Thursday, November 09, 2023

Found at last: Bizarre, egg-laying mammal finally rediscovered after 60 years


Reports and Proceedings

UNIVERSITY OF OXFORD

Attenborough's long-beaked echidna 1 

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ATTENBOROUGH'S LONG-BEAKED ECHIDNA, PHOTOGRAPHED BY A CAMERA TRAP. CREDIT: EXPEDITION CYCLOPS.

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CREDIT: EXPEDITION CYCLOP




  • A long-beaked echidna named after Sir David Attenborough and last seen by scientists in 1961 has been photographed for the first time in an Indonesian tropical forest.
  • An international team of researchers worked with local communities to deploy over 80 camera traps to film the elusive animal.
  • Besides rediscovering the echidna, the team uncovered a wealth of species completely new to science, including beetles, spiders, and a remarkable tree-dwelling shrimp.
  • A wide range of images and video footage from the expedition are available (see link below).

More than sixty years after it was last recorded, an expedition team has rediscovered an iconic, egg-laying mammal in one of the most unexplored regions of the world. Attenborough's long-beaked echidna, named after famed broadcaster Sir David Attenborough, was captured for the first time in photos and video footage using remote trail cameras set up in the Cyclops Mountains of Indonesia's Papua Province.

Alongside the echidna's rediscovery, the expedition – a partnership between the University of Oxford, Indonesian NGO Yayasan Pelayanan Papua Nenda (YAPPENDA), Cenderawasih University (UNCEN), Papua BBKSDA, and the National Research and Innovation Agency of Indonesia (BRIN), Re:Wild – made many other remarkable finds. These included Mayr's honeyeater, a bird lost to science since 2008; an entirely new genus of tree-dwelling shrimp; countless new species of insects; and a previously unknown cave system. This was despite the difficulties posed by extremely inhospitable terrain, including venomous animals, blood-sucking leeches, malaria, earthquakes, and exhausting heat.

One of the world's most unusual mammals finally caught on film

Recorded by science only once in 1961, Attenborough's long-beaked echidna is a monotreme: an evolutionarily distinct group of egg-laying mammals that includes the platypus. This echidna species is so special because it is one of only five remaining species of monotremes, the sole guardians of this remarkable branch of the tree of life. Echidnas are notoriously difficult to find since they are nocturnal, live in burrows, and tend to be very shy. Attenborough's long-beaked echidna has never been recorded anywhere outside the Cyclops Mountains, and is currently classified as Critically Endangered on the IUCN Red List of Threatened Species

To give themselves the best chance of finding one, the team deployed over 80 trail cameras, making multiple ascents of the mountains, and climbing more than 11,000 meters (more than the height of Everest) in the process. For almost the entire four weeks that the team spent in the forest, the cameras recorded no sign of the echidna. On the last day, with the last images on the final memory card, the team obtained their shots of the elusive mammal – the first ever photographs of Attenborough's echidna. The identification of the species was later confirmed by Professor Kristofer Helgen, mammalogist and chief scientist and director of the Australian Museum Research Institute (AMRI).

Dr James Kempton, a biologist from the University of Oxford who conceived of and led the expedition, said: ‘Attenborough's long-beaked echidna has the spines of a hedgehog, the snout of an anteater, and the feet of a mole. Because of its hybrid appearance, it shares its name with a creature of Greek mythology that is half human, half serpent. The reason it appears so unlike other mammals is because it is a member of the monotremes – an egg-laying group that separated from the rest of the mammal tree-of-life about 200 million years ago.’

‘The discovery is the result of a lot of hard work and over three and a half years of planning,’ he added. ‘A key reason why we succeeded is because, with the help of YAPPENDA, we have spent years building a relationship with the community of Yongsu Sapari, a village on the north coast of the Cyclops Mountains. The trust between us was the bedrock of our success because they shared with us the knowledge to navigate these treacherous mountains, and even allowed us to research on lands that have never before felt the tread of human feet.’

Attenborough's long-beaked echidna, photographed by a camera trap. Credit: Expedition Cyclops

Cenderawasih University (UNCEN) student and team member Gison Morib setting up one of the eighty camera traps which were placed in the Cyclops Mountains in order to capture images of Attenborough's long-beaked echidna for the first time. Credit: Expedition Cyclops.

