PROBLEM TO BE SOLVED: To provide human monoclonal antibodies, specifically the human antibody molecules against a human CD81, and to provide pharmaceutical compositions containing the same as an active ingredient.SOLUTION: The present invention provides an antibody against a human CD81 which binds to a region between amino acids 80 and 175, preferably a region between amino acids 113 and 175, in a specific amino acid sequence, wherein when the binding affinity to a native human CD81 is 100%, the binding affinity to a CD81 variant in which a part of the amino acid sequence is substituted is less than 40%, the antibody binds to a native human CD81 and has a T-cell migration inhibitory action.SELECTED DRAWING: None【課題】ヒトモノクローナル抗体分子、及び具体的には、ヒトＣＤ８１に対する前記ヒト抗体分子及びそれを有効成分として含む医薬組成物の提供。【解決手段】ヒトＣＤ８１に対する抗体であって、特定のアミノ酸配列中の８０～１７５番目の領域に結合する抗体。好ましくは１１３～１７５番目の領域に結合する抗体。前記アミノ酸配列の一部が置換されたＣＤ８１変異体に対する結合親和性が天然のヒトＣＤ８１に対する結合親和性を１００％とした時、４０％未満である抗体。天然のヒトＣＤ８１に結合し、かつＴ細胞遊送抑制作用を有する抗体。【選択図】なし
