immunology

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Mass. General Launches Trial Of Old TB Vaccine For Type 1 Diabetes

A blood test to check glucose levels (Alden Chadwick/Flickr Creative Commons)

A blood test to check glucose levels (Alden Chadwick/Flickr Creative Commons)

Type 1 diabetes, the autoimmune form that usually strikes young people, is big and getting bigger: As many as 3 million Americans may have it, and their numbers are growing quickly and mysteriously.

So any promise of potential progress is a big deal, and it was splashy news back in 2012 when Dr. Denise Faustman, director of the Immunobiology Laboratory at the Massachusetts General Hospital, reported positive results for a test of a tuberculosis vaccine called BCG — Bacillus Calmette-Guerin — in a tiny trial of three longtime diabetes patients. Of particular appeal: BCG has been around for nearly a century, has been shown to be safe and, long since generic, is also cheap.

Now, Faustman has just announced the launch of a far bigger human clinical trial, aiming for 150 patients from ages 18 to 65. Though BCG is known as a vaccine, the trial will use it not to prevent diabetes but to try to reverse the disease — at least partially — in patients who already have it.

Dr. Faustman’s research, funded mainly by the Iacocca Foundation, has been considered somewhat controversial, so the results of the new trial — which is expected to last five years and is a “Phase II” trial to assess how effective the treatment is — could lay that debate to rest.

Our conversation, lightly edited:

So how do you see the headline here? And should it begin ‘This is not a cure’? What’s your main message to the public?

I think the main point of what we’re doing is: These are the first trials trying to intervene immunologically in people with long-standing autoimmunity and trying to reverse the disease, but doing it with a cheap, inexpensive, hundred-year-old drug.

Dr. Denise Faustman, director of the Immunobiology Laboratory at Massachusetts General Hospital (Courtesy MGH)

Dr. Denise Faustman, director of the Immunobiology Laboratory at Massachusetts General Hospital (Courtesy MGH)

But how would you calibrate the promise, or hope, of how well this might work for people?

It’s interesting because these trials, although we were kind of the first in the world to start in Phase I, they’ve caught on, on a global basis — using repeat BCG in diverse autoimmune diseases, such as multiple sclerosis, such as Sjögren’s disease. So, although we were kind of lonely to begin with, suggesting this hundred-year-old drug might have major therapeutic impacts, we’re not so lonely anymore. In fact, in Europe, there are Phase III trials going on in multiple sclerosis.

So, we’re seeing clinical effects in patient populations where people thought it wasn’t possible to reverse or partially reverse a disease. So we’re pretty hopeful that this inexpensive way might make a significant dent on the clinical course of a disease and do it at incredible cost savings to the public.

So, does that go as far as possible ‘cure’? Continue reading

Do You Really Need That Tetanus Booster? One Man’s Ordeal

A patient suffering from tetanus (painting by Sir Charles Bell, 1809, via Wikimedia Commons)

A patient suffering from tetanus (painting by Sir Charles Bell, 1809, via Wikimedia Commons)

By David C. Holzman
Guest Contributor

I didn’t think it was a big deal. I’d stepped on a shell in Wellfleet Harbor, and it had sliced into my foot, and drawn blood. Heck, I didn’t even think tetanus bacteria hung out in salt water — they like soil, especially if the icing atop its cake is manure. But my anguished Jewish mother was all “get over to AIM [the local health clinic] right away, before lockjaw has a chance to set in.”

Of course, the power of the Jewish Mother to inflict fear and guilt is legendary. So I ultimately hauled my derriere over to AIM. But there was a problem.

I had first learned I was allergic to tetanus shots when I was 17 — two decades earlier. I don’t remember what I’d stepped on, but I’d ended up having to go back to AIM a couple of hours after the tetanus shot, so that they could check out the hives that had sprouted from feet to nether regions to scalp. While I was in no immediate danger, I was advised that the specter of anaphylactic shock loomed over any future tetanus shots.

But now at AIM once again, I wasn’t anticipating a problem because a year after the hives, I’d stepped on something on a trip in England. But the nice doctor who had given me that injection swore that he’d quit the profession if the preventive shot he’d given me with the tetanus shot failed to protect me from hives, or any other reaction.

So I figured the docs at AIM would also know what to give me to prevent a reaction. But instead, they gave me some gobbledygook about how I should really wait until I got home — which was Washington, D.C. at the time — and let my own doc give me the shot. But the docs at Group Health, my then-HMO, were equally stymied by my predicament. Continue reading

What New Peanut Study Means For Kids With Food Allergies — And What It Doesn’t

In this undated photo provided by Cambridge University Hospitals NHS Foundation Trust, Dr. Andrew Clark of Cambridge University, right, performs a skin prick test, which is used to diagnose food allergies, on Lena Barden, 12, during clinical trials at Addenbrooke's Hospital Clinical Research Facility, Cambridge, England. An experimental therapy in Britain that fed children with peanut allergies small amounts of peanut flour has helped more than 80 percent of them eat a handful of the previously worrisome nuts safely. (Cambridge University Hospitals NHS Foundation Trust/AP)

In this photo provided by Cambridge University Hospitals NHS Foundation Trust, Dr. Andrew Clark of Cambridge University, right, performs a skin prick test, which is used to diagnose food allergies, on Lena Barden, 12, during clinical trials at Addenbrooke’s Hospital Clinical Research Facility, Cambridge, England. (Cambridge University Hospitals NHS Foundation Trust/AP)

By Richard Knox

Erin Brazil is frustrated. She’d hardly had time to digest the peanut allergy study that got heavy media coverage this week when, she says, she got “inundated by calls and emails and Facebook posts saying ‘There’s a cure, there’s a cure!’ ”

Brazil is a Boston food-allergy activist whose 4-year-old son Gabriel is severely allergic to peanuts and other foods. So she knows better than anyone that the new study, while a landmark in the field, represents no cure. “It doesn’t do anything for Gabriel,” she says.

