Caltech Research Finds Link between Immune Irregularities and Autism

Scientists at the California Institute of Technology (Caltech) pioneered the study of the link between irregularities in the immune system and neuro-developmental disorders such as Autism a decade ago.

Since then, studies of postmortem brains and of individuals with autism, as well as epidemiological studies, have supported the correlation between alterations in the immune system and autism spectrum disorder.

What has remained unanswered, however, is whether the immune changes play a causative role in the development of the disease or are merely a side effect.

Now a new Caltech study suggests that specific changes in an overactive immune system can indeed contribute to autism-like behaviours in mice, and that in some cases, this activation can be related to what a developing fetus experiences in the womb.

The results appear in a paper this week in the Proceedings of the National Academy of Sciences (PNAS).

"We have long suspected that the immune system plays a role in the development of autism spectrum disorder," says Paul Patterson, the Anne P. and Benjamin F. Biaggini Professor of Biological Sciences at Caltech, who led the work.

"In our studies of a mouse model based on an environmental risk factor for autism, we find that the immune system of the mother is a key factor in the eventual abnormal behaviors in the offspring."

The first step in the work was establishing a mouse model that tied the autism-related behaviors together with immune changes.

Several large epidemiological studies—including one that involved tracking the medical history of every person born in Denmark between 1980 and 2005—have found a correlation between viral infection during the first trimester of a mother's pregnancy and a higher risk for autism spectrum disorder in her child.

To model this in mice, the researchers injected pregnant mothers with a viral mimic that triggered the same type of immune response a viral infection would.

"In mice, this single insult to the mother translates into autism-related behavioral abnormalities and neuropathologies in the offspring," says Elaine Hsiao, a graduate student in Patterson's lab and lead author of the PNAS paper.

The team found that the offspring exhibit the core behavioral symptoms associated with autism spectrum disorder—repetitive or stereotyped behaviors, decreased social interactions, and impaired communication.

In mice, this translates to such behaviors as compulsively burying marbles placed in their cage, excessively self grooming, choosing to spend time alone or with a toy rather than interacting with a new mouse, or vocalizing ultrasonically less often or in an altered way compared to typical mice.

Read more at: medicalxpress.com

Aberdeen Scientists claim artificial light is key to treating Multiple Sclerosis

Aberdeen scientists have found that artificial sunlight can have a “striking effect” in helping treat sufferers of diseases such as multiple sclerosis.

Researchers from Aberdeen University studied patients in the north of Scotland – which has the highest rate of MS in the UK - who were being treated during winter with artificial UV (ultraviolet)-B light therapy for skin diseases caused by their immune systems acting inappropriately.

The research - published in the Journal of Allergy and Clinical Immunology – shows how UV-B light boosts vitamin D, as well as cells in our body that are responsible for regulating or balancing the immune system. Vitamin D is made in our bodies by UV-B light from the sun.

Some studies have suggested a link between vitamin D deficiency and autoimmune diseases such as MS.

This possible link might also explain the increasing prevalence of autoimmune disease among those living far from the equator, where there are lower levels of winter sun.

Autoimmune diseases - like MS and type 1 diabetes - are diseases where the immune system mistakenly attacks the body’s own tissues or harmless substances that enter the body.

Dr Anthony Ormerod, clinical reader in dermatology at the university, said: “Our study shows that UV-B light, which mimics sunshine, can have a striking effect on the immune system of patients.

“We found that UV-B light boosted the production of vitamin D, and of regulatory T cells, which play an important role keeping our immune systems in check.

“Our findings have important implications for future interventions including the recommendations for healthy lifestyle and a possible role for phototherapy and/or vitamin D supplementation in the prevention or treatment of autoimmune and inflammatory diseases.

“While too much exposure to sunlight is harmful and increases skin cancer risk, these results suggest that subjects in our study would have some benefits from small amounts equivalent to summer exposure in the winter but more work needs to determine the role of sunlight and the role of supplementing the diet with vitamin D.”

Dr Helen Macdonald, senior lecturer in nutrition and translational musculoskeletal research at the university and chair of the National Osteoporosis Society Nutrition and Lifestyle forum, said: “There are risks associated with high levels of both therapies, so it is important that we get the balance right.

“We would also want to stress that we are not advocating sun bed use since this is not the same type of radiation produced by sun beds which already have well-documented health risks.

“The average dose of UV light that the volunteers received was the equivalent to sunlight exposure in Aberdeen over spring and summer and further work is required to determine if lower doses are effective.”

Professor Mark Vickers, chair in applied medicine at the university, added: “Ours is the first study to demonstrate in patients a cause and effect between UV light, vitamin D and systemic immune function in people.”