Recognizing Stem Cell Research

Dr. Stephanie Xie receives the Till & McCulloch Award for her work studying blood stem cells.

Dr. Stephanie Xie, Scientist at UHN’s Princess Margaret Cancer Centre (PM) and Assistant Professor in the Department of Medical Biophysics at the University of Toronto’s Temerty Faculty of Medicine, has been named the recipient of the 2026 Till & McCulloch Award for her research on the impact of repeated infections and stress on blood-forming stem cells.

The award recognizes the most impactful peer-reviewed article of the year by a stem cell or regenerative medicine researcher working in Canada. Dr. Xie received the award for her Nature publication titled, “Human haematopoietic stem cells remember inflammatory stress.”

In this study, Dr. Xie, also an Allan Slaight Scientist at PM, led a team examining how stress from long-term inflammation can drive the aging of blood cells and increase the risk of cancer.

Blood stem cells (hematopoietic stem cells, HSCs) in the bone marrow are responsible for continuously replenishing blood cells throughout life. However, repeated inflammation from infections and other stresses can gradually impair their function with age.

To understand how blood stem cells adapt and respond to inflammation, the researchers generated lab models of inflammation to analyze human HSCs. They identified a previously unrecognized subset of HSCs, called inflammatory memory stem cells (HSC-iM) that were distinct in their gene activity and retained a memory of previous inflammation. These cells retained molecular changes after inflammation had resolved, were associated with age-related blood cell changes, and passed inflammatory signatures to downstream immune cells.

These findings help explain why inflammatory experiences earlier in life may shape a person’s health decades later and provide new tools to investigate why aging and age-related diseases can differ between individuals.

Dr. Xie will accept the award at the 2026 Till & McCulloch Meetings in Vancouver.

To learn more about this study, see the Research at UHN news story.

For more details on this prestigious award and the Till & McCulloch Meetings, visit the website here.

UHN Researchers Join Hall of Fame

Drs. Frances Shepherd and Anthony Lang are 2027 inductees into Canadian Medical Hall of Fame.

Dr. Frances Shepherd, Emerita Scientist at UHN’s Princess Margaret Cancer Centre (PM) and Dr. Anthony Lang, Senior Scientist at UHN’s Krembil Brain Institute (KBI) are 2027 inductees of the Canadian Medical Hall of Fame for their transformative work in lung cancer and movement disorders, respectively.

The Canadian Medical Hall of Fame inducts Canadians whose leadership, integrity, and contributions to health sciences, in Canada and around the world, have led to extraordinary improvements in human health.

Dr. Frances Shepherd | Emerita Scientist, UHN’s Princess Margaret Cancer Centre

Dr. Shepherd, an international leader in clinical lung cancer research, is also a Professor Emerita at the University of Toronto. Before her retirement in 2026, she held the Scott Taylor Chair in Lung Cancer Research at Princess Margaret Cancer Centre and the rank of University Professor at the University of Toronto. With a career spanning over 40 years, she has led and collaborated on more than 100 clinical trials and authored over 650 peer-reviewed publications. Her work has reshaped standards of care and treatment for lung cancer worldwide.

Her research has focused on developing and evaluating combined treatment approaches, as well as new therapies for patients with both small cell and non-small cell lung cancer. She led a landmark international trial that demonstrated the benefits of the chemotherapy drug docetaxel for patients with advanced disease, improving both survival and quality of life and ultimately influencing treatment guidelines and drug approvals worldwide.

She also led a pivotal study showing that chemotherapy after lung cancer surgery could significantly reduce the risk of death and improve five-year survival, establishing a treatment regimen that remains the standard of care today. In parallel, she helped establish lung cancer tumour banks linked to clinical studies, creating an invaluable resource for advancing molecular research into the disease.

Dr. Shepherd also played a key role in the introduction of molecularly targeted treatments for lung cancer, demonstrating the benefits of the epidermal growth factor receptor (EGFR) inhibitor erlotinib and helping to identify genetic markers associated with treatment response.

