news – Centre for Heart Lung Innovation

New research from the Centre for Heart Lung Innovation (HLI) has identified inflammation in the lungs’ smallest airways as the cause of pulmonary long COVID-19.

A research team led by the HLI’s Director, Dr. Don Sin, used xenon MRI, an advanced imaging technology, and single-cell sequencing of lung samples, supported by the HLI’s biobank team, to uncover the underlying mechanism behind persistent respiratory symptoms in long COVID patients. These findings were published in three articles in the European Respiratory Journal.

Dr. Rachel Eddy prepares the MRI at St. Paul’s Hospital. (Photo courtesy of Providence Research)

What is long COVID?

Five years on from the beginning of the COVID-19 pandemic, many COVID patients continue to be impacted by residual symptoms lingering after the initial illness, a condition known as long COVID. Affecting approximately 10 per cent of people infected with COVID-19, long COVID is a multi-system disorder with diverse presentations, including brain fog, fatigue, joint pain, shortness of breath, wheeziness, and cough. These symptoms can significantly impact patients’ quality of life and are associated with increased health care costs.

The HLI research team focused on identifying the cause of pulmonary long COVID, which presents with persistent lung symptoms and accounts for approximately one-third of long COVID cases.

Detailed lung scans made possible with xenon MRI

Despite experiencing often-debilitating symptoms, 80 to 90 per cent of the long COVID participants tested by the HLI team showed normal results on standard lung function tests and CT scans.

“I distinctly remember a nurse who could no longer work after recovering from acute COVID. He had so much shortness of breath, even with just minimal exertion, that he had to go on long-term disability. And yet, his breathing test was normal. His CT scan was also normal,” says Dr. Sin.

The researchers suspected that these standard tests were not sensitive enough to detect the root cause of these symptoms, and so they turned to hyperpolarized xenon gas magnetic resonance imaging (xenon MRI), an advanced method that enables three-dimensional imaging of lung function.

In 2019, with support from St. Paul’s Foundation and the Canada Foundation for Innovation, St. Paul’s Hospital obtained a specialized MRI and hyperpolarizer. Together, these devices enabled the use of inhaled hyperpolarized xenon gas to image the lungs’ airways and track the flow of oxygen into the bloodstream, a process known as gas exchange. Hyperpolarization enhances the xenon’s magnetism, making it more visible to the MRI.

Images from a study using xenon gas MRI show lung function differences in participants who never had COVID-19, those who recovered, and those with long COVID. (European Respiratory Journal)

“It’s particularly the gas exchange component that makes xenon MRI so unique,” says Dr. Rachel Eddy, Director of the HLI’s MRI core who launched the centre’s xenon MRI research program. As xenon follows the same gas-transfer pathways as oxygen, xenon MRI is able to image the separate components of gas exchange, allowing researchers to identify where in the lungs a problem is occurring.

By analyzing combined data from the HLI, Duke University, and the University of Kansas Medical Centre from xenon MRI scans of a large cohort of long COVID patients, the researchers identified four clusters, or subgroups, of pulmonary long COVID, which were characterized by different types of gas exchange abnormalities.

The researchers determined that pulmonary long COVID is primarily driven by gas exchange problems in the small airways, where oxygen enters the bloodstream, which cannot be visualized in traditional scans or lung function tests.

“That’s what hyperpolarized xenon gas MRI does. It lets us see beneath the surface,” says Dr. Sin.

Single-cell profiling identified inflammation in small airways

To determine the cellular and molecular drivers of these abnormalities, a subset of patients who had participated in the xenon MRI study underwent bronchoscopies to take tissue samples from their small airways, which were analyzed with single-cell RNA sequencing.

Because single-cell sequencing requires fresh, living tissue, the research team faced logistical challenges in transporting the samples from St. Paul’s Hospital to the University of British Columbia, where the sequencing equipment is located. To ensure the cells survived the journey, they utilized the expertise of the HLI biobanking team to process and prepare the samples.

“The biobanking facility is much more than just keeping things in the freezer. It’s actually developing protocols and methods to enable the use of human volunteer tissues for research,” says Dr. Sin. The HLI is home to several influential biobanks, including the James Hogg Lung Biobank and the Bruce McManus Cardiovascular Biobank.

