(Press-News.org) An immune cell protein, ID2, is critical for the maintenance of healthy gut microbiota and helps these good bacteria fight off harmful bacteria, report scientists from the University of Chicago. The study, published in Immunity on April 21, suggests that novel therapeutics or microbiota transplantation could be used to promote the development of good gut microbiota to indirectly kill harmful bacteria for patients with recurrent gut infection.
"Our study reveals how our body's immune system shapes the gut microbiota to naturally limit infections," says senior author Yang-Xin Fu, MD, PhD, Fanny L. Pritzker Professor of Pathology at the University of Chicago. "Given the rapid raise of harmful bacteria that are resistant to antibiotics, it is paramount that scientists find methods of limiting harmful bacterial infections without the use of antibiotics."
The human body is made up of roughly 10 times more bacterial cells than human cells. These microorganisms, collectively called the microbiota, are thought to affect health and disease, but their precise role is still poorly understood. Recent evidence has shown that gut microbiota can help protect against infections caused by harmful bacteria - for example, fecal microbiota transplantation has been used to help some patients with difficult-to-treat Clostridium difficile infections.
To study the interaction between hosts, gut microbiota and harmful bacteria, Fu and his colleagues focused on immune system cells known as type 3 innate lymphoid cells (ILC3s), which are essential for infection resistance in the gut. They found that the protein ID2 is central to this protective effect. ILC3s that are missing ID2 have a diminished ability to respond to harmful bacterial infections.
To test how ID2 affected healthy gut microbiota, the team transferred microbiota from a mouse with ILC3s that lacked ID2 into a completely germfree mouse. These mice were highly susceptible to harmful bacterial infection. However, germfree mice that received microbiota from normal mice had dramatically reduced harmful bacterial populations.
The researchers found that mice with ILC3s that lacked ID2 were unable to produce the cytokine IL-22and subsequently induce antimicrobial peptides (AMPs) by intestinal epithelial cells,. This disrupted the health of the native gut microbiota, which then allowed harmful bacteria to colonize the gut.
"The body's immune system is needed to help shape our gut microbiota, which is the first line of protection against harmful bacteria," Fu said. "Without the presence of IL-22 and AMPs from ILC3s, the normal gut microbiota is not properly developed and thus harmful bacteria can more easily infect the body."
Fu and his colleagues believe the discovery of this mechanism could lead to novel therapeutic options to help prevent harmful infections, instead of just responding to them. The findings better inform microbiota transplantation research, and have the potential to aid in the development of new drugs or probiotics that promote good microbiota or mimic their products against various pathogens.
The team are now focusing on isolating specific microbiota species that can help prevent bacterial infections, as well as another intriguing question: how do immune cells distinguish between beneficial and harmful bacteria to maintain a healthy microbiota? Although this is still unclear, Fu notes that the human body and its microbiota have evolved to live in harmony over millions of years.
"This mutual beneficial relationship provides us with the ability to properly receive all of the nutrients from our food, and as shown with this study, the ability to limit harmful bacterial infections," he says.
INFORMATION:
The study, "Innate lymphoid cells control early colonization resistance against intestinal pathogens through Id2?dependent regulation of microbiota," was supported by the National Institutes of Health. Additional authors include Xiaohuan Guo, Liang Yong, Yuan Zhang, Anna Lasorella and Barbara Kee.
The immune system is designed to protect us from disease. But what if it was malfunctioning? Would it make a disease worse? That appears to be the case with Rett syndrome, a neurodevelopmental disorder, and possibly in other neurological disorders as well, new research from the University of Virginia School of Medicine has found.
UVA's discovery suggests that immune cells bearing a mutation in the Rett gene, MeCP2, cannot perform their normal function and are instead amplifying the disease. By identifying a new role of the immune system in the disorder, through cells ...
In order to sing or speak, around one hundred different muscles in our chest, neck, jaw, tongue, and lips must work together to produce sound. Beckman researchers investigate how all these mechanisms effortlessly work together--and how they change over time.
