7.3.3　Archaeosomes

Archaeosomes are a novel class of potential vaccine adjuvants shown to induce strong cellular and humoral immune responses to antigens in vivo.Archaeosomes consist of liposomes formed with lipids containing the characteristic ether linkages of archaea between the carbon chains and the glycerol backbone.Vaccination with antigen encapsulated within archaeosomes formed with the total polar lipids (TPL) from various archaea species (e.g.Methanobrevibacter smithii) has been shown to enhance the immunogenicity of a broad range of antigens.In preclinical studies, they were able to mediate protection from pathogens such as Listeria monocytogenes as well as solid and metastatic tumors.Semi-synthetic glycerolipids such as sulfated S-lactosylarchaeol (SLA)either alone or mixed with uncharged glycolipid (lactosylarchaeol, LA) have been used to form archaeosomes capable of enhancing antigen immunogenicity.These semi-synthetic formulations offer many advantages such as homogeneity/purity, consistency of manufacturing and/or ease of synthesis when compared to previous TPL or other complex semi-synthetic archaeosome formulations.In addition, they have been shown to be well-tolerated with a favorable safety profile when administered intramuscularly in vivo, while stimulating strong cytokine secretion, immune cell recruitment and antigen uptake at the vaccination site.In preliminary pre-clinical studies, certain TPL archaeosome-adjuvanted vaccines were shown to be superior to those adjuvanted with conventional liposomes or alum when administered intraperitoneally or subcutaneously [11, 14].(https://www.daowen.com)