Aluminum-based vaccines are the most widely used adjuvants for human and veterinary vaccines, but their development is hindered by poor protection efficiency and potential side effects. Outer membrane vesicles (OMVs) have shown great potential for adjuvant applications and have been successfully applied to various vaccine platforms. CD BioGlyco is an expert in the field of adjuvants, providing customers with homologous OMVs-, heterologous OMVs-, and click-OMVs-based adjuvant development services.

OMVs

OMVs are spherical, bilayered, membranous nanostructures naturally present in Gram-negative bacteria, mainly composed of lipopolysaccharides (LPS), outer membrane, periplasmic proteins, and phospholipids. OMVs productions vary in size, ranging from 20 nm to 300 nm in diameter. OMVs perform many different functions such as communication, waste disposal, and antigen or toxin delivery. OMVs carry many of the same surface antigens as bacterial surfaces and show great potential for application in vaccine development.

Fig.1 The functions of OMVs. (Balhuizen, 2021)

Advantages of OMVs

• Stable and intact at different temperatures and treatments
• Inanimate, non-replicative, and auxiliary
• A large number of immunogenic components related to the parent bacteria
• Involved in innate and adaptive immunity

Applications of OMVs

For decades, OMVs have been tested in animals and humans as vaccine components. At present, many successful experiments have developed OMVs with safety and immunostimulatory activities. In 1988, OMVs were first proposed as a carrier and adjuvant for meningococcal disease nasal vaccine. After that, it was found that the OMV vaccine derived from Shiga toxin-producing Escherichia coli (STEC) protects mice from Hemolytic Uremic Syndrome (HUS). OMV from Bordetella bronchiseptica protects mice from sublethal infection, and Salmonella enteritidis OMV protects against Salmonella enteritidis infection.

Fig.2 OMVs formation. (Micoli, 2020)

CD BioGlyco has extensive expertise in OMV-based adjuvant development. Depending on the target disease and antigen, we provide customers with three types of OMV:

• Homologous OMVs: By extracting OMVs directly from target Gram-negative bacteria.
• Heterologous OMVs: OMVs are modified with specific proteins or polysaccharides from heterologous pathogens. This method is suitable for the pathogenic bacteria that are highly enclosed bacteria or difficult to cultivate.
• Click-OMVs: Driving efficient adaptive immunity through immunogenic peptide or protein modifications, this approach is suitable for antigens that are possible to be expressed in bacteria.

CD BioGlyco is a leader in vaccine adjuvant development and has been working on OMVs-based adjuvant development. We provide our customers with a full range of OMV-based adjuvant development services based on our high-quality services and extensive experiences. If you are interested in our services, please contact us directly.

References:

1. Balhuizen, M.D.; et al. Outer membrane vesicle induction and isolation for vaccine development. Frontiers in Microbiology. 2021, 12:79.
2. Micoli, F.; MacLennan, C.A. Outer membrane vesicle vaccines. Seminars in Immunology. 2020, 50.