Duane Mitchell

Activates T-Cell Recognition of Tumor-Initiating Stem Cells in Mouse Model of Glioma

This nanoparticle vaccine targets the slow-cycling, treatment-resistant, cancer stem cells to improve efficiency of anti-cancer drugs, thereby improving disease prognosis. Despite major developments in the field of anti-cancer therapies, tumor recurrence and metastasis after chemotherapy is still the major cause of cancer patient mortality. Although current RNA-lipid nanoparticle (NP) vaccines have shown promising results, they still remain encumbered by profound intra-tumoral and systemic immunosuppression. Because of the heterogeneity of cancer epitopes, a major challenge in the field of vaccine development is determining the best target. Studies carried out by our researchers at the University of Florida have demonstrated that recurrences in gliomas can be attributed to the subset of slowly dividing cells, resistant to conventional anti-cancer therapies. These slowly dividing cells exhibit enhanced tumorigenicity and infiltrative propensity. Hence, clinical strategies targeting this specific population of cancer cells holds great potential in improving therapeutic efficiency of drugs.

To address this issue of cancer recurrence, our scientists have developed a universal RNA-NP vaccine engineered with RNAs for epitopes specific to slow-cycling tumor cells, as well as a personalized RNA-NP vaccine engineered from RNA extracted from patient’s tumor biopsy. These vaccines are able to activate T-cell recognition of slow-cycling tumor-initiating stem cells mediating sustained anti-tumor activity in the mouse model of glioma.

Application

Nanoparticle vaccine for either personalized or universal treatment of cancer

Advantages

• Can be engineered using relevant tumor antigens, creating a universal RNA-NP vaccine to target treatment-resistant, slow-cycling cancer cells
• Can be engineered with RNA extracted from patient’s tumor biopsy, creating personalized RNA-NP vaccines
• Increased efficacy and specificity, generating robust and expeditious anti-tumor response
• Overcomes intra-tumoral and systemic immunosuppression, priming the system to respond better to immunotherapy

Technology

This therapeutic platform demonstrates the use of two different nanoparticle (NP) vaccines (personalized and universal) engineered with RNA derived from a specific subpopulation of slow-cycling, tumor-initiating stem cells. These immunomodulating vaccines are able to elicit T-cell response against slow-cycling, tumor-initiating cancer stem cells, leading to sustained anti-tumor activity. Researchers found that systemic administration of this vaccine primes the peripheral and intra-tumoral microenvironments for response to immunotherapy. These RNA-NPs localize to heart, lung, bone marrow, spleen, liver, kidney and subcutaneous/intracranial tumors. In immunologically resistant tumor models (i.e. B16F0, B16-F10, Lewis lung carcinoma) resistant to immune checkpoint inhibitors, these RNA-NPs activate the preponderance of systemic and intra-tumoral antigen presenting cells (characterized by co-expression of PD-L1 and CD86) for induction of anti-tumor immunity. Altogether, this therapeutic platform delivers specific sets of tumor RNA antigens purified from slow-cycling cancer stem cells to create personalized or universal vaccines.

Encodes for Specific Antigens to Promote Anti-Tumor Immunity

This cancer vaccine activates antigen-presenting cells and induces anti-tumor immune system activity for the treatment of diffuse intrinsic pontine gliomas (DIPG). DIPG tumors originate in the pons, an area of the brainstem controlling vital body functions such as breathing and heart rate. DIPG is the main type of brain tumor causing death in children, and it comprises 10-20 percent of all pediatric brain tumor cases. The widely spread nature and location of these tumors prevent early diagnosis, which greatly limits treatment options. Surgical resection is not possible due to the tumors’ location, and chemotherapy has not been successful at treating DIPG. Radiation therapy has been able to shrink tumor size, but this effect is typically short-lived and does not cure patients. Diagnosing patients with DIPG usually occurs between the ages of 5 and 9, and their median survival rate is 10-11 months.

Researchers at the University of Florida have developed a vaccine that treats DIPG by driving anti-tumor immunity. The global RNA therapeutics and vaccine market is expected to surpass $800 million by the end of 2029. This RNA vaccine delivers liposomal nanoparticles by intravenous injection that activate specific antigen-presenting cells to increase immunogenicity against DIPG. Improved survival rates in animal models have demonstrated the vaccine’s success.

Application

An off-the-shelf vaccine for the treatment of diffuse intrinsic pontine glioma (DIPG)

Advantages

• Produces DIPG tumor-specific antigens to induce immunogenicity, priming the environment for successful immunotherapy
• RNA-based vaccine, minimizing cost and production time while reducing toxicity compared to traditional treatments

Technology

This RNA vaccine targets a homogenously expressed diffuse intrinsic pontine glioma (DIPG) tumor antigen, allowing for widespread use without the need for customized treatment. The RNA renewably encodes specific DIPG antigens to continuously vaccinate the patient, increasing central memory T-cell levels for sustained anti-tumor immunity. A liposomal nanoparticle delivers the vaccine to prevent RNA degradation.

Creates Precise Multicellular 3D Structures Needed for Experiments in Diverse Research Areas

This micro-biofabrication system combines computer vision, robotics, micromanipulation tools, and a novel culture medium to enable the creation of optimized 3D cellular structures. A level of exquisite detail exists in the intricate pattern and spatial structure of cells found in developing tissue. Micromanipulation tools allow precise translation and placement of single cells. However, available bioprinting systems cannot employ these tools to build highly intricate multicellular 3D structures in a cell-by-cell manner. They cannot hold the deposited cells in place while building structures without creating misconfigured layers or dispersed single cells. Researchers in many fields need effectively perfect multicellular 3D structures to understand topics like embryonic development, function-form relationships, immune signaling, and drug screening for efficacy and toxicity.