Dr. Shepherd has received many distinctions in recognition of her research achievements, including being named an Officer of the Order of Ontario (2007), receiving the Order of Canada (2016), the Gairdner Foundation Wightman Award (2018), and the Lifetime Contribution Prize from the Canadian Cancer Society (2022), among many others.

Dr. Anthony Lang | Senior Scientist, UHN’s Krembil Brain Institute

Dr. Anthony Lang is an internationally renowned neurologist and movement disorders specialist. He is a Professor in the Department of Medicine at the University of Toronto and also holds several distinguished appointments, including the Lily Safra Chair in Movement Disorders, the Director of the Edmond J. Safra Program in Parkinson's Disease, and the Director of the Rossy PSP Centre at UHN, and the Jack Clark Chair for Parkinson’s Disease Research at U of T.

Over a career spanning more than four decades, he has helped shape the global understanding and treatment of Parkinson disease and other movement disorders. He has authored more than 1100 peer-reviewed publications and is among the world's most highly cited researchers in the field, receiving the Highly Cited Researcher distinction from Clarivate.  

Dr. Lang’s research has focused on understanding how Parkinson disease and related movement disorders develop and progress, improving diagnosis and developing new treatments to slow the disease and manage its symptoms. He founded and serves as the Director of the Movement Disorders Clinic at UHN’s Toronto Western Hospital, which has grown into one of the leading centres of its kind internationally.

His work has contributed to the development of international guidelines for diagnosing Parkinson disease and identifying its earliest stages, helping pave the way for earlier detection and future treatments aimed at slowing disease progression. He has also advanced the understanding of related neurological disorders, including progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), by helping establish diagnostic criteria that improve early and accurate diagnosis and support the development of new therapies.

In recognition of his contributions to neuroscience and Parkinson disease research, Dr. Lang was appointed an Officer of the Order of Canada in 2010. He has also received numerous national and international honours, including being elected as a Fellow to the Royal Society of Canada (2011) and the Canadian Academy of Health Sciences (2011), the Weston Brain Institute International Outstanding Achievement Award (2018), and the University of Toronto Dean's Lifetime Achievement Award (2020).

As highly respected leaders in their fields, Dr. Lang and Dr. Shepherd’s contributions have had significant and lasting impacts on health.

Congratulations to Drs. Shepherd and Lang and all of the inductees!

See the full announcement here. 

Designing with Intention

Exploring how road intersection design shapes safety and mobility for people with disabilities.

Image Caption: For people with disabilities, well-designed and well-maintained intersections can help make navigating busy urban environments safer and more accessible.

Expanding the Reach of CAR T

New approach to specialized cancer immunotherapy may improve precision and broaden impact.

Image Caption: Cancer immunotherapies, like CAR T, train immune cells to recognize cancer-specific targets. One way they do this is by targeting small pieces of cancer proteins that are displayed on the cell surface by molecules called HLA. Researchers are trying to improve the specificity and effectiveness of this approach.

Chimeric antigen receptor T cell therapy (CAR T) has transformed the treatment of certain blood cancers. However, this approach has been difficult to apply to other cancers, such as solid tumours. Researchers at UHN’s Princess Margaret Cancer Centre (PM) have identified a new CAR T strategy that can target a protein found in many cancer cells, potentially broadening its application to more cancer types.

CAR T is a cancer immunotherapy that works by harnessing and reprogramming a patient’s own immune cells to recognize and attack cancer cells. A major challenge of these therapies is identifying suitable targets that are also unique to cancer cells.

CAR T therapies are designed to recognize and target specific proteins on the surface of cancer cells (surface antigens). This can be a limitation of the therapy as it is challenging to identify surface targets that are specific to cancer cells. In addition, these therapies often target protein fragments presented by human leukocyte antigen (HLA) Class I molecules on cell surfaces. However, HLA Class I molecules are found on most cells, making it difficult to distinguish cancer cells from healthy cells, increasing the risk that these therapies will also affect healthy tissue.

