PROBLEM TO BE SOLVED: To provide means for classifying a plurality of antibodies against cell surface antigens rapidly.SOLUTION: The invention relates to antibodies having a specific binding property to CD73 defined by a heavy chain variable region and a light chain variable region comprising a heavy chain variable region CDR1, CDR2 and CDR3, and a light chain variable region CDR1, CDR2, and CDR3 which consists of specific amino acid sequences respectively, or showing 90% or more identity to a specific amino acid sequence. And the invention further relates to a nucleic acid molecule encoding the heavy chain variable region and/or the light chain variable region of antibodies, a vector expressing the nucleic acid molecule, and a transformant introduced with the nucleic acid molecule.【課題】細胞表面抗原に対する複数の抗体を迅速に分類する手段の提供。【解決手段】それぞれ特定のアミノ酸配列からなる重鎖可変領域CDR1、CDR2及びCDR3と軽鎖可変領域CDR1、CDR2及びCDR3を備える、又は特定のアミノ酸配列と９０％以上の同一性を示す重鎖可変領域及び軽鎖可変領域で規定される、CD73に対する特異的結合性を有する抗体。また、抗体の重鎖可変領域及び／又は軽鎖可変領域をコードする核酸分子、核酸分子を発現するベクター及び核酸分子が導入された形質転換体。【選択図】なし
