Scientists Creating mRNA Biologics with Added Aluminum Adjuvant

Scientists at Boston Children’s Hospital in Massachusetts have developed an experimental mRNA biologic technology that they say produced longer-lasting immune responses in animal studies without the use of additional booster shots. The 2026 study was published in Nature Immunology.¹

The research looked at a challenge in mRNA technology on how to make protection last longer over time. Current mRNA biologics often require additional booster doses because immune responses weaken months after administration and virus variants keep evolving. According to the study, the research team investigated whether changing how the biologic travels through the body could extend the immunity period after a single dose.²

Testing of mRNA COVID-19 Biologic With Aluminum Adjuvant

The study paired the original COVID-19 mRNA biologic with an adjuvant, a substance used to trigger the body’s immune response. The research team developed the adjuvant using mannan, a branched sugar molecule found on the outer cell wall of Candida yeast. Researchers combined the mannan with aluminium hydroxide, a commonly used vaccine adjuvant, to create what they called “mannadjuvant.”³

The researchers explained that mRNA biologics contain genetic instructions for producing part of the virus spike protein inside immune cells. These instructions are enclosed in a fatty outer coating designed to help deliver the biologic into cells. The research team first tested whether the biologic remained stable after being combined with the adjuvant before studying its immune effects.⁴

Rather than altering the genetic instructions carried by the biologic, the scientists modified the delivery system surrounding the mRNA. The biologic was engineered to bind to albumin, a protein that naturally circulates in the bloodstream. They said this approach helped direct more of the biologic into lymph nodes, which are key centers of immune system activity.⁵

Lymph nodes help the body coordinate immune responses by bringing immune cells into contact with foreign materia/pathogens. According to the study, conventional mRNA biologics do not always reach these tissues efficiently because much of the injected material remains near the injection site. The new modified biologic was designed to improve movement into the lymphatic system and prolong immune system exposure to components of the mRNA biologic.⁶

In animal studies, the researchers reported that the modified biologic generated stronger and more sustained antibody responses than standard mRNA biologics. The study also found increased activity in germinal centers, structures inside lymph nodes that help the body produce immune memory cells and refine antibodies. Researchers said these immune responses lasted longer during the observation period used in the study.⁷

Study Explores Effects on Immune Cells

The researchers also examined CD8+ T (cytotoxic) cells, which help identify and destroy infected or abnormal cells. According to the study, animals that received the modified biologic showed stronger CD8+ T-cell responses than those given conventional mRNA biologics. The authors of the study stated that these findings may be relevant to future research involving infectious diseases and therapeutic cancer vaccines.⁸

Researchers said reducing the need for booster shots could affect how mRNA biologics are distributed and administered with fewer booster doses and that could change the logistics of vaccination campaigns.  However, they also stated that the findings remain preliminary and have not yet been tested in humans.⁹

The authors reported that the study was preclinical and that further research will be necessary to determine safety, effectiveness, and durability in human populations. Future studies are expected to examine how the biologic platform performs with different diseases and vaccine targets.¹⁰

Studies on aluminum-based vaccine adjuvants have documented severe adverse effects that cause brain and immune dysfunction^11 12 13 and researchers say further study is needed to determine how combining aluminum adjuvants with newer mRNA biologic platforms could affect long-term safety and immune responses. Studies on the mRNA technology used to develop the COVID biological, which manipulates cell function to stimulate production of a synthetic spike protein that, along with mRNA and lipid nanoparticles, remains in the body for an undetermined amount of time and calls into question the safety of mRNA technology as a basis for creating preventive health care products.¹⁴

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