It has access to the largest surface area of the body, alters drugs before they even enter the blood stream and could be a potent medicinal weapon… yet there is much we still don’t understand about the microbiome.
Here David Kirk and Ben Bradley tell us about their attempts to heal us from within
We are not alone. We are inhabited by hundreds of species of microbes, which represent millions of genes. Together, these microscopic organisms – bacteria, fungi, archaea and viruses – and their collective genomes make up the microbiome.
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In the gut, microbes break down otherwise indigestible dietary fibres and release nutrients, such as B-vitamins and short chain fatty acids, which can be absorbed by the intestines. They secrete other small molecules or peptides which interact with the body via the bloodstream and immune system. The majority of these have yet to be identified and characterised. In addition, commensal microbes deter opportunistic pathogens from invading the competitive niche of the intestinal tract.
LBPs are a recent concept and have their origins in a novel treatment for C. difficile infection: the faecal microbiota transplant… this is exactly what you think it is
The disruption of the microbiome, termed dysbiosis, is associated with an ever-growing list of conditions. Obesity and metabolic syndrome, for instance, are associated with a microbiome less diverse than that of a healthy individual. Inflammatory bowel disease (IBD) and colorectal cancer are associated with a decrease in butyrate-producing bacteria like Clostridia, and an increase in Enterobacteriaceae and Bacilli.
An air of scepticism comes with the phrase “associated”. Microbiome research is still a developing field, and the presence or absence of a single species or genus cannot be directly blamed for conditions like obesity or IBD in all patients. The complex interplay between host and microbiome depends as much on the host’s genetic susceptibility and environment as on the dysbiosis or lack of diversity in the microbiome. The million dollar question remains: What exactly constitutes a ‘healthy microbiome’?
A powerful tool
The microbiome is adaptive and changes in response to diet, environment and disease. It has become increasingly clear that many drugs interact with the microbiome, with some requiring microbiota derived enzymes for activation and others being rendered non-functional or even toxic via microbiota dependant conversion. As research in host-microbe interaction continues, more accurate relationships between the microbiome and human illness will be uncovered.
The gut microbiome presents an interesting medicinal target in itself. It interacts directly with one of the largest surface areas of the body. Therefore it has easy access to the bloodstream through diffusion of nutrients and small molecules, and via a mucosal layer rich in multiple cell types of the adaptive and innate immune systems. Due to the powerful delivering capacity of the gut, most microbial-based treatments in development aim to add to the microbiome rather than take away from it.
Microbial therapies using living organisms are known as live biotherapeutic products (LBPs). LBPs are a recent concept and have their origins in a novel treatment for C. difficile infection (CDI): the faecal microbiota transplant.
This is exactly what you think it is.
CDI occurs when the gut microbiome is wiped out by antibiotic use and becomes infected by C. difficile, an organism that is normally unable to compete against the natural microbiota. This illness may recur in spite of further antibiotic treatments, and can be fatal. The most effective treatment, in extreme cases, is a faecal transplant into the infected recipient. Transplanted microbes thrive and outcompete C. difficile, effectively reversing the infection in over 90% of cases. But due to the uncertainty of what constitutes a ‘healthy microbiome’, a faecal transplant cannot be considered a cure-all for dysbiosis-associated illness.
Daunting clinical trials
This “unknown” of host-microbe interaction sparked the need to develop defined microbiome therapies. Naturally, CDI was one of the first targets for a defined treatment. Several companies are developing and trialling defined cocktails of bacteria known to safely inhabit the gut with the goal of outcompeting C. difficile with Seres Therapeutics and Rebiotix entering phase 3 trials in 2018.
CHAIN Biotech is developing technology to deliver therapeutics to the gut microbiome using engineered Clostridium, a spore forming bacterium, and have a lead candidate targeting IBD. IBD is a collection of inflammatory diseases of the gut, commonly treated with steroid injections which cause numerous unpleasant side effects. Our approach is to deliver an LBP directly to the gut, where it can produce an anti-inflammatory in situ. We also make use of this species’ natural ability to produce spores, which survive the acidic environment of the stomach and germinates into therapeutic-producing cells only in the anaerobic environment of the lower intestine.