The single-cell sequencing found that the pulmonary long COVID patients had neutrophilic inflammation in the small airways. Neutrophils, immune cells that normally help fight infection, were continuing to trigger an immune response, even though the virus was gone.

“They’re like dirty bombs. They come in to kill the bacteria or viruses,” says Dr. Sin. “Once all the pathogens are killed off, then the body should shut down the recruitment of these cells into the small airways.” In pulmonary long COVID patients, these cells remain, causing damage to the small airways and driving the symptoms of pulmonary long COVID.

Inflammation is likely to resolve

A few key questions remain, such as why some people develop long COVID while others recover fully. It is still unknown why these inflammatory cells persist, or if this phenomenon could occur with other viruses like influenza or RSV.

“We don’t think this is specific to coronavirus. If a virus gets in deep enough into your airways, we think that this can trigger, in some individuals, a persistent response for a period of time,” says Dr. Sin.

Encouragingly for pulmonary long COVID patients, Dr. Sin and his team believe that this inflammation, which is relatively mild, will likely resolve on its own over time, provided it isn’t exacerbated by factors like smoking, exposure to wildfire smoke, or additional COVID-19 infections.

“Prevention, breathing in clean air, refraining from smoking and dusty environments, those are, I think, very important preventative measures. If patients keep on doing that, over time we think this inflammation will settle on its own,”
— Dr. Don Sin, HLI Director

This article was originally written by Grace Jenkins and published on March 24, 2025 through Providence Research. Read the article on Providence Research here.

On this year’s National Indigenous Languages Day (March 31, 2025), we highlight Dr. Pat Camp’s important work in incorporating Indigenous language into culturally safe healthcare and research practices.

Dr. Pat Camp, a Principal Investigator at the Centre for Heart Lung Innovation (HLI), reflects on her research helping people manage chronic lung conditions through exercise, education, and support – a process called pulmonary rehabilitation.

Through collaboration with Carrier Sekani Family Services, Dr. Camp shares how her team is learning to respectfully incorporate Indigenous knowledge into pulmonary rehabilitation research. This includes using the Carrier (Dakelh) language to name body parts—an approach to make pulmonary rehab more culturally safe, respectful, and healing.

“There’s a lot more that we can do”
— Dr. Pat Camp, HLI Principal Investigator

Watch Dr. Pat Camp’s Story

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Learn about National Indigenous Language Day:

New research on low-carb, high-fat diets earns a spot among the five most-read articles in one of cardiology’s leading journals.

A study led by Dr. Iulia Iatan and Dr. Liam Brunham at the Centre for Heart Lung Innovation (HLI) has been recognized as one of JACC: Advances’ Top 5 Most-Read Articles of 2024. Published in one of the most prominent cardiovascular journals, the study’s ranking underscores its impact and the global interest in its findings.

“It is an honour to see our study recognized among the most-read articles in JACC: Advances for 2024. This reflects the growing interest in understanding how dietary choices impact long-term heart health,” said lead author Dr. Iulia Iatan, a clinician-scientist and former postdoctoral fellow at UBC’s Centre for Heart Lung Innovation and the Healthy Heart Program Prevention Clinic at St. Paul’s Hospital.

“To our knowledge, this was one of the first studies to show an association between low-carbohydrate high-fat diets, increased cholesterol, and higher risk of cardiovascular events.”
— Dr. Iulia Iatan, HLI’s former postdoctoral fellow

“I hope these findings encourage both the public and healthcare professionals to consider the long-term effects of these diets, and also inform clinical practice and public awareness on the importance of heart-healthy nutrition.”

Trendy “keto-like” diet under scrutiny

Low-carbohydrate, high-fat (LCHF) diets have gained popularity for various health reasons, including weight loss and diabetes management, but their long-term effects on heart health have been uncertain. This study found that “keto-like” diets are linked to higher cholesterol levels and a twofold increase in major heart problems, including heart attacks and strokes over the next decade. The risk was highest for those with a genetic predisposition to high cholesterol.

To investigate this link, Dr. Iatan and the team analyzed data from the UK Biobank, tracking 305 participants who followed an LCHF diet—defined as <25% of daily calories from carbohydrates and >45% from fat—over an average of 12 years. They examined lipid levels and cardiovascular events, comparing outcomes to those on normal, standard diets.

