Adjuvant Development Services

Immunologic adjuvant, also known as immunomodulator or immunopotentiator, can enhance and modulate the immune responses triggered by antigens. As an additive to vaccines, adjuvants elicit potent immune responses, often allowing lower vaccine doses and prolonged efficacy. The ideal adjuvants can boost the immune response and enable the body to obtain the best protective immunity. In general, adjuvants belong to non-specific immunopotentiator without antigenicity. There are several major modes of action, including immune regulation, induction of cytotoxic T lymphocyte, antigen presentation, antigen targeting and storage among others.

Potential benefits of utilizing adjuvants

• Reduction of vaccine dose and frequency
• Vaccine response augment and broadening
• Accelerating vaccine response
• Overcoming immune senescence

Strategies to develop adjuvants for mRNA vaccines

As a new generation of medicines, mRNA-based vaccines have emerged as promising alternatives to conventional vaccine approaches. The addition of adjuvants is an emerging trend for developing safe and improved mRNA vaccines. The immunostimulatory properties of mRNA were reported to be potentiated by the addition of an adjuvant, thus, enhancing the potency of some mRNA vaccine formats. Protein adjuvants involve small molecular peptides or glycoproteins, a class of bioactive substances secreted and synthesized by immune cells and some non-immune cells via stimulation. They play an important role in T cell differentiation, and can enhance the function of NK cells, T lymphocytes, to widely increase the body's immune response. Among them, granulocyte–macrophage colony-stimulating factor (GM-CSF), also known as colony-stimulating factor 2 (CSF2), is a monomeric glycoprotein secreted by multiple immune cells and functions as a cytokine. GM-CSF is a supplement of an mRNA vaccine and has already been tested in clinical trials. In addition, several mRNA delivery vectors also show the adjuvant effect, such as protamine and cationic lipid.

The combination of mRNA and protamine.
(Pardi, N., et al, 2018).

The strategies to develop adjuvant for mRNA vaccines include traditional adjuvants, such as MF59 (Novartis) adjuvant, GM-CSF and cationic nanoemulsion (CNE), as well as novel methods that take advantage of mRNA’ intrinsic immunogenicity or its ability to encode costimulatory molecules, involving CD40L, CD70, OX40L and so on.

Addition of conventional adjuvants

• The discovery and characterization of adjuvant candidates
• Structural alterations of adjuvants
• Development of novel adjuvant combinations
• Evaluation of safety profile, immunologic profile of activity, immunotoxicity

Novel strategies of adjuvant development for mRNA vaccine

• Design and production of self-adjuvanticity mRNA
• Design and production of mRNA encoding adjuvant molecule

Apart from optimization of mRNA and its delivery system, the addition of adjuvants presents another optimizing strategy to enhance and broaden the function of mRNA vaccines. If you are interested in our service, please contact us for more information!