Researchers have begun exploring protein fragments presented by HLA Class II molecules—which are found on fewer healthy cells but can be present at higher levels on some cancer cells.

Wilms tumour 1 (WT1) is a protein found inside cells that has been associated with many cancers, including leukemia. Because conventional CAR T cells typically recognize proteins on cell surfaces, WT1 has been difficult to target using this approach. PM researchers have developed a new approach, designing CAR T cells that recognize WT1 protein fragments presented by HLA Class II molecules.

In laboratory studies, the engineered CAR T cells successfully identified and attacked leukemia cells that presented WT1 fragments through HLA Class II molecules. The therapy showed strong anti-cancer activity both in cell-based experiments and preclinical models, while selectively targeting cancer cells. The WT1-CAR T cells only recognized and attacked cancer cells when both WT1 and HLA Class II molecules were present together.

Most immune therapies that target proteins presented by HLA molecules are restricted to a specific HLA type, limiting the patients who may be eligible for treatment. However, this new WT1-CAR T was able to recognize the WT1 protein fragment when it was presented by 18 of the 20 HLA Class II molecules tested. This could make the approach applicable to a broader and more genetically diverse group of patients.

While further research and clinical testing are needed, this approach could expand CAR T cell therapy beyond its current applications, offering new treatment possibilities for people with myeloid leukemia and other cancers, such as ovarian cancers and mesothelioma, that have remained difficult to treat.

Evey Zheng, a Doctoral Candidate at UHN’s Princess Margaret Cancer Centre, is the co-first author of the study.

Dr. Chung-Hsi Wang, a Postdoctoral Research at UHN’s Princess Margaret Cancer Centre at the time of the study, is the co-first author of the study.

Dr. Naoto Hirano is a Senior Scientist at UHN’s Princess Margaret Cancer Centre and a Professor in Immunology at the University of Toronto. He is the corresponding author of the study.

This work was supported by the Canadian Institutes of Health Research, the Longo Family Cancer Foundation, the Ira Schneider Memorial Cancer Research Foundation, and The Princess Margaret Cancer Foundation.

Dr. Naoto Hirano is Tier 1 Canada Research Chair in Immunology to Immunotherapy.

Dr. Hirano reports a patent for Anti-WT1 Antigen-Binding Proteins and Uses Thereof pending.

Zheng EYF, Wang CH, Ochi T, Ohashi Y, Ihara F, Fukao S, Ito Y, Boukhaled GM, Wang BX, Han DH, Wei X, Yolmo P, Burt BD, Saso K, Matsunaga Y, Ly D, Kagoya Y, Butler MO, Minden MD, Hirano N. CAR T Cells Targeting an Intracellular Leukemia Antigen Promiscuously Presented by Diverse HLA-II Alleles. Blood Cancer Discov. 2026 Sep 3;7(5):813-828. doi: 10.1158/2643-3230.BCD-25-0230.
(link is externalBlood Cancer Discov. 2026 Sep 3;7(5):813-828. doi: 10.1158/2643-3230.BCD-25-0230. Blood Cancer Discov. 2026 Sep 3;7(5):813-828. doi: 10.1158/2643-3230.BCD-25-0230. Blood Cancer Discov. 2026 Sep 3;7(5):813-828. doi: 10.1158/2643-3230.BCD-25-0230.

Exploring Safer Hospital Discharges

New study shows how community warming centres have the potential to reduce hospital burden.

Image Caption: Overcrowding in emergency departments can lead to issues such as increases in mortality and staff distress. Inadequate sheltering options contribute to overcrowding as hospital discharge for those experiencing unsheltered homelessness is unsafe during the winter.

People experiencing homelessness often visit emergency departments (EDs) as a source of shelter, particularly during the colder months. Researchers at UHN found that hospital-affiliated warming centres, operated in collaboration with community partners, have the potential to reduce ED length of stay for people experiencing homelessness.

In Toronto, rates of non-urgent ED visits by people experiencing homelessness during winter months have been increasing. This is often due to limited sheltering options, as people experiencing homelessness may seek care in the ED for a range of concerns, including access to shelter.