A further finding from the study was that the risk of severely elevated cholesterol was highest among those individuals with an elevated polygenic risk score, suggesting a genetic predisposition to diet-induced increases in cholesterol in some people.

These findings emphasize the need for caution among followers of this dietary pattern, especially for those with high cholesterol or a personal or family history of heart disease.

What’s next?

Dr. Brunham and colleagues plan to continue examining how genetic differences influence response to various dietary patterns and their effects on heart health. Future research will also explore whether genetic testing can help create more personalized dietary recommendations and improve understanding of variations between individuals in response to different diets.

A big moment for HLI

This recognition reinforces HLI’s leadership in cardiovascular research and its role in providing strong, evidence-based guidance on health and disease prevention. With this study ranking among JACC: Advances’ most-read of the year, HLI continues to drive research that informs medical practice and public health.

“This is a great recognition of the quality of cardiovascular research taking place at HLI and our centre’s leadership in the field of lipid disorders.”
— Dr. Liam Brunham, HLI’s principal investigator

“Seeing Change Inspires Change”—YWCA

The YWCA Women of Distinction Awards celebrate women whose contributions drive innovation and mentorship. Dr. Luo’s nomination highlights her leadership in scientific research and her impact as a mentor, inspiring the next generation of women in STEM.

“As a woman in science, I have experienced the challenges of gender disparity in research. I advocate for Gender Equity because promoting equal opportunities in science empowers more women to lead and shape the future of technology.”
—Dr. Honglin Luo, HLI principal investigator

Show Your Support—Vote for Dr. Luo!

The YWCA Women of Distinction Awards also include a Connecting the Community category, where the public can vote for their favourite nominee. Cast your vote for Dr. Luo today before April 1, 12:00 PM!

🔗 Vote now: ywcavan.org/CCA-vote

Two HLI lung health researchers are being recognized with a prestigious national award.

Congratulations to HLI principal investigators, Dr. Pat Camp and Dr. Christopher Carlsten, who have been honoured with the King Charles III Coronation Medal—a national recognition of their contributions to Canada and the community.

This award, the first commemorative medal marking the coronation of His Majesty King Charles III on May 6, 2023, celebrates individuals who have made a significant impact in Canada. Recipients are recognized for their work in areas that reflect values shared by both King Charles III and Canadians, including service, environment and sustainability, and diversity.

Dr. Camp is breaking down barriers to lung health care. As a physical therapist and researcher, her work focuses on making pulmonary rehabilitation and physical activity programs more accessible, particularly for people in rural and First Nations communities. By working directly with these communities, she helps co-design programs that reflect their needs and ensure their voices are heard.

Dr. Carlsten is exposing the dangers in the air we breathe. His research focuses on how air pollutants, like diesel exhaust, harm lung health over time, working to better understand the risks of breathing in polluted air at work or in the environment. As a clinician-scientist, he treats patients affected by workplace and environmental toxins, translating research into real-world care.

Drs. Camp and Carlsten are among 39 distinguished Canadians nominated by the Canadian Lung Association (CLA) for their outstanding contributions to respiratory health research. In British Columbia, they are two of just three recipients of this national honour.

Congratulations again to Dr. Camp and Dr. Carlsten on this well-deserved recognition!

Connect

Dr. Pat Camp on X (Twitter): @UBCPulmRehabRes
Dr. Christopher Carlsten’s Lab

Providence Research’s recent report explores how biobanks fuel scientific and medical discoveries, highlighting HLI’s unique heart and lung biobanks as vital resources for research.

A single biospecimen, such as a heart tissue collected during surgery, has the ability to contribute to numerous research projects, leading to significant scientific and medical breakthroughs. Biobanking is the process of collecting biological samples along with clinical and demographic data, enabling researchers to study diseased tissues and disease development in greater detail.

A new Providence Research report, A Look Inside Providence Research Biobanks, explores the purpose of biobanks and their impacts on medical research and education. Among the biobanks featured in the report are the Bruce McManus Cardiovascular Biobank (BMCB) and the James Hogg Lung Biobank (JHLB)–western Canada’s largest heart and lung tissue biobanks–housed at the Centre for Heart Lung Innovation (HLI). Drs. Gordon Francis, Stephanie Sellers, Zachary Laksman, and Tillie Hackett are featured as researchers who have benefited from HLI’s biobank resources.

