Licensed liposomal vaccines and adjuvants in the antigen delivery system

Abstract

Liposomes (LSs) are promising nanoparticles with unique properties such as controlled nanosize, large surface area, increased reactivity, and ability to undergo modification. Worldwide, licensed liposomal forms of antibiotics, hormones, antioxidants, cytostatics, ophthalmic drugs, etc., are available on the pharmaceutical market. This review focuses on the adjuvant properties of LSs in the production of vaccines (VACs). LS-VACs have the following advantages: antigens with low immunogenicity can become highly immunogenic; LSs can include both hydrophilic and hydrophobic antigens; LSs allow to achieve a prolonged specific action of antibodies; and LSs reduce the toxicity and pyrogenicity of encapsulated antigens and adjuvants. The immune response is influenced by the composition of the liposomal membrane, physicochemical characteristics of lipids, antigen localization in LSs, interaction of LSs with complement, and a number of proteins, which leads to opsonization. The major requirements for adjuvants are their ability to enhance the immune response, biodegradability, and elimination from the organism, and LSs fully meet these requirements. The effectiveness and safety of LSs as carriers in the antigen delivery system have been proven by the long-term clinical use of licensed vaccines against hepatitis A, influenza, herpes zoster, malaria, and COVID-19.

Innovative Encapsulation Strategies for Food, Industrial, and Pharmaceutical Applications

“…EOs from Melaleuca alternifolia , Eucalyptus globulus , and Artemisia afra were encapsulated in liposomes composed of diastearoyl phosphatidylethanolamine and diastearoyl phosphatidylcholine, using reverse phase evaporation technique [64] . Other investigators have used liposomal encapsulation of EOs, particularly those from Eucalyptus globulus Both.,, [25] Zanthoxylum tingoassuiba , [26] Eucalyptus camaldulensis , [27] Eugenia uniflora L., [28] Anethum graveolens , [65] Zanthoxylum tingoassuiba , [26] Artemisia arborescens L., [66] and Santolina insularis [67] …”

“…Depending on the method, microcapsules of 3 to 800 μm (mononuclear, multinuclear, or matrix) or nanoparticles (capsules or spheres) with a size range of 10 to 1000 nm can be generated [2] . Several encapsulation methods are available such as microencapsulation, NPs encapsulation, liposomal encapsulation, polymer encapsulation, spray drying (SD), coacervation, and emulsification [19–39] . The most popular methods for encapsulating sensitive medications (pharmaceutics) and sensitive dietary supplements remains spray‐drying and freeze‐drying [8] …”

Azoximer bromide and hydroxyapatite: promising immune adjuvants in cancer

“…The recent development of mRNA vaccines has changed the use of traditional vaccines. Additionally, advances in nanotechnology have involved messenger (m)RNA vaccine delivery vehicles to support higher efficacy, as observed in prospective studies that include non-diseased populations 10 , 11 . The mRNA molecules serve as an immunogen and adjuvant due to the intrinsic immunostimulatory properties of such a vaccine.…”

Liposomes: from August Wassermann to Vaccines Against COVID-19

“…The mRNA vaccine development platform based on lipid nanosystem was first used for COVID-19 vaccine creation by Pfizer-BioNTech and Moderna [ 66 ]. Unlike traditional vaccines, which can deliver an inactivated or attenuated version of the virus (such as a capsular protein), these vaccines deliver genetic information to the body, synthesizing a protein to generate an immune response.…”