Pre-Transplant Treg Expansion Therapy Shows Promise for Reducing GVHD Risk in Blood Cancer Patients
核心洞察
Researchers at Sylvester Comprehensive Cancer Center (搜索) developed a novel protocol using TL1A-Ig fusion protein (搜索) and low-dose IL-2 to expand regulatory T cells (搜索) before stem cell transplant, demonstrating improved survival rates and reduced GVHD severity in preclinical studies.
The therapy works by stimulating the patient's own immune system to create a safer transplant environment while maintaining graft-versus-leukemia activity, offering an alternative to broad immune suppression.
Preclinical results showed higher survival rates, better tissue integrity, and a more diverse gut microbiome, with the protocol working entirely in vivo to expand Tregs in key organs like the colon, liver, and eyes.
Researchers at the Sylvester Comprehensive Cancer Center (搜索), part of the University of Miami Miller School of Medicine, have developed a promising new approach to make allogeneic hematopoietic stem cell transplantation (aHSCT) safer for blood cancer patients. The study, published on the cover of the November 27, 2025 issue of Blood, demonstrates that priming the immune system with regulatory T cell (Treg)-expanding therapy before transplant can significantly improve outcomes while reducing the risk of graft-versus-host disease (搜索) (GVHD).
Novel Protocol Targets Immune Regulation
Led by senior author Robert Levy, Ph.D., a researcher at Sylvester and professor of microbiology and immunology at the Miller School, the multi-institutional research team developed a protocol that uses targeted immunotherapy to expand the body's own regulatory T cells (搜索) before transplant. Unlike traditional approaches that rely on broad immune suppression, this strategy focuses on strengthening the patient's natural immune regulation.
"Our approach is about helping the patient's own immune system create a safer environment for the stem cell transplant," Levy explained. "We're not just suppressing the immune response—we're guiding it in key tissues involved following the transplant to promote success."
The researchers used a combination of two agents: TL1A-Ig fusion protein (搜索) and low-dose IL-2. These agents stimulate specific receptors (TNFRSF25 (搜索) and CD25 (搜索)) on Tregs, encouraging them to multiply and become more active. The expanded Tregs were found to migrate to key tissues such as the colon, liver, and eye—areas commonly affected by GVHD.
Promising Preclinical Results
The preclinical studies demonstrated several significant benefits of the Treg expansion protocol:
- Higher survival rates after transplant
- Lower GVHD scores and less weight loss
- Better tissue health and integrity
- A more diverse and healthy gut microbiome
"We saw that expanding Tregs before transplant helped protect vital tissues organs and supported a healthier microbiome," Levy said. "This could mean fewer complications and better recovery for patients."
Importantly, the protocol did not interfere with the body's ability to address cancer cells—a process known as graft-versus-leukemia (GVL). Maintaining GVL activity is crucial for preventing relapse in patients with blood cancers (搜索).
Addressing Current Treatment Limitations
Allogeneic hematopoietic stem cell transplantation is a vital treatment for many blood cancers (搜索) and other serious conditions, but it carries the potentially fatal risk of GVHD, where donor immune cells attack the patient's tissues. Standard care typically relies on powerful immune-suppressing drugs to prevent GVHD, but these medications can cause side effects and leave patients highly vulnerable to infections.
"Our goal is to make transplants safer while still allowing the patient's immune system to do its job against cancer," Levy noted. "We're working toward therapies that are both effective and practical for real-world use."
Simplified, Accessible Treatment Approach
Unlike older methods that require collecting and manipulating donor cells outside the body, Levy's protocol works by expanding the patient's own Tregs in vivo—inside the body—before the transplant. This approach could simplify treatment, lower costs, and make it more widely accessible.
The research also highlights the important role of the gut microbiome in transplant outcomes. Patients who received the Treg expansion protocol had a more diverse and balanced microbiome, a finding that is increasingly recognized as important for immune health.
"Personalized medicine is about tailoring treatments to each patient's needs," Levy said. "By supporting the immune system and microbiome, we can help patients recover more smoothly."
Moving Toward Clinical Translation
The research team, which included collaborators from Sloan Kettering Institute and Memorial Sloan Kettering (搜索) in New York, Weill Cornell Medical College, and Fred Hutchinson Cancer Center in Seattle, is now working to translate these findings into clinical trials. The hope is that this protocol will become part of standard care for patients undergoing stem cell transplants, leading to fewer complications and better long-term outcomes.
"We're excited to continue this work and collaborate with clinicians to bring new therapies to patients," Dr. Levy concluded. "Every step forward brings us closer to safer, more effective transplants."