Expedition leader Dr James Kempton (University of Oxford) collecting specimens after ascending the slopes of the Cyclops Mountains. Credit: Expedition Cyclops.

A temporary expedition campsite on the northern slopes of the Cyclops Mountains. Members of the Yongsu Sapari community helped prepare paths and campsites for the expedition to conduct their research. Credit: Expedition Cyclops.

CREDIT

Expedition Cyclops.


A treasure trove of discoveries

Alongside searching for the echidna, the expedition carried out the first comprehensive assessment of invertebrate, reptile, amphibian, and mammal life in the Cyclops Mountains. With the support of local guides in the expedition team, the scientists were able to create makeshift labs in the heart of the jungle with benches and desks made from forest branches and vines.

By combining scientific techniques with the Papuan team members’ experience and knowledge of the forest, the team made a wealth of new discoveries. These included several dozens of insect species completely new to science and the rediscovery of Mayr's honeyeater (Ptiloprora mayri), a bird lost to science since 2008 and named after famed evolutionary biologist Ernst Mayr.     

An extraordinary finding was an entirely new genus of ground and tree-dwelling shrimp. ‘We were quite shocked to discover this shrimp in the heart of the forest, because it is a remarkable departure from the typical seaside habitat for these animals,’ said Dr Leonidas-Romanos Davranoglou (a Leverhulme Trust Postdoctoral Fellow at the Oxford University Museum of Natural History), lead entomologist for the expedition. ‘We believe that the high level of rainfall in the Cyclops Mountains means the humidity is great enough for these creatures to live entirely on land.’

The team also revealed a treasure trove of underground species, including blind spiders, blind harvestman, and a whip scorpion, all new to science, in a previously unexplored cave system. This astonishing discovery was made on one of the sacred peaks above Yongsu Sapari where the team had been given special permission to do research. People rarely tread here, and the striking cave system was chanced upon when one team member fell through a moss-covered entrance.


A new species of terrestial shrimp, found in the soil and in the trees of the Cyclops Mountains. This shrimp belongs to a lineage that is normally found on the seashore, and it was an enormous surpise to the expedition team when it was discovered living hundreds of meters high up on th slopes of the mountains. Credit: Expedition Cyclops. 

CREDIT

Expedition Cyclops.

'A beautiful but dangerous land'

Extremely challenging and, at times, life-threatening conditions were at the background of these discoveries. During one of the trips to the cave system, a sudden earthquake forced the team to evacuate. Dr Davranoglou broke his arm in two places, one member contracted malaria, and another had a leech attached to his eye for a day and a half before it was finally removed at a hospital. Throughout the expedition, members were beset by biting mosquitoes and ticks, and faced constant danger from venomous snakes and spiders. Making any progress through the jungle was a slow and exhausting process, with the team sometimes having to cut paths where no humans had ever been before.

‘Though some might describe the Cyclops as a “Green Hell”, I think the landscape is magical, at once enchanting and dangerous, like something out of a Tolkien book’ said Dr Kempton. ‘In this environment, the camaraderie between the expedition members was fantastic, with everyone helping to keep up morale. In the evening, we exchanged stories around the fire, all the while surrounded by the hoots and peeps of frogs.’

An enduring legacy

Rediscovering the echidna is only the beginning of the expedition's mission. Attenborough's long-beaked echidna is the flagship animal of the Cyclops Mountains and a symbol of its extraordinary biodiversity. The team hope that its rediscovery will help bring attention to the conservation needs of the Cyclops, and Indonesian New Guinea more generally, and they are committed to supporting long-term monitoring of the echidna. Key to this work is NGO YAPPENDA, whose mission is to protect the natural environment of Indonesian New Guinea through empowerment of Indigenous Papuans. As part of the expedition team, members of YAPPENDA helped train six students from UNCEN in biodiversity surveys and camera trapping during the expedition.

Dr Davranoglou said: ‘Tropical rainforests are among the most important and most threatened terrestrial ecosystems. It is our duty to support our colleagues on the frontline through exchanging knowledge, skills, and equipment.’

With the team having only sorted a fraction of the material collected on the expedition, they expect that the coming months will yield even more new species. The intention is to name many of these after the Papuan members of the expedition.