This elementary approach – adding one organism with a safe history of use in the human gut, and having it produce one novel product – minimizes the risk of disruption to the microbiome and delivers the treatment directly to the affected area. The next stages, taking LBPs to clinical trial, are daunting. A lot of unknowns exist around the human gut microbiome and these kinds of treatments. Few microbiome companies have LBPs in late-stage clinical trial, but those that do give hope to both patients and us that LBPs will someday heal us from within.
As published in Seres Therapeutics Press Release January 31, 2017
Findings suggest that both misdiagnosis of C. difficile recurrent infection in some patients, and dosing that may have been suboptimal in certain patients, contributed to the previously reported SER-109 Phase 2 study outcome –
FDA discussions are ongoing regarding a new, redesigned clinical study for SER-109
CAMBRIDGE, Mass., On January 31, 2017 —Seres Therapeutics Inc., a leading microbiome
therapeutics platform company, reported that it has completed in-depth analyses of the previously reported SER-109 Phase 2, eight-week clinical study data in patients with multiply recurrent Clostridium difficile infection.
The company also reported the full, 24-week SER-109 Phase 2 study results and open label extension study data.
“Since obtaining the unexpected SER-109 clinical study results last summer, we have undertaken a comprehensive assessment of the program to understand the reasons for the results,” said Roger J. Pomerantz, M.D., President, CEO and Chairman of Seres.
“We have now identified specific factors that we believe contributed to the Phase 2 results, including issues related to both the accurate diagnosis of C. difficile recurrent infection, and potential suboptimal dosing of certain subjects in the trial. The SER-109 analyses were recently shared with the FDA, and we are actively discussing the design of a new clinical trial for SER-109. There remains a compelling need for an effective, safe, and convenient FDA approved therapy for patients with recurrent C. difficile infection, and this investigation provides insights to guide further clinical development of SER-109.”
Investigation Summary: C. difficile Diagnosis: Analysis was conducted to evaluate both the role of C. difficile diagnostic testing in defining the correct SER-109 Phase 2 study entry population, and in the proper diagnosis of C. difficile recurrences during the study. In the Phase 2 study, 81% of study subjects (72 of 89 subjects) were enrolled based on polymerase chain reaction (PCR) based testing for C. difficile, as well as clinical evaluation. An important and increasingly well-appreciated limitation of PCR testing is that while a positive result indicates that C. difficile cytotoxin genes are present, a positive PCR test does not necessarily indicate thatthe organism is viable and producing disease causing cytotoxins, nor that C. difficile is the source of clinical symptoms.1
Two separate observations were made pertaining to the effects of discordant results from PCR and cytotoxin assay on the SER-109 trial. The qualifying stool samples evaluated for Phase 2 study entry were not available for retesting for cytotoxin, however, the company was able to retest the samples associated with patients entering the open label extension trial for the presence of the C. difficile cytotoxin and determined that only 44% of samples (15 of 31 subjects) that tested positive by PCR testing also tested positive based on C. difficile cytotoxin assay. These results suggest that a substantial proportion of patients who entered the SER-109 Phase 2 study may have been C. difficile carriers and, therefore, C. difficile infection may not have been the source of the clinical symptoms. In addition, data from this analysis suggest that the use of PCR to measure C. difficile may have overestimated study recurrences in both treatment arms of the Phase 2 trial, further complicating interpretation of study results. This was shown by reanalysis of samples with cytotoxin assay, from patients diagnosed as recurrent in the Phase 2 study. In this retesting, between one quarter andone half of presumed study recurrences may not have been true C. difficile infections leading to pathology.
From the analyses described above, the company believes that misdiagnoses may have occurred both in some patients entering the SER-109 trial, as well as for recurrences diagnosed during the trial.
The company performed an in-depth analysis to examine SER-109 biological activity in the Phase 2 trial, as measured by microbiome changes in patients and downstream biological effects in the gastrointestinal tract. Results demonstrated a statistically significant increase in the richness of commensal spore-forming bacterial species in patients treated with SER-109, as compared to those receiving placebo. These data demonstrate that SER-109 successfully engrafted and was biologically active in the Phase 2 study. In addition, among those patients with an increased prevalence of specific SER-109 associated bacterial species, a decreasedrate of high confidence recurrences (i.e., recurrences confirmed by C. difficile cytotoxin assay) was demonstrated.