James Hogg Lung Biobank (JHLB)

Established in 1977, and now directed by HLI’s Dr. Tillie Hackett, the JHLB is the longest-running lung biobank in Canada and contains more than 90,000 specimens from over 3000 patients. It has been a significant resource for lung research, contributing to over 800 published research projects since its founding.

A global leader in lung biobanking, the JHLB has set internationally adopted protocols for tissue preservation. Its methods allow specimens to be studied structurally and at the molecular level, driving advancements in lung disease research, including COPD, pulmonary fibrosis, and asthma.

Bruce McManus Cardiovascular Biobank (BMCB)

Led by HLI’s Dr. Ying Wang, the BMCB holds more than 100,000 human cardiovascular biospecimens with detailed clinical data, including 544 explanted hearts from transplant patients, 14,000 heart valves, and 600 aorta specimens. Housed at St. Paul’s Hospital, the only hospital in British Columbia performing adult heart transplants, the BMCB has been a cornerstone of cardiovascular research and education since 1982.

“For almost the entire time that heart transplants have been performed at St. Paul’s, patients have been donating their removed hearts to our tissue bank. This is an incredibly precious and unique resource in the world.”
Dr. Gordon Francis, HLI principal investigator

Explore the Full Report

To learn more about the impact of biobanks in medical research, explore A Look Inside Providence Research Biobanks, and explore the Bruce McManus Cardiovascular Biobank and James Hogg Lung Biobank.

HLI researchers receive over $1.86 million from CIHR’s Fall 2024 Project Grant competition.

The Centre for Heart Lung Innovation (HLI) is proud to celebrate the achievements of 3 principal investigators who have been awarded funding through the Canadian Institutes of Health Research (CIHR) Project Grants, Fall 2024 competition. This funding will drive innovative research in cardiovascular health, infection and immunity, and transplant medicine, advancing scientific discovery and improving patient outcomes.

From left to right: Dr. Scott Tebbutt, Dr. James Russell, Dr. Pascal Bernatchez

Congratulations to the following recipients:

Dr. Scott Tebbutt – $229,500

Metabolomic biomarkers for early detection of acute cellular rejection in heart transplant recipients (HLI Co-investigator: Dr. Chengliang Yang) – CIHR Link

For people with severe heart failure, heart transplantation is a life-saving surgery. However, the body’s immune system may attack the new heart in a condition called acute cellular rejection (ACR). Currently, detecting ACR requires invasive biopsies.

Dr. Scott Tebbutt and HLI Co-investigator Dr. Chengliang Yang are looking into non-invasive blood tests to identify ACR after patients undergo a heart transplant surgery. The development of this test could help doctors quickly identify and treat rejection, improving the health of heart transplant recipients.

Dr. James A. Russell – $719,101

Development of Lipid nanoparticle RNA systems as novel therapeutics for endotoxemia resulting from severe bacterial infections – CIHR Link

Severe bacterial infections, which can lead to pneumonia and sepsis, are leading causes of death worldwide. While antibiotics are essential, some bacteria develop resistance (“superbugs”), making infections harder to treat.

Dr. James A. Russell’s team is developing RNA-based drugs that work by blocking harmful genes or boosting the body’s defenses during infections. These next-generation drugs delivered using lipid nanoparticles, a safe delivery vehicle, could enhance the body’s ability to fight infections, working alongside antibiotics to improve treatment outcomes.

As a commercialization grant, inventions can be patented (IP) and then transferred (“licensed”) to a company called Resolve Nanotherapeutics, that will drive clinical development of these urgently-needed drugs for severe infections.

Dr. Pascal Bernatchez – $914,175

Activation of the chronic endothelial function reserve for the prevention and regression of aortopathies (HLI Co-investigator: Dr. Scott Tebbutt) – CIHR Link

Aortopathies are a group of diseases that affect the aorta, the largest blood vessel in the body. These conditions can weaken the aorta’s walls, increasing the risk of life-threatening conditions like tears and aneurysms (ballooning of the vessel). While patients are often given medication to lower blood pressure to reduce the damage, these treatments do not always stop the disease from progressing.

Dr. Pascal Bernatchez and HLI co-investigator Dr. Scott Tebbutt are researching how to activate natural defenses of blood vessels to improve vessel health in aortopathies. Their previous studies suggest that increasing nitric oxide levels—a chemical released naturally in response to blood flow—may better protect blood vessels. They aim to study this further and are also working to develop blood biomarkers that can indicate whether a patient’s treatment is effective. This approach would offer a more precise way to monitor and personalize care.

