The central challenge tackled by this research lies in the immunosuppressive nature of myeloid cells—immune cells abundant within glioblastoma tumors—that often dampen the body’s natural anti-cancer responses. These myeloid cells form a protective milieu that enables residual cancer cells to evade destruction after surgical excision, contributing to tumor recurrence. The research team asked whether reprogramming these immune cells immediately after tumor resection could convert this suppressive environment into a pro-inflammatory, cancer-fighting one.

To achieve this, the investigators engineered a wafer-like implant made of crosslinked cyclodextrin, a sugar-based, biodegradable polymer capable of sustained drug release. This implant, aptly nicknamed CANDI, is designed to be placed in the brain cavity created after tumor removal surgery. Its slow-release mechanism delivers a potent cocktail of small molecule immune modulators directly to the myeloid cells infiltrating the surgical site. By precisely targeting myeloid cells in situ, the wafer aims to enhance local immune activation without systemic toxicity.

Initial in vitro experiments confirmed that the cyclodextrin wafer not only successfully released the immune-modulating agents but was also effectively engulfed by tumor-associated macrophages—key myeloid cells in glioblastoma. Upon internalization, these immune cells were reprogrammed to produce interleukin-12 (IL-12), a cytokine critical for stimulating robust anti-tumor immunity. IL-12 promotes the recruitment and activation of cytotoxic T cells, boosting the immune system’s ability to eradicate remaining glioblastoma cells.

In vivo studies in mouse models of glioblastoma provided compelling evidence for the wafer’s efficacy. When implanted following surgical tumor removal, CANDI resulted in long-term tumor-free survival in over half of the mice treated, a remarkable improvement compared to controls. Immune profiling confirmed increased infiltration and activation of T cells at the tumor site, validating the immune-modulating strategy’s ability to transform the tumor microenvironment from immunosuppressive to immunostimulatory.

Crucially, the team extended their investigations to freshly harvested human glioblastoma tissues maintained ex vivo, demonstrating that the wafer induced similar immunological changes in human tumors. This translational aspect strengthens the potential clinical relevance of the implant-mediated therapy and signals feasibility for eventual human trials.

This breakthrough holds substantial implications for the future of glioblastoma treatment. While immunotherapies have revolutionized management of various cancers, no FDA-approved immunotherapy yet exists for glioblastoma due to its highly immunosuppressive microenvironment and poor drug delivery across the blood-brain barrier. By directly implanting an immunomodulatory device into the surgical cavity, this approach circumvents systemic delivery challenges and may complement existing standards of care, such as chemo- and radiotherapy, potentially extending patient survival and improving quality of life.

Looking ahead, the researchers are focused on refining the wafer’s design to optimize drug release kinetics for human applications and scaling up production consistent with clinical manufacturing standards. They are preparing to enter phase I clinical trials, with the goal of integrating this implantable immunotherapy into surgical oncology protocols in the near future.

The publication credits Christopher S. Garris, Hyung Shik Kim, Juhyun Oh, Elias A. Halabi, Moonhyun Choi, Sepideh Parvanian, and Rainer Kohler as co-authors, emphasizing the collaborative interdisciplinary efforts that made this innovation possible. Financial support was provided by grants from the National Institutes of Health, as well as the Swiss Institute for Experimental Cancer Research and the German Academic Exchange Service.

This pioneering strategy exemplifies how converging advances in biomaterials, immunology, and neurosurgery can yield transformative therapies for some of medicine’s most intractable diseases. If successful in human trials, the CANDI implant could mark a paradigm shift in glioblastoma management, leveraging the body’s own immune arsenal to prevent cancer relapse in a disease that has long defied durable control.

Such implant-mediated immunotherapies may soon extend beyond glioblastoma to other solid tumors characterized by immunosuppressive microenvironments, broadening the therapeutic impact of this novel modality. As this research progresses, it reinforces the critical role of local immune modulation in enhancing cancer control and the promise of biomaterials to precisely deliver such interventions.

This study stands at the forefront of personalized medicine, transforming the surgical bed from a vulnerable site of residual disease into a battleground of immune-mediated tumor eradication. The innovation paves the way for integrating immunotherapy directly into surgical practice, potentially revolutionizing outcomes for patients afflicted by devastating cancers like glioblastoma.

Subject of Research: Animals
Article Title: Targeting immunosuppressive myeloid cells via implant-mediated slow release of small molecules to prevent glioblastoma recurrence
News Publication Date: 22-Oct-2025
Web References: DOI: 10.1038/s41551-025-01533-2
References: Kaiser, Y., et al. Nature Biomedical Engineering, 2025
Image Credits: Not provided

Mass General Brigham’s Gene and Cell Therapy Institute, established in 2022, is a beacon of translational research that amalgamates the expertise of over 500 scientists and clinicians focused on charting new territories in genetic medicine. Their commitment to pioneering therapeutic modalities that transition from bench to bedside has been highlighted through a series of compelling presentations that showcase novel delivery systems, engineered vectors, and sophisticated cellular platforms capable of targeting diseases at the molecular and cellular levels.

Among the standout presentations is the study on optimizing focused ultrasound (FUS) parameters to enhance adeno-associated virus (AAV) vector delivery across the notoriously impermeable blood-brain barrier (BBB). The impermeability of the BBB has long posed a formidable challenge in delivering gene therapies to the central nervous system, restricting therapeutic efficacy. Researchers led by Bernie Owusu-Yaw, PhD, demonstrated that transient BBB opening with focused ultrasound coupled with microbubbles dramatically increased neuronal transduction without causing tissue damage. Intriguingly, their results suggest the complexity of BBB dynamics as the volume of barrier opening did not directly correlate with gene delivery efficiency, pointing to nuanced biological mechanisms that govern viral vector penetration.