Besides animal specimens, the team also collected over 75 kg of rock samples for geological analysis, which was led by the expedition's chief geologist, Max Webb, from Royal Holloway University, London. These could help answer many questions about how and when the Cyclops Mountains originally formed. The mountains are believed to have formed when an island arc in the Pacific Ocean collided with the New Guinea mainland about 10 million years ago. Combined with the biological findings, this geological work will help the team understand how the extraordinary biodiversity of the Cyclops came to be.

Notes for editors:

For media enquiries and interview requests, contact James Kempton: james.kempton@biology.ox.ac.uk +44 7954683094

A press pack of images and video footage (with captions) is available at: https://drive.google.com/drive/folders/1VV7FRWwf-B1kMQ2ClEjU6rR-y3bRgzr2 Images/video can be used in articles if credited.

More information about the expedition can be found at https://www.expeditioncyclops.co.uk/

About Attenborough's long-beaked echidna:

  • Attenborough's long-beaked echidna, Zaglossus attenboroughi, is not known to live outside the Cyclops Mountains and biologists still have many unanswered questions about its habitat and ecology.
  • Attenborough's long-beaked echidna is an EDGE species: a threatened species that has few close relatives on the evolutionary tree of life. They have evolved independently of other mammals for about 200 million years.
  • The echidna has cultural significance for the people of Yongsu Sapari, who have lived on the northern slopes of the Cyclops Mountains for eighteen generations. When there is a conflict within the community, rather than fighting, there is a tradition that one party goes up into the Cyclops to search for an echidna while the other party goes to the ocean to find a marlin. Both creatures were so difficult to find that it would often take decades or a whole generation to locate them, but, once found, the animals symbolized the end of the conflict and a return to harmonious relationships in the village.
  • The echidna has only been scientifically recorded once, when it was discovered by Pieter van Royen – a Dutch botanist – in 1961. Since then it has only been known from reports of sightings by the Yongsu Sapari community, and indirect signs during pre-expedition work in 2022. These signs, also observed during the expedition, included 'nose pokes,' holes in the ground left by echidnas after using their long, slightly curved snouts to probe for underground invertebrates.  

About the expedition:

  • The expedition was first proposed in 2019 by James Kempton.
  • Academics who collaborated closely on the expedition include Dr James Kempton (University of Oxford), Dr Leonidas-Romanos Davranoglou (Oxford University Museum of Natural History), Madeleine Foote (University of Oxford), Dr Andrew Tilker (Re:wild, Leibniz Institute for Zoo and Wildlife Research), Dr Attila Balázs (Mendel University) and Dr Max Webb (Royal Holloway, University of London).
  • Cenderawasih University (UNCEN) team members and partners include Dr Suriani Surbakti, Gison Morib and Heron Yando.
  • Team members and collaborators from Indonesian NGO Yayasan Pelayanan Papua Nenda (YAPPENDA) include co-founders Iain and Malcolm Kobak, and Yali Kobak, Sampari Kobak, Ezra Daniel, Ruben Penggu, Melias Heluka, Yuanis Yalak and Sili Yalak.
  • The team obtained permits from Papua BBKSDA and BRIN. They were also given permission from the community of Yongsu Sapari to conduct research and collect specimens on their land during the expedition.
  • This rediscovery was made possible in part by the generous support of Merton College Oxford, the Royal Geographical Society, the Scientific Exploration Society, Re:wild, Royal Holloway University, the University of Oxford, Reconyx, and private donations from Derek Williams, Chris Peri, and other generous individuals.

About the Cyclops Mountains:

  • The Cyclops Mountains are one of the most inhospitable regions in the world, being rugged, steep, and dangerous, and ranging from sea level to 1,970 metres. They are dominated by two main peaks – Gunung Rara and Gunung Dafonsoro. When sailing ten leagues from the range's northern coastline in 1768, Baron Louis de Bougainville noted 'les deux cyclopes', from which the mountains bear their name.
  • The Cyclops Mountains are a Key Biodiversity Area, meaning that they are critical to the persistence of biodiversity and to the overall health of the planet.
  • The community of Yongsu Sapari have lived in the region for eighteen generations and hold the land as sacred. They believe it is stewarded by a female spirit who can take the form of a tree-kangaroo.

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the eighth year running, and ​number 3 in the QS World Rankings 2024. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer.

Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions.

Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 300 new companies since 1988. Over a third of these companies have been created in the past five years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing £15.7 billion to the UK economy in 2018/19, and supports more than 28,000 full time jobs.

 

Understanding the dynamic behavior of rubber materials


Researchers present a novel experimental system for simultaneous measurement of dynamic mechanical properties and X-ray computed tomography


Peer-Reviewed Publication

WASEDA UNIVERSITY

Experimental setup for the simultaneous measurement of dynamic mechanical properties and dynamic micro X-ray CT. 

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THIS NOVEL SYSTEM CAN ELUCIDATE THE MICROSTRUCTURE OF RUBBER-LIKE MATERIALS UNDER DYNAMIC CONDITIONS, ENHANCING OUR UNDERSTANDING OF THEIR DYNAMIC BEHAVIOR AND PAVING THE WAY FOR IMPROVED NOVEL MATERIALS.

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CREDIT: MASAMI MATSUBARA FROM WASEDA UNIVERSITY




Rubber-like materials, commonly used in dampeners, possess a unique property known as dynamic viscoelasticity, enabling them to convert mechanical energy from vibrations into heat while exhibiting spring-like and flow-like behaviors simultaneously. Customization of these materials is possible by blending them with compounds of specific molecular structures, depending on the dynamic viscosity requirements.

However, the underlying mechanisms behind the distinct mechanical properties of these materials remain unclear. A primary reason for this knowledge gap has been the absence of a comprehensive system capable of simultaneously measuring the mechanical properties and observing the microstructural dynamics of these materials. While X-ray computed tomography (CT) has recently emerged as a promising option for a non-destructive inspection of the internal structure of materials down to nano-scale resolutions, it is not suited for observation under dynamic conditions.

Against this backdrop, a team of researchers, led by Associate Professor (tenure-track) Masami Matsubara from the School of Creative Science and Engineering at the Faculty of Engineering at Waseda University in Japan, has now developed an innovative system that can conduct dynamic mechanical analysis and dynamic micro X-ray CT imaging simultaneously. Their study was made available online on October 19, 2023 and will be published in Volume 205 of the journal Mechanical Systems and Signal Processing on December 15, 2023.

"By integrating X-ray CT imaging performed at the large synchrotron radiation facility Spring-8(BL20XU) and mechanical analysis under dynamic conditions, we can elucidate the relationship between a material's internal structure, its dynamic behavior, and its damping properties," explains Dr. Matsubara. At the core of this novel system is the dynamic micro X-ray CT and a specially designed compact shaker developed by the team that is capable of precise adjustment of vibration amplitude and frequency.

The team utilized this innovative system to investigate the distinctions between styrene-butadiene rubber (SBR) and natural rubber (NR), as well as to explore how the shape and size of ZnO particles influence the dynamic behavior of SBR composites.

The researchers conducted dynamic micro X-ray CT scans on these materials, rotating them during imaging while simultaneously subjecting them to vibrations from the shaker. They then developed histograms of local strain amplitudes by utilizing the local strains extracted from the 3D reconstructed images of the materials’ internal structures. These histograms, in conjunction with the materials' loss factor, a measure of the inherent damping of a material, were analyzed to understand their dynamic behavior.

When comparing materials SBR and NR, which have significantly different loss factors, the team found no discernible differences between their local strain amplitude histograms. However, the histograms displayed wider strain distributions in the presence of composite particles like ZnO. This suggests that strain within these materials is non-uniform and depends on the shape and size of the particles, which may have masked any changes from the addition of the particles.

This technology can allow us to study the microstructure of rubber and rubber-like materials under dynamic conditions and can result in the development of fuel-efficient rubber tires or gloves that do not deteriorate. Moreover, this technology can also enable the dynamic X-ray CT imaging of living organs that repeatedly deform, such as the heart, and can even pave the way for the development of artificial organs,” says Dr. Matsubara, highlighting the importance of this study.

Overall, this breakthrough technology has the potential to advance the understanding of the microstructure of viscoelastic materials, likely opening the doors for the development of novel materials with improved properties.

