The human immune system includes about a dozen major cell
types with specialized roles in the body’s defenses. They serve as sentries,
identify threats, mobilize troops, capture and transport invaders, interrogate
and kill those deemed dangerous and clear the battlefield of casualties. This intricate
command-and-control system is what enables us to fend off most of the dangerous
bacteria and viruses that come our way.
But in patients who suffer from inflammatory bowel disease (IBD), the immune system itself becomes the enemy. Even when the body faces no threat, immune cells called “helper T cells” take up arms, resulting in a kind of perpetual warfare that — far from being helpful — causes collateral damage to the gut.
“The system goes into overdrive,” says Yu Hui Kang, an
immunology graduate student at Harvard Medical School and a researcher at
Boston Children’s Hospital.
“These cells have gone too far, and they can’t stop.”
Now Kang and colleagues in the lab of Scott Snapper, MD, PhD, director of Boston Children’s Inflammatory Bowel Disease Center, may have found a way to turn the tables on the immune system by recruiting its own “natural killer” cells to wipe out the harmful T cells. Though clinical applications are years away, the work suggests new avenues for developing treatments for the debilitating disease.
Boston Children’s Hospital has embarked on a strategic initiative to accelerate and expand its research genomics gateway, with plans to sequence the DNA of 3,000 patients with epilepsy or inflammatory bowel disease and their family members. Patients will have access to enroll in this pilot study if their condition is of likely genetic origin but lack a diagnosis after initial clinical genetic testing.
Sequencing will cover the entire exome, containing all of a person’s protein-coding genes. The Epilepsy and IBD were chosen for the pilot because Ann Poduri, MD, MPH and Scott Snapper, MD, PhD, have already made huge inroads into the genetics of these respective disorders. Both have built large, well characterized patient databases for research purposes, have disease-specific genetic expertise and have begun using their findings to inform their patients’ care. …
Could an exciting potential treatment for inflammatory bowel disease (IBD) be found in the gastrointestinal tract itself? That’s the theory behind a pair of new studies by Stacy A. Kahn, MD, which will investigate the potential role of fecal microbial transplant (FMT) in the treatment of Crohn’s disease and ulcerative colitis in children.
In IBD, the immune system attacks healthy cells in the digestive tract, triggering symptoms such as abdominal pain, fatigue, poor growth and bloody diarrhea. Children with IBD can also experience problems elsewhere in the body, including joint pain, liver disorders and eye inflammation.
Known colloquially as the “poop pill,” or “stool transplant,” FMT harnesses growing knowledge about the gut microbiota, the collection of bacteria and other microbes that populate our GI tract. …
Reports from parents and a growing number of studies over the past 10 to 15 years suggest that children with autism spectrum disorder (ASD), especially more severe ASD, are prone to gastrointestinal disorders. Researchers have attributed the association to altered GI microbiota, abnormal intestinal physiology, immune alterations and other mechanisms. Some speculate that the connection results from unusual eating patterns in children with ASD.
Looking at IBD (Crohn’s and colitis) sets the bar a little higher, since IBD is uncommon and also unlikely to be caused by dietary factors (though it can certainly be aggravated by them). In a new study in the journal Inflammatory Bowel Disease, Kohane and colleagues crunched three large databases to create what they believe is the largest ASD/IBD study to date. …
Inflammatory bowel disease (IBD) is miserable for anyone, but when it strikes a child under age 5, it’s much more severe, usually causing bloody diarrhea, wrenching abdominal pain and stunted growth. Early-onset IBD is rare, but on the rise: For reasons unknown, its incidence is increasing by about 5 percent per year in some parts of the world.
A recently identified form of early-onset IBD shows up within months of birth, causing severe inflammation in the large intestine and abscesses around the anus. Recently linked to genetic mutations in the cellular receptor for a signaling protein, interleukin-10 (IL-10), it can also lead to lymphoma later in life.
As with all early-onset IBD, IL-10-receptor deficiency has no good treatment. A bone marrow transplant is actually curative, but carries many risks, especially in infants.
“We’ve been trying to understand why IBD in these children is so severe and presents so early,” says Dror Shouval, MD, a pediatric gastroenterologist at Boston Children’s Hospital and a fellow in the lab of Scott Snapper, MD, PhD. The beginnings of such an understanding—detailed recently in the journal Immunity—could lead to a new treatment approach for this and perhaps other kinds of early-onset IBD. …
In 2009, The New England Journal of Medicine reported the case of an otherwise healthy 2-year-old boy in Canada who died after surgery. He had received a codeine dose in the recommended range, but an autopsy revealed that morphine (a product of codeine metabolism) had built up to toxic levels in his blood and likely depressed his breathing. Genetic profiling revealed him to be an “ultrarapid codeine metabolizer,” due to a genetic variation in an enzyme known as CYP2D6, part of the cytochrome P-450 family.
While codeine is no longer used at Boston Children’s Hospital, it’s this kind of genetic profiling that Shannon Manzi, PharmD, would someday like to offer to all patients—before a drug is prescribed.
Not all people respond the same way to drugs. The results of randomized clinical trials—considered the gold standard for drug testing—often produce a dose range that worked for the majority of the patients in the study. They don’t take people’s individuality into account, and that individuality can dramatically affect drug efficacy and toxicity.
Adverse reactions are more common than you might think. …
Your doctor has a lot of tools to detect, diagnose and monitor disease: x-rays, MRIs, angiography, blood tests, biopsies…the list goes on.
What would be great would be the ability to test for disease in a way where there’s no or low pain (not invasive) and lots of gain (actionable data about the disease process itself, its progression and the success of treatment).