What it does mean is that many future children will be able to avoid a life of worry about whether the merest trace of peanut protein — even an invisible smear from a candy bar left by another child on playground equipment — could send them to the emergency room gasping for breath.

I can finally look a mother in the eye and give her some advice that I feel confident in.

– Dr. Hugh Sampson

And the new study means that the recommendations parents have been given over the past 15 years — to withhold peanuts until the age of 3 in children deemed at risk — “were exactly wrong,” says Dr. Wayne Shreffler, director of the Food Allergy Center at Massachusetts General Hospital.

“I strongly suspect they made things worse,” Streffler adds, because at-risk children who were deprived of peanut exposure in food during infancy were more likely to suffer a lifelong allergy from later exposure to, say, house dust. It’s almost impossible to avoid it.

In 2008, the American Academy of Pediatrics withdrew its recommendation to withhold peanuts until age 3, but until now there’s been no solid evidence in favor of deliberately feeding peanuts to at-risk kids. That’s what the new study strongly suggests parents should do — strictly under the supervision of their pediatricians. That flip-flop is widely expected to be enshrined in the next set of official guidelines.

It’s a big change, but not only does it offer nothing to children like Gabriel who already have peanut allergy, it provides no answer to the really big question: Just why have food allergies soared lately, more than quadrupling among the current generation of American children?

Even though the study doesn’t solve that mystery, allergy experts say it’s certain to accelerate research already under way to unravel the causes and devise treatments, if not outright cures.

Six million U.S. children currently have food allergies, one out of every 13 kids, according to the largest recent study. Peanut allergy is the most common, and the most troublesome — not only because it’s so hard to avoid exposure, but because peanut allergy is usually permanent, unlike those involving other foods. And peanut allergies are more likely to be fatal.

That explains why allergists are so enthusiastic about the new study. Continue reading

The Importance Of Being Mucus

(jacobspencer/Flickr)

(jacobspencer/Flickr)

You may think mucus is nothing more than the lowly byproduct of a sneeze or the thick goo that spews from a hacking cough. But mucus is actually one of the many important players of your immune system. Your nose, mouth, throat, lungs, stomach, intestinal tract, genital area — pretty much anything that comes in contact with stuff from the outside world — all have mucosa membranes. Now scientists are one step closer to harnessing the power of mucus at catching and trapping viruses.

Researchers, led by Katharina Ribbeck, MIT professor of biological engineering, added to the growing body of evidence that mucins (proteins abundant in mucus) are perhaps the magic virus-fighting ingredient. Anne Trafton of the MIT News Office wrote about the new findings — here’s an excerpt:

For this study, which appeared in a recent issue of the journal Biomacromolecules, Ribbeck and her students created a gel from purified mucins. The researchers coated human epithelial cells with a layer of this gel and then exposed them to human papilloma virus, influenza A and Merkel cell polyomavirus. All three viruses were trapped in the mucin gel, preventing them from infecting the cells.

Ribbeck speculates that the viruses are trapped by the sugar molecules found on mucins. Continue reading

The Giant, Inflatable, Walk-Through Cell

The Giant Cell on display in the Atrium in Technology Square as part of the Cambridge Science Festival. The Giant Cell is a joint project of the University of Basel and Interpharma. (Nate Goldman/WBUR)

The Giant Cell on display as part of the Cambridge Science Festival. (Nate Goldman/WBUR)

Biology is much more fun in 3D — especially if you can touch, squeeze, recline on, peek into and walk through it.

On Tuesday night I got to experience The Giant Cell, an inflatable, interactive exhibit part of the Cambridge Science Festival. It’s a joint project of the University of Basel and Interpharma (a trade association for Swiss pharmaceutical companies).

And yes, The Giant Cell is giant — it’s 300,000 times larger than a cell in your body. But all the parts were there: the nucleus, the ribosomes, the mitochondria, you name it. This was science education at its best. And biggest.
Continue reading

Flavors Of Spring Misery: How Allergies Differ From Colds

Cold or allergy? The symptoms can be similar, but colds include fever and last only for days. Allergies don't include fever and last for weeks.

Your nose feels like an ever-streaming faucet. Your sinuses are overflowing cranial pools. Your brain is stuffed with mental batting. Ah, spring!

But which is it? Allergies or a cold? Children’s Hospital Boston sent over the lovely Venn Diagram above, and also connected me with Dr. Andrew MacGinnitie, associate clinical director of its Division of Immunology.

“If it’s starting now,” he said, “It could be a cold but it’s probably allergies, because I’m hearing from people who have spring allergies that the trees are starting to bud and the tree pollens are starting to get out there.” The allergies normally don’t kick in until April, he noted, but the mild weather appears to be having an effect. And if you feel this way every spring, that’s still further indication that it’s allergies.

Other points of distinction: A cold will typically last a few days and be gone; seasonal allergies tend to last weeks. And colds often cause fever while allergies don’t (Hay fever is a misnomer, he notes, though it does convey how systemically ill people feel.) Tree pollen allergies tend to peak in May; it remains to be seen how this year’s weather will affect that.

At what point, I asked, do you say, ‘I don’t think what I have is just a cold?’ Continue reading