YAD Nanoemulsion Adjuvant Optimization Service

Overview of Emulsion Adjuvant

Emulsions have been employed as vaccine adjuvants for since long, but we had to wait until the final years of the last century to have them approved for human use. This happened because the mineral oils used in the first-generation adjuvanted vaccines were not metabolizable and, despite being strong potentiators of the antibody response, they caused aseptic abscesses which were not resorbed. The development of oil-in-water emulsions such as MF59 and adjuvant systems based on emulsions such as AS03, using fully metabolizable oils, resolved this issue and first allowed the development of improved seasonal inactivated vaccines against influenza.

Fig. 1. Chemical structure of
squalene. (Montana, 2010)

• Squalene

The common component of oil-in-water emulsions is squalene, a fully metabolizable lipid synthesized by the human body along the pathway of cholesterol synthesis Squalene is a linear hydrocarbon precursor of cholesterol found in many tissues, notably the livers of sharks (Squalus) and other fishes. The richest natural source of squalene continues to be from deep-sea shark livers. Unfortunately, due to overfishing and increased pollution in the ocean that can contaminate the triterpene product, shark-derived squalene is an unfavorable source for medical applications.

• Botryococcene

Botryococcene is a typical lipid that is naturally produced only by the green algae, Botryococcus braunii, which has specific races. Botryococcus braunii is a green colonial microalga widespread in freshwater and brackish lakes, reservoirs, ponds, or even ephemeral lakes situated in continental, temperate, alpine, or tropical zones. This alga is characterized by a conspicuous ability to synthesize and accumulate a variety of lipids. Botryococcene is an isomer of squalene that is generated when the two precursor molecules. However, the resistance to extraction, and the mixture of chemically similar triterpene oils - which would require laborious purification to obtain large amounts of individually pure triterpenes - all make it a less desirable source.

YAD Nanoemulsion Adjuvants

YAD nanoemulsion adjuvants are yeast-produced squalene, botryococcene. YAD-S uses the canonical triterpene, squalene, as the lipid component. YAD-B uses the non-native triterpene, botryococcene, as the lipid component. The triterpenes used in YAD-S and YAD-B originate from engineered Saccharomyces cerevisiae. YAD adjuvants have been demonstrated the safety and efficacy of triterpene oils in emulsion adjuvant formulations.

Details of YAD Nanoemulsion Adjuvants

YAD nanoemulsion adjuvants are formulated like MF59. They have an average particle size of ~180 nm, have been filtered through a 0.2 μm filter, and are verified sterile. Endotoxin levels are <1 EU/mL. The emulsions are ready to be mixed in a 1:1 ratio with antigen for injection. When stored at 4°C the emulsions should be stable for at least a year.

• Particle size and stability testing

Table 1 The average change in nanoemulsion size over 24 months when stored at 4°C. (Tateno, 2020)

• Immunization test

Total IgG measured against a split-virus, quadrivalent influenza vaccine in mouse serum three weeks after subcutaneous boost. Each circle represents a single animal.

Fig. 2 Mouse total IgG against quadrivalent influenza antigen. (Tateno, 2020)

• GC-MS Analysis

Purity of triterpene via GC-MS (>98%, see attached) and NMR

Heavy metals (arsenic, cadmium, lead, mercury) were not detected at 0.001 ppm

Fig.3 GC-MS analysis of squalene for adjuvant formulation. (Tateno, 2020)

YAD Nanoemulsion Adjuvants

As an industry-leading vaccine development services provider, Creative Biolabs is more than happy to launch YAD Nanoemulsion Adjuvants to global clients. We believe that yeast-derived YAD Nanoemulsion Adjuvants will bring new choices.

Advantages of YAD Nanoemulsion Adjuvants

• High purity and no pollution.
• Stable production conditions and material sources.
• Environmentally friendly and consistent with animal protection concept.

If you are looking for quality-stable Squalene, or you have any questions about YAD Nanoemulsion Adjuvants, please don't hesitate to contact us for more information.

References

1. Montana, M.; et al. Safety review: squalene and thimerosal in vaccines. Therapie. 2010, 65(6): 533-41.
2. Tateno, M.; et al. Synthetic Biology-derived triterpenes as efficacious immunomodulating adjuvants. Sci Rep. 2020, 10(1): 17090.

All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.