The company also assessed whether the SER-109 dose impacted the degree of microbiome changes observed. All Phase 2 patients received 1 X 10 8 bacterial spores, whereas patients in the prior SER-109 Phase 1b open label study received doses ranging approximately 700-fold, from 3 X 107 to 2 X 109 spores. The company also performed high-resolution whole metagenomics sequencing of stool samples collected from patients in both the SER-109 Phase 1b, as well as the Phase 2 trial as part of this analysis. The analysis indicated that subjects in the open-label Phase 1b study who received a higher dose achieved a significantly greater increase in diversity of commensal spore-former bacteria by 1 week post-treatment, as compared to both Phase 1b and Phase 2 subjects treated with lower doses. These results suggest that the dose used in the SER-109 Phase 2 study may have been suboptimal in certain patients, and may have resulted in a less robust drug effect, contributing to decreased efficacy in Phase 2, as compared to the Phase 1b study.
Much of the SER-109 Phase 2 microbiome-related learnings are based on advancements in the computational analytics and higher resolution whole metagenomics sequencing techniques that Seres is pioneering, and several of these methods were developed after the SER-109 Phase 2 study was designed. Insights obtained from this work may also
benefit Seres’ broad preclinical and clinical microbiome development pipeline.
Analysis of SER-109 Phase 2 Study Clinical Drug Product
The company also conducted a thorough and detailed investigation of the potential impacts of manufacturing and formulation changes implemented in the Phase 2 study. No issues regarding product quality or formulation were identified which would have impacted the Phase 2 study results.
Summary of SER-109 24-Week and Open Label Extension Study Results
The full, 24-week Phase 2 study results continue to demonstrate that SER-109 was generally well tolerated. The most common adverse events associated with SER-109 included diarrhea, abdominal pain and flatulence. The Phase 2 study population represented older individuals, many in poor health, and a high rate of serious adverse events (SAEs) was reported in both study arms. A numerically higher rate of SAEs was observed in the SER-109 arm (15.0% versus 10.3% for placebo), however there was no detectable pattern in the SAEs observed, and none of these were considered to be SER-109 drug-related by the study investigators.
As expected with recurrent C. difficile infection, relatively few additional recurrences occurred beyond 8 weeks, and the 24-week data provides relatively little new information regarding efficacy. Based on 24-week data, five further patients recurred in the SER-109 arm, but three of the five recurrences (60%) were in patients who terminated the trial early, resulting in an imputed recurrence. In the placebo arm, one patient also terminated the trial early, resulting in an imputed recurrence. Early terminations, and loss of patients to follow-up, are common in the long safety follow-up portions of clinical trials.
Phase 2 study subjects who experienced a C. difficile recurrence had the option to enroll in an open label extension study, where they were treated with SER-109 and were followed for an additional 24 weeks. In total, 34 patients entered the open label extension study and 11 patients recurred during the initial 8-week study period, a 32% recurrence rate.
About Seres Therapeutics: Seres Therapeutics, Inc. is a leading microbiome therapeutics platform company developing a novel class of biological drugs that are designed to treat disease by restoring the function of a dysbiotic microbiome, where the natural state of bacterial diversity and function is imbalanced. The Phase 2 study of Seres’ program SER-109 has been completed in multiply recurrent C. difficile infection. Seres’ second clinical candidate, SER-287, is being evaluated in a Phase 1b study in patients with mild-to-moderate ulcerative colitis (UC). Seres is also developing SER-262, the first ever synthetic microbiome therapeutic candidate, in a Phase 1b study in patients with primary C. difficile infection. For more information, please visit http://www.serestherapeutics.com. Follow us on Twitter @SeresTx.
Forward-looking Statements: This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation statements regarding our SER-109 development plans, the timing, design, and potential results of a new clinical study for SER-109, the potential for a redesigned trial to provide different results, and the impact any analysis may have on clinical outcomes.
