Monophosphory Lipid A Adjuvant

Lipid A in lipopolysaccharide (LPS) is the primary inducer of inflammatory responses and possesses potent immunostimulatory effects; however, its toxicity limits its application as an immunological adjuvant or therapeutic agent. After hydrolyzing the main active component of LPS, lipid A, the monophosphorylated compound MPL is obtained. The toxicity of MPL is at most 0.08% of that of the parent LPS, while its immunomodulatory activity is largely, if not entirely, retained. MPL has been used as an adjuvant in seven vaccines.