A novel method for boosting the T-cell immune response utilizing messenger RNA (mRNA) vaccines has been devised by engineers at the Massachusetts Institute of Technology. The researchers posit that this technology holds the potential to enhance the efficacy of anti-cancer treatments and bolster the body’s defense against infectious diseases.
The core of this innovation lies in the incorporation of specialized immunomodulatory mRNA molecules. Experiments conducted on mice demonstrated that employing this technology not only significantly retarded tumor growth but, in certain instances, resulted in complete tumor eradication.
Conventional vaccines typically stimulate the production of both antibodies and T-cells capable of recognizing antigens. This new study, however, focused specifically on augmenting the T-cell response through the introduction of a new type of adjuvant—a substance designed to heighten the immune system’s activity. To achieve this, mRNA molecules coding for the IRF8 and NIK genes were utilized.
According to Professor Daniel Anderson of Chemical Engineering, these molecules activate immune signaling pathways, shifting immune system cells into a more active state. This results in an increase in the population of T-cells specifically targeted against the given antigen. The researchers emphasized that these particular cells are crucial for eliminating virus-infected tissues and cancerous cells.
Specialists from Harvard Medical School and Massachusetts General Hospital also contributed to this research. The scientists noted that existing cancer vaccines have already shown promising outcomes, with some agents receiving FDA approval for treating specific types of cancer. Nevertheless, in some patients, the resulting immune response remains insufficient to fully eliminate the malignancy.
To circumvent the hazardous side effects associated with cytokine administration, the researchers opted to directly influence the internal signaling mechanisms within the immune cells. The NIK enzyme triggers pathways responsible for immunity and inflammatory responses, while IRF8 aids in programming cDC1-type dendritic cells, which are exceptionally effective at activating T-cells.
Lipid nanoparticles, structurally similar to those used in COVID-19 vaccines but chemically modified, were employed for delivering the mRNA molecules. Following intravenous administration, these particles preferentially accumulated in the spleen, engaging with antigen-presenting cells.
Within just 24 hours after injection, the cells began producing IRF8 and NIK, initiating their activation and maturation. Over the subsequent few days, the count of T-cells markedly increased, subsequently leading them, alongside other immune cells, to target the tumors.
The technology was evaluated across mouse models featuring aggressive bladder cancer, melanoma, colorectal carcinoma, and metastatic lung cancer. In nearly all test cases, a pronounced enhancement of the T-cell response and retardation of tumor growth were observed; moreover, in a number of experiments, the tumors vanished entirely.
Furthermore, the new technology amplified the effectiveness of immune checkpoint inhibitors—drugs designed to release the blockades that tumors place on T-cells. Researchers also tested the platform in conjunction with vaccines for coronavirus infection and influenza. Their findings indicated that in mice, the T-cell response was boosted tenfold to fifteenfold compared to standard vaccination protocols.
The team is currently proceeding with trials on other animal models and anticipates adapting this platform for human application in oncology and the treatment of infectious diseases in the future.
About the Author