These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: we have incurred significant losses, are not currently profitable and may never become profitable; our need for additional funding, which may not be available; our limited operating history; the unpredictable nature of our early stage development efforts for marketable drugs; the unproven approach to therapeutic intervention of our microbiome therapeutics; the lengthy and expensive process of clinical drug development, which has an uncertain outcome; potential delays in enrollment of patients which could affect the receipt of necessary regulatory approvals; potential delays in regulatory approval, which would impact the ability to commercialize our product candidates and affect our ability to generate revenue; any fast track or Breakthrough Therapy designation may not lead to faster development, regulatory approval or marketing approval; our possible inability to receive orphan drug designation should we choose to seek it; our reliance on third parties to conduct our clinical trials and the potential for those third parties to not perform satisfactorily; our reliance on third parties to manufacture our product candidates, which may delay, prevent or impair our development and commercialization efforts; our lack of experience in manufacturing our product candidates; the potential failure of our product candidates to be accepted on the market by the medical community; our lack of experience selling, marketing and distributing products and our lack of internal capability to do so; failure to compete successfully against other drug companies; potential competition from biosimilars; failure to obtain marketing approval internationally; post-marketing restrictions or withdrawal from the market; anti-kickback, fraud, abuse, and other healthcare laws and regulations exposing us to potential criminal sanctions; recently enacted or future legislation; compliance with environmental, health, and safety laws and regulations; protection of our proprietary technology; protection of the confidentiality of our trade secrets; changes in United States patent law; potential lawsuits for infringement of third-party intellectual property; our patents being found invalid or unenforceable; compliance with patent regulations; claims challenging the inventorship or ownership of our patents and other intellectual property; claims asserting that we or our employees misappropriated a third-party’s intellectual property or otherwise claiming ownership of what we regard as our intellectual property; adequate protection of our trademarks; ability to attract and retain key executives; managing our growth could result in difficulties; risks associated with international operations; potential system failures; the price of our common stock may fluctuate substantially; our executive officers, directors, and principal stockholders have the ability to control all matters submitted to the stockholders; a significant portion of our total outstanding shares are eligible to be sold into the market; unfavorable or lacking analyst research or reports; and we are currently subject to securities class action litigation. These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC, on November 10, 2016 and our other reports filed with the SEC, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.
Polage, C. R., et al. (2015). Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era. JAMA Internal Medicine, 175(11), 1792–1801.
IR or PR Contact:
Carlo Tanzi, Ph.D., Seres Therapeutics, 617-203-3467
Head of Investor Relations and Corporate Communications
The microbiome of patients admitted to the intensive care unit (ICU) at a hospital differs dramatically from that of healthy patients, according to a new study published in mSphere.
Researchers analyzing microbial taxa in ICU patients’ guts, mouth and skin reported finding dysbiosis, or a bacterial imbalance, that worsened during a patient’s stay in the hospital. Compared to healthy people, ICU patients had depleted populations of commensal, health-promoting microbes and higher counts of bacterial taxa with pathogenic strains – leaving patients vulnerable to hospital-acquired infections that may lead to sepsis, organ failure and potentially death.
What is dysbiosis? Pathogens, antibiotic use, diet, inflammation, and other forces can cause dysbiosis, a disruption in these microbial ecosystems that can lead to or perpetuate disease (1)
What makes a gut microbiome healthy or not remains poorly defined in the field. Nonetheless, researchers suspect that critical illness requiring a stay in the ICU is associated with the the loss of bacteria that help keep a person healthy. The new study, which prospectively monitored and tracked changes in bacterial makeup, delivers evidence for that hypothesis.
“The results were what we feared them to be,” says study leader Paul Wischmeyer, an anesthesiologist at the University of Colorado School of Medicine. “We saw a massive depletion of normal, health-promoting species.”
Wischmeyer, who will move to Duke University in the fall, runs a lab that focuses on nutrition-related interventions to improve outcomes for critically ill patients.
He notes that treatments used in the ICU – including courses of powerful antibiotics, medicines to sustain blood pressure, and lack of nutrition – can reduce the population of known healthy bacteria. An understanding of how those changes affect patient outcomes could guide the development of targeted interventions to restore bacterial balance, which in turn could reduce the risk of infection by dangerous pathogens.