In a complementary domain, Elie Roumieh, MD, presented a sophisticated human cell-based platform developed to test olfactory ensheathing cells (OECs) as vectors for cancer gene therapy targeting gliomas. OECs’ unique migratory capacity and natural affinity for CNS tumor sites position them as promising candidates for delivering therapeutic transgenes directly to malignancies. Using hiPSC-derived brain-glioma assembloids—a co-culture system combining human cerebral organoids with glioma cells—the research team successfully depicted extensive tumor invasion and validated OEC identity via markers like p75NGFR and MPZ. These culture systems offer unprecedented human-relevant models for dissecting OEC-tumor interactions and potentiating cell-based targeted therapies.

Aarushi Gandhi, PhD, shed light on the pathophysiology and treatment potential for Multisystemic Smooth Muscle Dysfunction Syndrome (MSMDS), a crippling monogenic disorder caused by mutations in the ACTA2 gene. Their innovative murine model harbored a conditional R179H knock-in mutation replicating the human disease phenotype, including vascular shear stress and neurological deterioration due to BBB disruption. Strikingly, by leveraging CRISPR-Cas9 adenine base editing delivered via AAV vectors, the group reversed the ACTA2 mutation in vivo. Restoration of smooth muscle functionality correlated with reduced BBB permeability and attenuation of neurodegenerative processes, demonstrating a promising gene-editing therapeutic avenue to tackle ultrarare genetic vascular disorders.

Mass General Brigham researchers also introduced the RISE framework—proposed by Nandhitha Uma Naresh, PhD—to overcome translational bottlenecks that academic medical centers (AMCs) frequently encounter in advancing cell and gene therapies (CGTs). RISE advocates for four critical pillars: Resource sharing, Interdisciplinary collaboration, Sustainable funding, and Educational outreach. This strategic model underscores the necessity for comprehensive institutional support beyond mere funding, aiming to bridge the translational valley of death that hinders many innovative academic therapies from reaching clinical application.

Nick Todd, PhD, expanded upon the FUS paradigm with compelling preclinical evidence demonstrating the clinical translatability of combining focused ultrasound with a novel engineered AAV capsid, AAV.CPP16. This engineered capsid incorporates cell-penetrating peptides to enhance BBB penetration and neuronal tropism. Using a state-of-the-art human clinical FUS system, they successfully delivered the vector systemically in both rat and non-human primate (NHP) models. MRI-guided sonication with real-time feedback allowed precise opening of deep brain regions without hemorrhagic complications. The observed robust neuronal transduction at remarkably low viral doses bolsters the promise of this minimally invasive platform for treating neurological diseases with high spatial precision and safety.

On the pulmonary front, Yan Tang, PhD, unveiled pioneering gene replacement strategies for pulmonary lymphangioleiomyomatosis (LAM), a rare disease driven by mutations in tumor suppressors TSC1 or TSC2 leading to mTORC1 hyperactivation. Current FDA-approved treatments like sirolimus attenuate progression but fail to halt disease entirely, with many patients ultimately requiring lung transplantation. Utilizing lipid nanoparticle (LNP) technology to deliver functional mouse Tsc2 mRNA in a preclinical model, researchers accomplished significant tumor burden reduction. This LNP-based mRNA therapy restores tumor suppressor activity at the cellular level, highlighting a scalable therapeutic platform that could potentially revolutionize treatment for LAM and similar monogenic pulmonary conditions.

The collective advances presented at ASGCT 2025 epitomize a paradigm shift in gene and cell therapy, where multipronged approaches—including mechanical techniques like FUS, genetic correction via CRISPR base editing, and innovative cellular vector platforms—coalesce to overcome biological barriers long deemed insurmountable. Mass General Brigham’s concerted focus on rare and ultrarare diseases further underscores the commitment to addressing neglected patient populations with high unmet need, forging pathways toward durable, curative solutions.

Beyond the scientific breakthroughs, the institute’s strategic vision and collaborative ecosystem are pivotal in catalyzing these innovations. By integrating clinical research, preclinical modeling, and advanced biotechnology, Mass General Brigham leverages the confluence of cutting-edge science and translational medicine. Their presentations at the ASGCT meeting not only showcase the feasibility and safety of sophisticated gene therapy delivery systems but also lay the groundwork for future clinical trials that will bring these promising therapies closer to real-world implementation.

In sum, the ASGCT 2025 presentations from Mass General Brigham reveal how advanced gene editing, novel vector engineering, non-invasive targeting strategies, and robust cellular platforms are transforming the therapeutic landscape. These innovations carry the potential to significantly improve patient outcomes across a spectrum of debilitating genetic and degenerative diseases, signaling a new era where the integration of gene and cell therapies will become a mainstay of personalized medicine.

Subject of Research: Gene and cell therapy advancements targeting neurodegenerative diseases, brain cancer, rare genetic syndromes, and pulmonary lymphangioleiomyomatosis (LAM).

Article Title: Pushing the Frontiers of Gene and Cell Therapy: Mass General Brigham’s Breakthrough Research Unveiled at ASGCT 2025

News Publication Date: 2025 (May 13-17)

Web References:

• Mass General Brigham — https://www.massgeneralbrigham.org/en
• ASGCT Annual Meeting Abstracts — https://annualmeeting.asgct.org/abstracts
• Dropbox link to abstracts (provided in source content)

Keywords: Gene editing, Gene delivery, Medical treatments, Gene therapy, Focused ultrasound, Blood-brain barrier, CRISPR base editing, AAV vectors, Olfactory ensheathing cells, Pulmonary lymphangioleiomyomatosis, Lipid nanoparticle mRNA therapy, Cell and gene therapy innovation