1.PASSIVE VOICE
Text 1 :
Young immune systems are sensitive to food allergens if they don’t have the right gut bacteria, a study in mice suggests.
Sung-Wook Hong of the Institute for Basic Science in South Korea and his colleagues have been investigating the effects of the microbiome on allergies and the immune system. They wondered why mice raised in a sterile environment without any gut microbes suddenly produce high levels of a type of antibody when they are weaned onto solid food.
These immunoglobulin E (IgE) antibodies form the arm of our immune system that mediates allergic responses to certain chemicals. When IgE antibodies detect allergens, they trigger the release of inflammatory chemicals that lead to the symptoms of allergies.
To understand why IgE spikes in microbe-free mice during weaning, the team fed young mice either a normal diet or one formulated with just the necessary amino acids, vitamins and glucose – nothing that could provoke the immune system. They found that the mice on the normal diet spontaneously developed an immune response, while the ones on the antigen-free diet did not.
This suggests that the lack of a healthy gut microbiome is linked to a food-triggered immune response in mice, says Hong.
However, when the team delayed introducing normal solid food until the microbe-free mice were adults, they found that they produced less IgE antibodies.
The team found that a special type of immune cell, called T follicular helper cells, were involved in the IgE response seen in the mice. This kind of T cell is mostly generated early in life.
This finding helps explain why allergies are more common in children than adults, says Hong.
When the team let the microbe-free mice mix with normal mice, they found that they stopped producing as many T follicular helper cells, and their levels of IgE antibodies fell.
“One of the implications of this study is that what is happening to your microbiota at the time of introduction of the food antigens is important,” says Emma Hamilton-Williams at the University of Queensland, Australia. “In that first year of life, the gut microbiota is really developing and changing quickly, so there definitely seems to be a connection,” she says.
In humans, good gut bacteria can be killed off by antibiotics, illness or radiation. The findings raise questions about how soon certain foods should be given to young children after antibiotics, says Elissa Deenick at the University of New South Wales.
Read more: https://www.newscientist.com/article/2204286-gut-microbes-may-determine-whether-infants-develop-food-allergies/#ixzz6RRN6kEQv
Read more: https://www.newscientist.com/article/2204286-gut-microbes-may-determine-whether-infants-develop-food-allergies/#ixzz6RRN46oCa
Read more: https://www.newscientist.com/article/2204286-gut-microbes-may-determine-whether-infants-develop-food-allergies/#ixzz6RRMzrEnL
Read more: https://www.newscientist.com/article/2204286-gut-microbes-may-determine-whether-infants-develop-food-allergies/#ixzz6RRMvYjSe
Text 2 :
It’s a terrible dilemma: a treatment that might cure you or kill you.
This is what some people with severe multiple sclerosis now face. A radical approach that wipes out the immune system and then reboots it with stem cells has stopped the devastating disease in its tracks in 70 per cent of the people who have tried it. But of the 24 people taking part in the trial, one died from liver damage and an infection while their immune system was impaired.
“I took a leap of faith. I felt like I would be kicking myself if I didn’t take this chance,” says Jennifer Molson of Ontario Canada, who had the treatment. When she decided to try it 14 years ago, she was using a wheelchair. About 18 months later, she began to notice physical improvements, and within three years she had gone back to work. Today, her life has returned to normal.
In multiple sclerosis, the immune system attacks the protective coating around nerve cells in the brain, spinal cord and optic nerves. It tends to come and go in flare-ups that get worse over time, and can eventually leave people paralysed and blind. Existing drug treatments can lessen the severity or frequency of attacks but are not a cure and don’t work for some.
Although the immune reboot is only supposed to stop MS, not reverse it, some people regained much of their functioning in the years that followed, suggesting the nervous system slowly repairs itself if the damage is not too severe.
Accidental cure
The treatment was discovered in people with leukaemia who also happened to have MS. Leukaemia is a cancer of the immune cells, and can be treated by first extracting some of a person’s bone marrow cells and then killing all the immune cells that remain in the body with toxic chemotherapy.
The stored bone marrow sample is then purged of cancerous cells and injected into the person’s blood to repopulate their immune system. Surprisingly, this treatment happened to be effective not only for leukaemia but also MS.
We don’t know what makes immune cells attack nerve cells in MS. One theory is that it is triggered by viruses that have similar proteins to those on the surface of human nerve cells. It could be that rebooting the immune system cures MS because any memory of a virus like this is wiped out.
Several centres around the world are now offering this procedure as an experimental treatment for people who have an aggressive form of MS and who are not benefiting from standard drugs. Because of the serious risk of infection while the immune system is down, most places offer a milder form of chemotherapy, but this makes it more likely that some of the nerve-targeting immune cells will survive.
Radical treatment
The regime in the latest study – which began in 2000 but was published this week – is more intense, designed to kill all the immune cells in a person’s body. “It’s important that patients recognise that this is not a cakewalk,” says Mark Freedman of Ottawa Hospital Research Institute in Ontario.
As well as the risk of infection, people lose their hair and fingernails, and suffer nausea and diarrhoea. The chemotherapy renders them infertile by killing sperm or eggs, and pushes women into early menopause. They tend to stay in hospital for a month, with their new bone marrow infused around day 11, before the last of their old immune cells have died off.
But infection is still a grave risk. Freedman hopes that as the approach is refined, the death rate will come down. At the moment it is about 1 per cent of those treated, he says, not as bad as the 4 per cent that the 24-person trial suggests. The team is now using a different version of one of the chemotherapy drugs that is less likely to cause the liver complications that may have contributed to the person’s death in this study.
