, it is the reduced function of the bone-marrow that leads to a reduction in new T cells. These results suggest that researchers looking into immune ageing direct their attention towards the bone-marrow, where rescuing stem cell production may allow even older persons to produce fresh T cells for a healthy life.

Data from Franckaert et al, European Journal of Immunology. The C57BL/6 mouse (top) has a thymus that ages slowly, while the FVB/N mouse (bottom) has a thymus that ages rapidly.

Jeffrey Modell Foundation supports Belgian research on primary immunodeficiency

For the first time the Jeffrey Modell Foundation is giving a research grant to a Belgian laboratory. The team of Adrian Liston from VIB-KU Leuven will use the grant to develop a gene therapy to cure children that suffer from IPEX syndrome, a rare and fatal autoimmune disorder in which the immune system attacks the body’s own tissues and organs. At the moment, the only successful therapy to treat the syndrome is a bone marrow transplantation, which is not available for all children.

 “This is a real chance for a cure”, said lead-researcher Adrian Liston. “The gene responsible for this disease was identified 13 years ago, but for the first time we may have learned enough about the basic biology to solve it. We should know within a year whether the gene therapy works in mice, after which we can move to patients at top speed.”

The Jeffrey Modell Foundation (JMF)

JMF is a global non-profit organization for patients who suffer from Primary Immunodeficiency (PI) and their relatives. The organization is devoted to early and precise diagnosis, meaningful treatments and, ultimately, cures. Through clinical and basic research, physician education, patient support, advocacy, public awareness and new-born screening they want to make a difference in the lives of patients with PI.

Vicki and Fred Modell established the Foundation in 1987, in memory of their son Jeffrey, who died at the age of fifteen from complications of PI. During the years, the foundation has created a network of the world’s leading expert immunologists. Two years ago the Child Immune Deficiencies Department of UZ Leuven was given the first certification as a "Jeffrey Modell Foundation Diagnostic and Research Center for Primary Immunodeficiencies” in Belgium.

IPEX and primary immunodeficiency (PI)

IPEX is an acronym for immune dysregulation, polyendocrinopathy (diseases affecting multiple endocrine glands), enteropathy (disorder of the intestines), and X-linked (pattern of inheritance).

IPEX Syndrome is classified as a primary immunodeficiency disorder. Primary immunodeficiencies are disorders in which part of the body's immune system is missing or does not function normally. IPEX is caused by mutations in the FOXP3 gene which lead to the dysfunction of regulatory T cells (a type of white blood cells).

IPEX syndrome is an autoimmune disorder, meaning that the immune system mistakenly attacks the body’s own tissues and organs. The syndrome is characterized by severe diarrhoea, dermatitis (inflammation of the skin), diabetes and severe, life-threatening infections. The disease only affects boys.

Current therapies still remain of partial efficacy. Immunosuppressive drugs are most commonly used, but they only delay the disease. Stem cell transplantation, when performed before severe autoimmunity develops, is currently the only effective cure. However transplantation is only a solution for those children with a compatible donor, unless a gene therapy option is available to correct the mutation in the patient’s own stem cells. 

Update on Wednesday, September 10, 2014 at 3:55PM by Adrian Liston

METRO.be

Amerikaanse beurs voor Vlaams onderzoek naar auto-immunziekte IPEX

Bio-Medicine

Jeffrey Modell Foundation supports Belgian research on primary immunodeficiency

News-medical.net

Belg ontvangt onderzoeksbeurs van Jeffrey Modell om behandelingsIPEX syndroom te helpen

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Amerikaanse beurs voor Vlaams onderzoek naar auto-immunziekte IPEX

BRF.be

Belgische Genforscher erhalten Geld einer US-Stiftung

sNEWSi.com

Jeffrey Modell Foundations supports Belgian research on primary immunodeficiency

LokaalNieuws.be

Amerikaanse beurs voor Vlaams onderzoek naar auto-immunziekte IPEX

New VIB group leader position available

The VIB is starting up a new group leader position in Hasselt University focused on autoimmunity research. The position will come with a €1.4 million start-up grant. Interested? Apply here.