Include carbohydrate receptor binding domain, the antigen binding activity weaker antigen-binding molecule at pH in the early endosomes as compared to antigen-binding activity at pH in plasma, as well as pharmaceutical compositions comprising said antigen binding molecule, and their preparation methods are disclosed. The use of antigen-binding molecules of the invention, along with uptake into the cell of an antigen is promoted, it is possible to increase the number of antigen with which an antibody of the molecule can bind to the plasma by administration of an antibody as well as promoting the reduction antigens, it is possible to prolong the pharmacokinetics of the antibody.糖鎖受容体結合ドメインを含み、血漿中でのｐＨにおける抗原結合活性と比較して早期エンドソーム内でのｐＨにおける抗原結合活性が弱い抗原結合分子、ならびに当該抗原結合分子を含む医薬組成物、およびそれらの製造方法が開示される。本願発明の抗原結合分子を用いることにより、抗原の細胞内への取込が促進されるとともに、１分子の抗体が結合できる抗原の数を増加させることが可能になり、抗体の投与により血漿中の抗原減少を促進するとともに、抗体の薬物動態を長くすることが可能となる。