Previous studies have tracked microbiome changes in individual or small numbers of critically ill patients, but Wischmeyer and his collaborators analyzed skin, stool, and oral samples from 115 ICU patients across four hospitals in the United States and Canada. They analyzed bacterial populations in the samples twice – once 48 hours after admission, and again after 10 days in the ICU (or when the patient was discharged). They also recorded what the patients ate, what treatments patients received, and what infections patients incurred.
The researchers compared their data to data collected from a healthy subset of people who participated in the American Gut project dataset. (American Gut is a crowd-sourced project aimed at characterizing the human microbiome by the Rob Knight Lab at the University of California San Diego.) They reported that samples from ICU patients showed lower levels of Firmicutes and Bacteroidetes bacteria, two of the largest groups of microbes in the gut, and higher abundances of Proteobacteria, which include many pathogens.
Wischmeyer was surprised by how quickly the microbiome changed in the patients. “We saw the rapid rise of organisms clearly associated with disease,” he says. “In some cases, those organisms became 95 percent of the entire gut flora – all made up of one pathogenic taxa – within days of admission to the ICU. That was really striking.” Notably, the researchers reported that some of the patient microbiomes, even at the time of admission, resembled the microbiomes of corpses. “That happened in more people than we would like to have seen,” he says.
Wischmeyer suggests the microbiome could be tracked like other vital signs and could potentially be used to identify patient problems and risks before they become symptomatic. In addition, now that researchers have begun to understand how the microbiome changes in the ICU, Wischmeyer says the next step is to use the data to identify therapies – perhaps including probiotics – to restore a healthy bacterial balance to patients.
Everyone who collaborated on the project – including dietitians, pharmacists, statisticians, critical care physicians, and computer scientists – participated on a largely voluntary basis without significant funding to explore the role of the microbiome in ICU medicine, says Wischmeyer.
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As Season II concludes, we wish to take this opportunity to sincerely thank each
and every guest for taking time out of their
busy schedule and joining us on Tuesday’s at
10:00a Pacific Time / 1:00p Eastern Time over the past seven months.
C. diff. Spores and More Global Broadcasting Network will be taking a break and will return to live broadcasting on January 17th, 2017 with the Centers for Disease Control and Prevention (CDC) leading the way with our guest Dr. Katherine Fleming-Dutra, Medical Officer, CDC’s Office of Antibiotic Stewardship.
A Prescription for Over-Prescribing: The Key to Fighting
Dr. Fleming-Dutra is a medical epidemiologist with the Office of Antibiotic Stewardship in the Division of Healthcare Quality Promotion at the Centers Disease Control and Prevention (CDC).
Dr. Fleming-Dutra is a pediatrician and pediatric emergency medicine physician and has focused on infectious diseases epidemiology and antibiotic stewardship in the outpatient setting in her career at CDC.
Join Dr. Fleming-Dutra as she discusses a recent study published by the Journal of the American Medical Association, was released showing that at least 30 percent of all prescriptions written in doctors’ offices and emergency rooms are completely unnecessary. So how do we use these alarming results to transform the culture of over-prescribing Dr. Katherine Fleming-Dutra, M.D., will:
Give a detailed explanation of the study results, and provide an in-depth review of specific findings;
Highlight what CDC is doing to promote antibiotic stewardship across healthcare settings, and
Identify what clinicians, other health care professionals, and patients can do to improve antibiotic prescribing, therefore fighting antibiotic resistance.
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Hard Facts: Deaths and illnesses are much higher than reports have shown. Nearly half a million Americans suffered from Clostridium difficile (C. diff.) infections in a single year according to a study released today, February 25, 2015, by the Centers for Disease Control and Prevention (CDC).
• More than 100,000 of these infections developed among residents of U.S. nursing homes.
Approximately 29,000 patients died within 30 days of the initial diagnosis of a C. diff. infection. Of these 29,000 – 15,000 deaths were estimated to be directly related to a C. diff. infection. Therefore; C. diff. is an important cause of infectious disease death in the U.S.
