('T') of the pre-erythrocytic circumsporozoite protein (CSP) of the Plasmodium falciparum malaria parasite together with a viral surface antigen ('S') of the hepatitis B virus (HBsAg). This protein was then mixed with additional HBsAg to improve purification, hence the extra "S". Together, these two protein components assemble into soluble virus-like particles similar to the outer shell of a hepatitis B virus. A chemical adjuvant (AS01, specifically AS01E) was added to increase the immune system response. Infection is prevented by inducing humoral and cellular immunity, with high antibody titers, that block the parasite from infecting the liver. The T-cell epitope of CSP is O-fucosylated in Plasmodium falciparum and Plasmodium vivax, while the RTS,S vaccine produced in yeast is not. References Further reading External links Mosquirix: Product information Mosquirix: Public Assessment Report Peptide vaccines Subunit vaccines Malaria