We congratulate all the awardees on this well-deserved recognition and look forward to seeing their contributions to advancing health research.

Dr. Yao (middle) with Drs. Evelyn Yim (left) and Molly Shoichet (right)

Join us in welcoming Dr. Yuan Yao, Assistant Professor in the Department of Mechanical Engineering and Division of Cardiology, Department of Medicine at UBC. Dr. Yao is the latest addition to our growing list of Principal Investigators (PIs), and her interdisciplinary interest in bioengineering approaches to regenerate vascular and cardiac tissues adds another dimension to our research efforts towards the prevention and treatment of heart disease.

What is your field of expertise?

My field of expertise is where engineering and medicine overlap. I’m primarily focused on biomaterials for soft tissue engineering, looking into diseases like coronary artery disease and myocardial infarction. My goal is to see how we can create biomaterial scaffolds, manipulating cell responses to build an engineered tissue model that we can test drugs and promote tissue regeneration with.

How did you develop your interest in bioengineering?

That’s actually a very interesting question because it’s a question I’ve been asking myself all the time. It’s kind of funny because my parents are both in biology, and when I was relatively young, I told them I would never step into biology, but now I’m here. My past training was more in the engineering, material science realm, but when I was looking into real world applications for all the materials we developed, I watched this drama called Westworld. In the beginning of that drama, there’s a robot arm printing muscle filaments. I thought it was really cool, and it gave me the idea to use our material to do something like that and make it into reality instead of just something we see in fictional movies or dramas.

What are you most looking forward to in your work at the HLI?

After joining the HLI, I realized that all of us do research in very cross-disciplinary fields. Our PIs are evenly split between being research-based and clinical-based, so the centre offers a really great opportunity not just to collaborate with others in terms of basic science, but also to translate our research into actual bedside knowledge. That clinical translation is something I look forward to working on here at the HLI.

What is one of the proudest moments of your career so far?

Well, I would say that I’m not someone who’s easily satisfied, so I would probably say that moment hasn’t come yet. I mean, it’s been a long journey since I graduated from undergrad and I’ve completed quite a number of milestones, but I just started my first independent academic position as an Assistant Professor, so there’s a lot for me to look forward to still. Maybe if you asked me 20 years later, I would have a better answer.

You answered this question very similarly to Dr. Yasir Mohamud, who is also a young researcher at the HLI. Is a forward-looking mentality crucial for anyone trying to make it in the scientific field, since it’s so competitive and difficult?

I think it’s a pretty common mentality for people in research, since we are always looking into something that is not achieved yet, so we can’t stop and settle with what we have. We need to explore further, dive deeper, and that acts as motivation for people to push their careers forward.

Unfortunately, it is common for teachers, professors, doctors, “professionals”, to be looked down upon when they are young due to a perceived lack of expertise. Have you faced any barriers in this regard? How did you overcome it?

Actually, one of the most frequent comments I’ve gotten, maybe 20-30 times in the last three months, is people see me and they say “Oh, you look like a student”. I mean, I appreciate that, I’m happy I look young, but at the same time, it means they don’t see you as an independent professor or researcher, which can be a little frustrating. But when I talk to my senior colleagues, they tell me that this is really a moment to cherish, because this is when you don’t have that big of a generation gap between you and the students. So you can be relatively closer with them and communicate better, which is a good thing.

You’ve studied and worked at universities in China, Ontario, and now British Columbia. How do you compare these different institutions?

In Canada, courses are generally more interactive and students have more opportunities to communicate with course instructors. Comparing my experience in Ontario to Vancouver, I’ve noticed that UBC has a stronger emphasis on undergraduate education. Beyond the institutions, though, the cities feel pretty different. I was told Vancouver has really good weather with milder winters, but I’ve noticed that the trade off is the all the rain we get. People in Toronto also speak a lot faster, whereas people in Vancouver are more chill and laid-back.

What do you like to do outside of work?

Right now, I feel like I don’t have much free time, but I used to like watching stand-up comedies. When you’re doing any kind of work, there will be some frustrations from time to time, so it’s important to take things easy and learn how to be light-hearted.