Following an ED visit, people experiencing unsheltered homelessness may face barriers to accessing shelter beds and other safe discharge locations. Due to the medical risks associated with discharge to an unsafe environment, this can result in patients remaining in the ED even after their medical needs have been addressed. This delay contributes to ED overcrowding, which causes reduced service quality, increased risk of mortality, and greater staff distress.

As the number of people experiencing homelessness continues to rise, identifying safe discharge options is becoming increasingly important to help reduce ED overcrowding while ensuring patients receive appropriate support after leaving the hospital. To address this need, UHN’s Social Medicine program worked with community partners to establish a hospital-affiliated warming centre in Toronto in 2023 to provide a safe location for discharges during the winter months.

To examine the impact of this warming centre, the researchers looked at the relationship between ED visits by people experiencing homelessness and the operation of the Toronto-based hospital-affiliated warming centre. This warming centre were operated in collaboration with a community partner with expertise in supporting people experiencing homelessness. The team analyzed administrative data on ED and hospital-affiliated warming centre utilization from the winter seasons between November 2022 and April 2025.

The research team found that the hospital-affiliated warming centre supported 1,196 visits during its first year and 638 visits during the second year. In the second year, when a referral pathway from the ED to the warming centre was open, it was associated with decreased ED lengths of stay. This suggests that the referral pathway may have helped facilitate faster discharges.

The study also found that in the second year, municipal shelter system volumes correlated with ED length of stay, suggesting that shelter capacity may influence patient flow in the ED.

Overall, the researchers say that hospital-affiliated warming centres have the potential to reduce ED burden. More research and monitoring of these interventions are needed to ensure optimal outcomes.  The researchers note that improved access to emergency shelter beds and affordable and supportive housing is necessary to improve the health of people experiencing homelessness.

Dr. Nick Kerman, Research Associate with the Gattuso Centre for Social Medicine at UHN, and Clinical Psychologist at UHN, is the first author of the study.

Dr. Kate Hayman, Clinician Investigator and emergency physician at UHN, is the corresponding author of the study. She is an Assistant Professor in the Department of Medicine at the University of Toronto.

This work was supported by UHN’s STAR-EM (Summer Training and Research in Emergency Medicine) program and UHN Foundation. The warming centre was developed and delivered through collaboration among UHN Emergency Medicine, the Gattuso Centre for Social Medicine at UHN, and a community partner with expertise supporting people experiencing homelessness.

Kerman N, Yanikomeroglu S, Ragusila A, Vitkin N, Coyle S, Steer L, Boozary A, Hayman K. Development of a hospital-affiliated warming centre to reduce emergency department pressures among patients experiencing homelessness. CJEM. 2026 Aug 10. doi: 10.1007/s43678-026-01250-y. Epub ahead of print. 

Excellence in Physician-Led Research

Drs. Bhat and Howe receive SUMO–UHN Distinguished Physician Investigator Awards.

Image Caption: Dr. Mamatha Bhat is a transplant clinician–scientist at UHN’s Ajmera Transplant Centre, and Dr. Kathryn Howe is a vascular surgeon–scientist at UHN’s Peter Munk Cardiac Centre.

Two outstanding clinician–scientists—Dr. Mamatha Bhat and Dr. Kathryn Howe—have been named the inaugural recipients of the SUMO–UHN Distinguished Physician Investigator Award, a strategic salary support award designed to retain exceptional mid-career physician-researchers while accelerating health innovation at UHN.

Dr. Bhat, a transplant hepatologist and clinician-scientist at UHN’s Ajmera Transplant Centre, leads an internationally recognized research program focused on developing and translating artificial intelligence (AI) into clinical practice in transplantation. Her research aims to make access to liver transplantation more equitable and to improve outcomes across the transplant journey, from supporting complex decisions about transplant candidacy and organ allocation to predicting post-transplant complications and detecting early graft injury before irreversible damage occurs. With support from the SUMO–UHN Award, Dr. Bhat will accelerate the prospective evaluation and clinical deployment of AI-powered decision-support systems, integrating these tools into real-world transplant workflows and evaluating their safety, effectiveness, and impact on patient care. This work will provide a framework for the responsible implementation and scaling of AI across transplant programs in Canada and internationally, while strengthening UHN’s position as a global leader in translating AI innovation into clinical care.