John Snowden of Sheffield Teaching Hospital in the UK says that less intense chemo regimes – such as the one his centre uses – are a safer option. “We still need to find the sweet spot between toxicity and effectiveness,” he says.
The approach of rebooting the immune system is also being investigated for other severe autoimmune diseases. These include Crohn’s disease, in which the immune system attacks the bowel, and a rare skin condition called scleroderma.
Read more: https://www.newscientist.com/article/2093280-extreme-cure-for-ms-reboots-immune-system-but-can-be-fatal/#ixzz6RRYHyVeW
2. MODALS
More than 7000 people worldwide are thought to have bought parasitic worms online and ingested them in an attempt to treat conditions ranging from depression to inflammatory bowel disease. Now, a type of pig worm is being evaluated for approval as a food ingredient in Germany. If accepted, it will become the first officially approved product of its kind in Europe.
The idea for intentionally infecting yourself with parasites is that, until recent improvements in hygiene, they were common inhabitants of our bodies, having evolved to secrete substances that pacify our immune systems, so they can live in our guts. Detlev Goj, of Thai company Tanawisa, thinks that, in eliminating the problem of parasites – particularly the human hookworm – we may have overlooked possible benefits some parasites may have.
Hookworms are bad – they can cause diarrhoea, pain, anaemia and weight loss. Thankfully, they are no longer a common problem in rich nations. But parts of the world where parasitic worms are still common haven’t had the same rises in immune conditions like allergies, inflammatory bowel problems, type 1 diabetes and multiple sclerosis that have been seen in richer nations.
“Most research has been focused on hookworm disease, and we’ve overcome that but overshot slightly,” says William Parker of Duke University Medical Center in Durham, North Carolina. “We need to scale back and find a happy medium.”
Hookworm alternative
To avoid the downsides of the human hookworm, Goj’s team have been looking for parasites in other animals that may cause milder infections in people, while also helping to calm our immune system. They settled on the pig whipworm (Trichuris suis). This parasite’s eggs can survive passage through the stomach, with larvae emerging in the caecum, a pouch-like region of the gut where the small and large intestines meet.
Because these worms are adapted to living in pigs, they can’t survive for very long in humans. When the team tested them as a possible treatment for the intestinal condition Crohn’s disease, they found no evidence of the worms reproducing, and the parasites were only visible in colonoscopies for a short period after ingesting the eggs. Together, this suggests the worms are probably starving to death and being digested within a month.
After promising, small studies, Goj and colleagues ran a large, placebo-controlled trial of pig whipworms as a treatment for Crohn’s disease, but it was stopped early by a monitoring committee after participants showed no benefits within three months. Goj believes this was too soon, partly because it takes 20 weeks or longer for the benefits of worms to kick in.
Nevertheless, Goj’s team did get a whipworm product approved in Thailand in 2012, on the basis that it is a natural product and tests had found no ill-effects. This helped fuel growing demand online for approved and unapproved parasite products. When Parker surveyed self-treaters, their doctors and online suppliers of parasitic worms in 2015, he calculated that around 7000 people were giving themselves worms worldwide, to treat a wide range of autoimmune and mental health conditions.
“Self-medication with any type of worm is not recommended and it is important to remember they’re not in any way completely harmless, and may cause quite severe side effects if not monitored very carefully by a doctor,” says Helena Helmby at the London School of Hygiene and Tropical Medicine.
Mixed response
However, a range of trials with various kinds of live worms have been conducted or are in progress, says Gabriele Sorci at the University of Burgundy, France, and the results seem to indicate that such infections can alleviate the symptoms of inflammatory diseases.
Now Germany’s Federal Office of Consumer Protection and Food Safety has accepted Goj’s whipworm product for official evaluation. If approved, it could be legally sold in high street shops, and it may then go on to be approved by other European Union member states, making it the first live worm product approved for sale as a food ingredient in Europe.
“This is the first live worm product to get this far,” says Goj. He hopes to sell small vials of the product, each containing 500, 1000 or 2500 eggs of the pig whipworm, to be consumed in food or drink.
Unlike medical drugs, novel food ingredients don’t need to be shown to work in a particular way for approval in the EU – all that is needed is evidence that they are safe. So the question of whether such worms really can treat autoimmune disorders remains open.
The application has been met with a mixed response. “In my opinion, worm therapies belong in the same category of pseudoscience cult therapies as chelation therapy for autism,” says Peter Hotez of Baylor College of Medicine, Texas. He suggests that approving live worm or worm egg treatments in Germany would be a “dumb idea”.
“It would be better if we had more studies, but I’m actually not terribly concerned about this,” says Aaron Blackwell at the University of California, Santa Barbara. He says dangerous side effects might be possible if, for example, worms are able to move out of the gut into other parts of the body, but this is very rare. “Probably, taking these eggs may be no worse than many other dietary supplements that many people use regularly,” he says.
Read more: https://www.newscientist.com/article/2142897-parasitic-worm-eggs-may-soon-be-legally-sold-as-food-in-germany/#ixzz6RRQ5I7Sc
Read more: https://www.newscientist.com/article/2142897-parasitic-worm-eggs-may-soon-be-legally-sold-as-food-in-germany/#ixzz6RRPzgPkl
Read more: https://www.newscientist.com/article/2142897-parasitic-worm-eggs-may-soon-be-legally-sold-as-food-in-germany/#ixzz6RRPpcKv3
