PROBLEM TO BE SOLVED: To provide a novel Streptococcus pneumoniae vaccine capable of appropriately protecting against serotypes 10A, 22F or 33F Streptococcus pneumoniae, and a method for producing the vaccine. A method for preparing an immunogenic conjugate comprising Streptococcus pneumoniae serotype 22F polysaccharide covalently linked to a carrier protein. Serotype 22F capsular polysaccharide isolate is reacted with 0.05-0.2 molar equivalents of periodate. 1 to 3 molar equivalents of a reaction terminator are added to obtain activated Streptococcus pneumoniae serotype 22F polysaccharide in which the degree of oxidation of the polysaccharide is between 10 and 20. The activated Streptococcus pneumoniae serotype 22F polysaccharide is mixed with a carrier protein and reacted with a reducing agent to form a conjugate. [Selection diagram] None【課題】血清型１０Ａ、２２Ｆ又は３３Ｆ肺炎連鎖球菌（Ｓｔｒｅｐｔｏｃｏｃｃｕｓ ｐｎｅｕｍｏｎｉａｅ）を適切に防御可能な新規肺炎連鎖球菌ワクチン、及び前記ワクチンの製造方法の提供。【解決手段】担体タンパク質に共有結合で連結された肺炎連鎖球菌血清型２２Ｆ多糖を含む免疫原性コンジュゲートを調製するための方法。血清型２２Ｆ莢膜多糖単離物を、０．０５～０．２モル当量のペルヨーデートと反応させる。１～３モル当量の反応停止剤を加え、多糖の酸化度が１０～２０の間である活性化肺炎連鎖球菌血清型２２Ｆ多糖を得る。前記活性化肺炎連鎖球菌血清型２２Ｆ多糖と担体タンパク質を混和し、還元剤と反応させてコンジュゲートを形成する。【選択図】なし
