ISCOM

Immune stimulating complexes (ISCOMs) are spherical open cage-like structures (typically 40 nm in diameter) that are spontaneously formed when mixing together cholesterol, phospholipids and Quillaja saponins under a specific stoichiometry. The complex displays immune stimulating properties and is thus mainly used as a vaccine adjuvant in order to induce a stronger immune response and longer protection.ISCOM technology was invented in 1982 by Professor Bror Morein at the Swedish University of Agricultural Sciences in Uppsala. The key components of ISCOMs are the Quillaja saponins, which are derived from the bark of the Chilean soap-bark tree Quillaja saponaria Molina. Quillaja saponins are well known for their ability to activate the immune system. It is also known that saponins in general can have toxic side-effects, including the induction of haemolysis. However, when Quillaia saponins, cholesterol and phospholipids are mixed under the specific stoichiometry that forms ISCOMs, this haemolytic activity is practically eliminated, while the adjuvant activity is retained.ISCOM-Matrix technology offers several immunological and practical advantages over currently available adjuvants. Most adjuvants on the market today mainly activate the humoral immune response (i.e. give an antibody response). There is, however, a clear need for adjuvants able to induce a cell-mediated immune response as well. ISCOM technology generally induces strong activation of both the cell-mediated (Th1 response) and the humoral arms (Th2 response) of the immune system. This generates all classes and sub-classes of antibodies, as well as potent cellular responses, e.g. cytotoxic T lymphocytes.