"The fact that we can produce all sorts of sounds and we can sing is just amazing to me," said Aaron Johnson, affiliate faculty member in the Bioimaging Science and Technology Group at the Beckman Institute and assistant professor in speech and hearing science at Illinois. "Sounds are produced by the vibrations of ...
COLUMBUS, Ohio - It's estimated that six out of 1,000 children worldwide are affected by autism spectrum disorder (ASD), and 50 percent demonstrate serious and disruptive behavior, including tantrums, aggression, self-injury and noncompliance.
For children with ASD, serious disruptive behavior interrupts daily functioning and social skills development, limits their ability to benefit from education and speech therapy, can increase social isolation and intensify caregiver stress.
Luc Lecavalier and his team of researchers from The Ohio State University Wexner Medical ...
In a small study that included seven children and teens with Wiskott-Aldrich syndrome, a rare immunodeficiency disorder, use of gene therapy resulted in clinical improvement in infectious complications, severe eczema, and symptoms of autoimmunity, according to a study in the April 21 issue of JAMA, a theme issue on child health.
Wiskott-Aldrich syndrome (WAS) is caused by loss-of-function mutations in the WAS gene. The condition is characterized by thrombocytopenia (low platelet count), eczema, and recurring infections. In the absence of definitive treatment, patients ...
In a study that included approximately 95,000 children with older siblings, receipt of the measles-mumps-rubella (MMR) vaccine was not associated with an increased risk of autism spectrum disorders (ASD), regardless of whether older siblings had ASD, findings that indicate no harmful association between receipt of MMR vaccine and ASD even among children already at higher risk for ASD, according to a study in the April 21 issue of JAMA, a theme issue on child health.
Although a substantial body of research over the last 15 years has found no link between the MMR vaccine ...
A 24 week parent training program, which provided specific techniques to manage disruptive behaviors of children with autism spectrum disorder, resulted in a greater reduction in disruptive and noncompliant behavior compared to parent education, according to a study in the April 21 issue of JAMA, a theme issue on child health.
Autism spectrum disorder (ASD) affects an estimated 6 per 1,000 children worldwide and is a major public health challenge. As many as 50 percent of children with ASD exhibit behavioral problems, including tantrums, noncompliance, aggression, and ...
In a pilot study that included children at high risk for type 1 diabetes, daily high-dose oral insulin, compared with placebo, resulted in an immune response to insulin without hypoglycemia, findings that support the need for a phase 3 trial to determine whether oral insulin can prevent islet autoimmunity and diabetes in high-risk children, according to a study in the April 21 issue of JAMA, a theme issue on child health.
A few specific proteins are often the trigger for immune responses that cause autoimmune diseases. This has led to the experimental use of antigenspecific ...
The incidence of a potentially life-threatening complication of diabetes, diabetic ketoacidosis, in youth in Colorado at the time of diagnosis of type 1 diabetes increased by 55 percent between 1998 and 2012, suggesting a growing number of youth may experience delays in diagnosis and treatment, according to a study in the April 21 issue of JAMA, a theme issue on child health.
Diabetic ketoacidosis (DKA) at the time of type 1 diabetes (T1D) diagnosis has detrimental long-term effects and is characterized by dangerously high blood sugar and the presence of substances in ...
A multi-site study sponsored by the National Institute of Mental Health (NIMH) finds young children with autism spectrum disorder and serious behavioral problems respond positively to a 24-week structured parent training. The benefits of parent training endured for up to six months post intervention.
Published in the April 21 issue of the Journal of the American Medical Association the study found parent training was more effective in reducing disruptive and aggressive behavior than 24 weeks of parent education. Parent training provided parents with specific strategies ...
Researchers from the University of Tokyo have revamped an old e-paper concept to make an inexpensive handwriting-enabled e-paper well suited to large displays like whiteboards. They describe the e-paper in the Journal of Applied Physics, from AIP Publishing.
Traditional ink and paper is convenient for both reading and writing. In e-paper development the writing feature has generally lagged behind. Handwriting-enabled displays mainly show up in the inexpensive, but feature-limited realm of children's toys, and in the high-end realm of touch-screen e-readers and smart ...