Researchers at the University of Florida have developed a cellular micro-masonry system that enables the microfabrication of highly intricate 3D cell structures. A 3D printing culture medium supports cellular structures as they are built one cell at a time using micromanipulation techniques and real-time imaging.

Application

A bioprinting system that builds perfect 3D structures cell by cell

Advantages

• Holds deposited cells in place, allowing one to build precise multicellular structures
• Creates various cell and tissue models, providing opportunity for drug testing and toxicity screening

Technology

This cellular micro-masonry system integrates a cell translation system, an imaging system, and a 3D culture medium. The culture medium that supports the 3D construction of cells is a liquid-like solid made from jammed microgels swollen in liquid growth media. Through micromanipulation and cell aspiration performed within this culture medium, the system retrieves dispersed cells one at a time, translates them to the building area, and places them at the desired location in 3D space. The system is mounted on a fast-scanning multi-photon microscope to enable real-time tracking of cells, path corrections, and structural refinements during the building process.

Increase Migration and Immune Response with Sarcosine-Loaded Dendritic Cells

These sarcosine-loaded dendritic cells exhibit enhanced migration to local lymph nodes, increasing the stimulation and migration of T-cells for cancer treatment. Immunotherapy has become a popular approach to treat cancer in recent years. A particular approach is providing patients with a vaccine of their own dendritic cells that presents a particular tumor antigen. University of Florida researchers have developed dendritic cells loaded intracellularly with sarcosine. Sarcosine, also known as N-methylglycine, is a metabolite of an amino acid found naturally in biological tissues; it is easily acquired from a variety of companies. The dendritic cells containing sarcosine have shown to significantly improve dendritic cell migration, in turn increasing stimulation of an immune response, resulting in the tumor being attacked and killed. Using dendritic cells for tumor treatment has already been approved by the FDA in prostate cancer and is currently in phase III clinical trials for other forms of cancers.

Application

Sarcosine-loaded dendritic cells used for adoptive immunotherapy increases immune response and potentially survival rate of cancer patients

Advantages

• Increases efficacy of dendritic cell vaccination, enhancing adoptive T cell transfer
• Creates robust immune response, potentially improving survival in patients with cancer
• Uses patients own dendritic cells, decreasing unwanted immune response

Technology

Dendritic cells act as antigen presenting cells (APCs), presenting antigens to T-cell receptors. One immunotherapy approach to treating cancer provides patients with a vaccine of their own dendritic cells loaded with tumor antigens. Those dendritic cells migrate to a lymph node where they simulate T cells to generate an immune response, allowing the cells to express the target antigen that results in tumor killing. Enhancing that migration of dendritic cells to the local lymph node is critical for efficacy of this treatment strategy. University of Florida researchers have discovered that loading those dendritic cells with sarcosine, a common metabolite, significantly improves migration to local lymph nodes compared to previous strategies. This sarcosine addition for treatment can be applied to other cells such as T-cells in an adoptive immunotherapy strategy. This intracellular sarcosine loading method also has the potential to enhance migration of T-cells and stem cells allowing this treatment to be applicable in other diseases.

Modulates Patient's Immune System to Reduce Lewy Body Protein Aggregates

This therapeutic vaccine treats Lewy body diseases, such as Parkinson’s disease, by clearing misfolded protein aggregates utilizing a patient's own immune system. An estimated 1.4 million people in the U.S. suffer from Lewy body dementia, making it the second most frequent form of degenerative dementia in the country. However, Lewy body diseases often go misdiagnosed until patients present symptoms associated with moderate or severe stages of the disease. Incorrectly prescribed medications due to misdiagnosis further worsens the disease state, potentially resulting in death. Available treatments for Lewy body diseases include a peptide-based vaccine under clinical trial investigation. However, the use of peptide and related antibody-inducing vaccines runs the risk of prompting an auto-immune response in the patient. Other treatment options for these diseases provide only symptomatic relief that wears off as the disease progresses and does nothing to prevent further neurodegeneration.

Researchers at the University of Florida have developed an adoptive cellular therapy vaccine that makes use of the patient’s own cellular immunity to reduce the misfolded protein aggregates characteristic of Lewy body diseases, providing treatment by inhibiting future neurodegeneration. Since this vaccine does not involve the use of antibodies, the chance of patients experiencing an auto-immune response decreases.

Application

Adoptive cellular therapy vaccine that treats Lewy body diseases with lessened risk of auto-immune response

Advantages

• Clears misfolded alpha synuclein in the brain and spinal cord, reducing the presence of Lewy bodies to inhibit future neuronal cell death
• Harnesses the patient’s immune system to clear protein aggregates, eliminating the need for external peptide antigens
• Utilizes adoptive cellular therapy, decreasing the likelihood of patient auto-immunity
• Targets only cells infected with mutant misfolded proteins, providing specificity of treatment

Technology

This adoptive cellular therapy involves taking T cells from the patient’s body, exposing them to an alpha-synuclein mutant antigen, and administering the T cells back into the patient’s body. This grants the patient’s immune system the ability to specifically target cells containing the misfolded alpha-synuclein aggregates and clear them from the body, preventing accumulation of the mutant proteins.