The invention provides a conjugate comprising an antigen and a carrier molecule, wherein the carrier molecule comprises a spr0096 antigen and a spr2021 antigen. spr0096 and spr2021 are Streptococcus pneumoniae antigens. The conjugate may be used in a method for raising an immune response in a mammal, the method comprising administering the conjugate to the mammal. Also provided are pharmaceutical compositions, particularly vaccines, comprising the conjugate.