Dr. Howe is pursuing a bold new approach to treat atherosclerosis, a buildup of plaque in blood vessels that underlies cardiovascular diseases such as heart attacks and stroke. As a vascular surgeon–scientist at UHN’s Peter Munk Cardiac Centre, Dr. Howe leads an innovative research program aimed at improving our understanding of how the cells that line blood vessels communicate with surrounding tissues. Her team is developing a novel precision medicine platform to deliver targeted treatments directly into diseased blood vessel walls. Funding from the award will support this work, ultimately aiming to prevent the development of cardiovascular disease, which remains one of the leading causes of disease burden worldwide.

This award was established as a unique partnership between the Sinai–UHN Academic Medical Organization (SUMO) and UHN's Canada Leads initiative to strengthen UHN's leadership in translational research, clinical innovation, commercialization, and knowledge mobilization. It was designed to support visionary clinician–scientists whose work bridges scientific discovery and patient care, while helping to strengthen UHN's leadership in translational research, clinical innovation, commercialization, and knowledge mobilization.

“Initially designed to support only one award, the exceptional caliber of these two applicants motivated SUMO and the Canada Leads program to double their commitments and recognize both awardees,” says Dr. Paul Tenenbein, Chair of SUMO. “This demonstrates the research excellence among our physicians at UHN, and their dedication to advancing the development of novel, high-impact approaches to healthcare delivery. SUMO is pleased to partner with UHN on this award, and hope that it serves as a model for future opportunities to support academic physicians.”

• Related: Read more about SUMO’s impact “Powering Physician Innovation | UHN Research”

A key focus of the award is supporting mid-career researchers, who play a vital role in driving innovation and mentoring the next generation of scientists but often have fewer dedicated funding opportunities. “By investing in researchers at this pivotal stage in their careers, the award helps them expand the scope and impact of their work while strengthening UHN's long-term research capacity and leadership,” says Dr. Brad Wouters, Executive Vice President of Science & Research at UHN. “It also creates the conditions for bold ideas to move more quickly from the laboratory and clinic into real-world solutions that benefit patients and health systems alike, reflecting a core goal of the Canada Leads program and UHN's unique opportunity to translate made-in-Canada discoveries into global impact.”

Drs. Bhat and Howe will each receive $500,000 over five years to dedicate more time to research that can transform patient care and generate long-term impact for the health system. As the co-recipients of this award, Drs. Bhat and Howe exemplify the excellence of UHN’s world-class research community, and the dedication that it has towards tackling complex health care challenges through interdisciplinary and collaborative science. Congratulations to Drs. Bhat and Howe.

For more information on SUMO’s commitment to supporting academic physicians, visit the SUMO website.

Research Spotlight

Read the latest bi-monthly newsletter that highlights advancements from UHN researchers.

Welcome to the latest issue of Research Spotlight.

As Canada’s largest research hospital, UHN is a national and international source for discovery, education, and patient care. This newsletter highlights top research advancements from over 5,000 members of TeamUHN—a diverse group of trainees, staff, and principal investigators who conduct research at UHN.

Stories in this month’s issue:

● A New Avenue for Bipolar Depression: Researchers report rapid symptom relief with repeated ketamine infusions.

● Assessing Kidney Disease Globally: Kidney disease worsens outcomes for patient hospitalized with cirrhosis; study finds.

● Unlocking Therapeutic Potential: Establishing a new AI tool to identify cancer-responsive T cell receptors.

● Retaining a Vital Nursing Workforce: Clearer roles and stronger career support could help retain registered practical nurses.

Read these stories and more online here. To read previous issues, see the newsletter archive.