 

***

 

Reference

DOI: https://doi.org/10.1016/j.ymssp.2023.110875

Authors: Masami Matsubara1, Ryo Takara2, Taichi Komatsu2, Shogo Furuta2, Khoo Pei Loon2, Masakazu Kobayashi2, Hitomu Mushiaki3, Kentaro Uesugi4, Shozo Kawamura2, and Daiki Tajiri2

Affiliations      

1Department of Modern Mechanical Engineering, Waseda University

2Department of Mechanical Engineering, Toyohashi University of Technology

3Hyogo Prefectural Institute of Technology

4Japan Synchrotron Radiation Research Institute

 

 

About Waseda University

Located in the heart of Tokyo, Waseda University is a leading private research university that has long been dedicated to academic excellence, innovative research, and civic engagement at both the local and global levels since 1882. The University has produced many changemakers in its history, including nine prime ministers and many leaders in business, science and technology, literature, sports, and film. Waseda has strong collaborations with overseas research institutions and is committed to advancing cutting-edge research and developing leaders who can contribute to the resolution of complex, global social issues. The University has set a target of achieving a zero-carbon campus by 2032, in line with the Sustainable Development Goals (SDGs) adopted by the United Nations in 2015. 

To learn more about Waseda University, visit https://www.waseda.jp/top/en

 

About Associate Professor Masami Matsubara

Masami Matsubara is an Associate Professor (tenure-track) at the School of Creative Science and Engineering of the Faculty of Science and Engineering at Waseda University, Japan. He earned his Ph.D. from Doshisha University. His research focuses on the mechanics of materials, mechatronics, and dynamic modelling. He has recently worked on vibration reduction methods and dynamic design for large-scale numerical analysis models and detailed design and experimental methods for component and unit testing. He is a member of the Japan Society of Mechanical Engineers (JSME) and SAE International. He received the JSME Medal for Outstanding Paper in 2014, 2020, and 2022.

 

Allergic responses to common foods could significantly increase risk of heart disease, cardiovascular death


Antibodies to allergens such as dairy, peanuts may up risk even for people without obvious food allergies, surprising new research reveals

Peer-Reviewed Publication

UNIVERSITY OF VIRGINIA HEALTH SYSTEM

Allergic responses to common foods could sharply increase risk of heart disease, cardiovascular death 

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UVA HEALTH'S JEFFREY WILSON, MD, PHD, AND COLLABORATORS HAVE DISCOVERED AN IMPORTANT AND PREVIOUSLY UNAPPRECIATED CAUSE OF HEART DISEASE: SENSITIVITY TO COMMON FOOD ALLERGENS SUCH AS DAIRY AND PEANUTS. THIS CAN AFFECT BOTH PEOPLE WITH FOOD ALLERGIES AND THOSE WITH NO SYMPTOMS.

 

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CREDIT: UVA HEALTH





Sensitivity to common food allergens such as dairy and peanuts could be an important and previously unappreciated cause of heart disease, new research suggests – and the increased risk for cardiovascular death includes people without obvious food allergies.

That increased risk could be comparable to – or exceed – the risks posed by smoking, as well as diabetes and rheumatoid arthritis, the researchers report.

UVA Health scientists and their collaborators looked at thousands of adults over time and found that people who produced antibodies in response to dairy and other foods were at elevated risk of cardiovascular-related death. This was true even when traditional risk factors for heart disease, such as smoking, high blood pressure and diabetes, were taken into account. The strongest link was for cow’s milk, but other allergens such as peanut and shrimp were also significant. 

The troubling finding represents the first time that “IgE” antibodies to common foods have been linked to increased risk of cardiovascular mortality, the researchers report. The findings do not conclusively prove that food antibodies are causing the increased risk, but the work builds on prior studies connecting allergic inflammation and heart disease.

Approximately 15% of adults produce IgE antibodies in response to cow’s milk, peanuts and other foods. While these antibodies cause some people to have severe food allergies, many adults who make these antibodies have no obvious food allergy. The new research found that the strongest link with cardiovascular death was in people who had the antibodies but continued to consume the food regularly – suggesting they didn’t have a severe food allergy.      

“What we looked at here was the presence of IgE antibodies to food that were detected in blood samples,” said researcher Jeffrey Wilson, M.D., Ph.D., an allergy and immunology expert at the University of Virginia School of Medicine. “We don’t think most of these subjects actually had overt food allergy, thus our story is more about an otherwise silent immune response to food. While these responses may not be strong enough to cause acute allergic reactions to food, they might nonetheless cause inflammation and over time lead to problems like heart disease.”

