QS-21

QS-21 is a saponin derived from the bark of the Quillaja saponaria tree, commonly known as the soap bark tree. It is used as an adjuvant in vaccines to enhance the body's immune response to the vaccine's active ingredient.

History

QS-21 was first isolated and characterized in the 1960s by scientists studying the properties of the Quillaja saponaria tree. The tree, native to Chile, has been used for centuries in traditional medicine for its antimicrobial and anti-inflammatory properties.

Properties and Uses

QS-21 is a potent adjuvant, meaning it enhances the body's immune response to a vaccine's active ingredient. It does this by stimulating the production of antibody cells and T cells, which are crucial for a strong and effective immune response.

QS-21 is used in a variety of vaccines, including those for influenza, hepatitis, and malaria. It is also used in experimental vaccines for diseases such as HIV and cancer.

Safety and Side Effects

While QS-21 is generally considered safe, it can cause side effects in some people. These can include pain at the injection site, fever, and headache. In rare cases, severe allergic reactions can occur.

Future Research

Research is ongoing into the potential uses of QS-21 in new vaccines and treatments. This includes research into its use in vaccines for Alzheimer's disease, Parkinson's disease, and other neurodegenerative conditions.

See Also

• Adjuvant
• Vaccine
• Saponin
• Quillaja saponaria