Previous studies indicate that C. diff. has become the most common microbial cause of Healthcare-Associated Infections found in U.S. hospitals driving up costs to $4.8 billion each year in excess health care costs in acute care facilities alone. Approximately
two-thirds of C. diff. infections were found to be associated with an inpatient stay in a health care facility, only 24% of the total cases occurred in patients while they were hospitalized. The study also revealed that almost as many cases occurred in nursing homes as in hospitals and the remainder of individuals acquired the
Healthcare-Associated infection, C. diff., recently discharged from a health care facility.
This new study finds that 1 out of every 5 patients with the Healthcare-Associated Infection (HAI), C. diff., experience a recurrence of the infection and 1 out of every 9 patients over the age of 65 diagnosed with a HAI – C. diff. infection died within 30 days of being diagnosed. Older Americans are quite vulnerable to this life-threatening diarrhea infection. The CDC study also found that women and Caucasian individuals are at an increased risk of acquiring a C. diff. infection. The CDC Director, Dr. Tom Frieden, MD, MPH said, “C. difficile infections cause immense suffering and death for thousands of Americans each year.” “These infections can be prevented by improving antibiotic prescribing and by improving infection control in the health care system. CDC hopes to ramp up prevention of this deadly infection by supporting State Antibiotic Resistance Prevention Programs in all 50 states.”
“This does not include the number of C. diff. infections taking place and being treated in other countries.” “The C Diff Foundation supports hundreds of communities by sharing the Foundation’s mission and raising C. diff. awareness to healthcare professionals, individuals, patients, families, and communities working towards a shared goal ~ witnessing a reduction of newly diagnosed C. diff. cases by 2020 .” ” The C Diff Foundation volunteer Advocates are greatly appreciated and continue to create positive changes by sharing their time aiding in the success of our mission “Raising C. diff. awareness ™” worldwide.
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Through their interviews, the C Diff Foundation mission will connect, educate, and empower listeners worldwide.
Questions received through the show page portal will be reviewed and addressed by the show’s Medical Correspondent, Dr. Fred Zar, MD, FACP, Dr. Fred Zar is a Professor of Clinical Medicine, Vice Head for Education in the Department of Medicine, and Program Director of the Internal Medicine Residency at the University of Illinois at Chicago. Over the last two decades he has been a pioneer in the study of the treatment of Clostridium difficile disease and the need to stratify patients by disease severity.
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Every year, about half a million patients are infected by Clostridium difficile, an otherwise harmless bacterium that can multiply out of control when the use of antibiotics upsets the balance of microorganisms in the gut. In 2011, about 15,000 deaths were directly attributable to the infection, according to a recent study by the federal Centers for Disease Control and Prevention (CDC).
Current probiotic treatments, which promote the growth of helpful bacteria, have been ineffective against the infection, also known as C. diff.
But work being done at U.Va.’s Division of Infectious Diseases and International Health could lead to a new treatment by the end of the calendar year, according to Dr. Bill Petri, chief of the division. That’s an unusually optimistic estimate in medical research, where scientific breakthroughs predate new treatments by several years.
“Some of these advanced probiotics are actually being tested today in the clinic for their role,” Petri said. “We’re actually participating in advanced clinical trials at U.Va.”
Immunologist Erica L. Buonomo was the driving force behind the new discovery, Petri said, which has to do with the role of white blood cells in protecting against C. diff.
Buonomo found that a particular type of white blood cells, called eosinophils, act as a barrier against the infection, which breaks down the lining of the gut. These eosinophils are recruited by a protein called IL-25. A serious C. diff infection kills eosinophils, allowing the bacteria to enter the gut.
The researchers found that gut bacteria stimulate the production of IL-25, so the right probiotic could help with the production of protective eosinophils.
“We identified a pathway in the immune response that reduces the severity of an infection,” Buonomo said. “When we activate this pathway, we find mice are a lot less sick.”
The discovery would be especially helpful for elderly patients, who are most at risk. It also could have larger implications in the world of microbiology.
Eosinophils are best known for their role in allergic reactions and asthma attacks, when a high number of eosinophils cause inflammation.
The function of these cells was not entirely clear before Buonomo’s discovery. She believes this knowledge could help doctors fight other types of gastrointestinal disorders, such as irritable bowel syndrome.