Unexpected Food Allergy Findings

The researchers were inspired to investigate the possibility that common food allergies could be harming the heart after members of the UVA team previously linked an unusual form of food allergy spread by ticks to heart disease. That allergy, first identified by UVA’s Thomas Platts-Mills, M.D., Ph.D., is transmitted by the bite of the lone star tick, found throughout much of the country.

The allergy – commonly if inaccurately called the “red meat allergy” – sensitizes people to a particular sugar, alpha-gal, found in mammalian meat. The symptomatic form of the allergy, known as “alpha-gal syndrome,” can cause hives, upset stomach and breathing difficulties – even potentially deadly anaphylaxis – three to eight hours after affected people eat beef or pork. (Poultry and fish don’t contain the sugar, so they don’t trigger a reaction.)

To see if other food allergies could be affecting the heart, a team including Wilson, Platts-Mills and collaborators from UVA, as well as Corinne Keet, M.D., Ph.D., of the University of North Carolina, reviewed data collected from 5,374 participants in the National Health and Examination Survey (NHANES) and the Wake Forest site of the Multi-Ethnic Study of Atherosclerosis (MESA). Of those people, 285 had died from cardiovascular causes.

Among the NHANES participants, IgE antibodies to at least one food was associated with a significantly higher risk of cardiovascular death, the researchers found. This was particularly true for people sensitive to milk, a finding that held true among the MESA participants as well. Additional analysis also identified peanut and shrimp sensitization as significant risk factors for cardiovascular death in those individuals who routinely ate them.

“We previously noted a link between allergic antibodies to the alpha-gal red meat allergen and heart disease,” Wilson explained. “That finding has been supported by a larger study in Australia, but the current paper suggests that a link between allergic antibodies to food allergens and heart disease is not limited to alpha-gal. In some ways, this is a surprising finding. On the other hand, we are not aware that anyone has looked before.”

Allergies and the Heart

While this is the first time that allergic antibodies to common foods have been linked to cardiovascular mortality, other allergic conditions – such as asthma and the itchy rash known as eczema or atopic dermatitis – previously have been identified as risk factors for cardiovascular disease.

The researchers speculate that allergic antibodies to food may be affecting the heart by leading to the activation of specialized cells, called mast cells. Mast cells in the skin and gut are known to contribute to classic allergic reactions, but they are also found in the cardiac blood vessels and heart tissue. Persistent activation of mast cells could drive inflammation, contributing to harmful plaque buildup that can cause heart attacks or other heart damage, the researchers believe.

The scientists underscore, however, that this is not yet certain. It’s possible that other genetic or environmental factors could be at play. It’s even possible that cardiovascular disease could increase the risk for food sensitization – meaning that heart disease could up your risk for food allergies, rather than the other way round – though the new results suggest this is unlikely.

The researchers are calling for further studies to better understand the implications of their finding before recommending any changes in how doctors treat or manage food allergies.

“This work raises the possibility that in the future a blood test could help provide personalized information about a heart-healthy diet,” Wilson said. “Though before that could be recommended, we still have a lot of work to do understand these findings.”

Findings Published

The researchers have published their findings in the leading allergy journal, the Journal of Allergy and Clinical Immunology. The research team consisted of Keet, Emily McGowan, David Jacobs, Wendy Post, Nathan Richards,

Lisa Workman, Platts-Mills, Ani Manichaikul and Wilson. Wilson and Platts-Mills have received support from Thermo-Fisher/Phadia; a full list of the authors’ disclosures is included in the paper.

The research was supported by the National Institutes of Health’s National Institute of Allergy and Infectious Disease, grants 5U01AI125290, R37-AI20565 and R21AI151497; and by an AAAAI Foundation Faculty Development Award. A list of the financial backers of the MESA trial is available in the paper.

To keep up with the latest medical research news from UVA, subscribe to the Making of Medicine blog at http://makingofmedicine.virginia.edu.

Antibodies to cow’s milk linked to increased risk of cardiovascular death


Analyses led by Corinne Keet, MD, PhD, at the University of North Carolina School of Medicine, of two longitudinal studies reveal how an increased level of an antibody called immunoglobin (IgE) to cow’s milk is associated to cardiovascular-related death


Peer-Reviewed Publication

UNIVERSITY OF NORTH CAROLINA HEALTH CARE

Corinne Keet, MD, PhD 

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CORINNE KEET, MD, PHD, PEDIATRIC ALLERGY AND IMMUNOLOGY PROFESSOR IN THE UNC DEPARTMENT OF PEDIATRICS

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CREDIT: UNC SCHOOL OF MEDICINE




Sensitivity to common food allergens such as cow’s milk and peanuts could be an important and previously unappreciated cause of heart disease, new research suggests – and the increased risk for cardiovascular death includes people without obvious food allergies.

In a paper published in The Journal of Allergy and Clinical Immunology that describes analyses led by Corinne Keet, M.D., Ph.D., pediatric allergy and immunology professor in the UNC Department of Pediatrics of two longitudinal studies, the authors show that the people who produced IgE antibodies to cow’s milk and other foods were at significantly increased risk of cardiovascular mortality. This was true even when traditional risk factors for heart disease, such as smoking, high blood pressure, and diabetes were accounted for. The strongest link was for cow’s milk, but IgE to other allergens such as peanut and shrimp were also significant among those who eat the foods.

This troubling finding represents the first time that IgE antibodies to common foods have been linked to increased risk of cardiovascular mortality, the researchers report. The findings do not conclusively prove that food antibodies are causing the increased risk, but the work builds on previous studies connecting allergic inflammation and heart disease.

“People who had an antibody called IgE to foods that they regularly eat seemed to be at increased risk for dying from heart disease,” said Keet, who is the corresponding author of the paper. “We were surprised by these findings because it is very common to have IgE to foods (about 15% of American adults have IgE to common food allergens), and most people don't have any symptoms when they eat the food. As allergists, our thinking has been that it is not important if people have IgE to foods, as long as they don't have symptoms when they eat the food,” she said.

Funded by the National Institute of Allergy and Infectious Disease and an AAAAI Faculty Development Award to her collaborator Jeff Wilson at the University of Virginia, this research used two methods to examine the association between IgE sensitization to foods and cardiovascular mortality. Data from 4,414 adults who participated in The National Health and Examination Survey (NHANES) and 960 participants in the Wake Forest site of the Multi-Ethnic Study of Atherosclerosis (MESA) cohort were used. Participants were enrolled in MESA from 2000-2002 and followed for up to 19 years. Participants were enrolled in NHANES from 2005 to 2006 and data on mortality up to 14 years were tracked. Total and specific IgE was measured to cow’s milk, egg, peanut, shrimp, and a panel of aeroallergens for the NHANES group. IgE to cow’s milk, alpha-gal, peanut, dust mite and timothy grass were measured in the MESA group. In NHANES, 229 cardiovascular deaths were recorded and 960 deaths from MESA were also reported. Milk sensitization was particularly associated in both NHANES & MESA. Researchers also discovered that food sensitization to shrimp and peanut were both additional risk factors for heart disease.

It is also important to note that associations in the findings related to food sensitization rather than clinical allergy. Although researchers did not have access to information about clinical food allergy in either cohort, they expect that individuals who report regularly eating a food allergen on food frequency questionnaires were not showing symptoms of a food allergy. Thus, the findings that showed how associations were strengthened when researchers excluded those who avoided the food suggest that these findings were most relevant to those who have not been diagnosed with food allergy. Keet says the results raise questions about whether these apparently non-allergic individuals may have long-term consequences from consuming foods to which they are sensitized.

The study states that aside from two recent reports linking IgE to the unusual carbohydrate allergen alpha-gal to coronary artery disease, cardiovascular disease had not previously been identified as a long-term complication of food sensitization. However, there is now substantial evidence for the importance of allergic-type immune pathways in normal cardiac physiology and heart disease. Because discovering the link between milk sensitization with cardiovascular mortality is new, Keet says there’s more to explore as far as the relevance of food sensitization and diet in cardiovascular disease development.

“More research needs to be done about how sensitization to common food allergens is related to cardiovascular disease,” she said. “While this study provides good evidence of an association between sensitization to these allergens and death from cardiovascular disease, there is much work to be done to understand if this is a causal relationship.”

Media contact: Brittany T. Phillips, Communications Specialist, UNC Health | UNC School of Medicine