PROBLEM TO BE SOLVED: To provide an anti-Epiregulin antibody showing species cross reactivity between cynomolgus monkeys as non-human animals and humans, an anti-Epiregulin antibody with suppressed chemical degradation, an anti-Epiregulin antibody with a reduced isoelectric point, an anti-Epiregulin antibody with an increased heat denaturation intermediate temperature, and an anti-Epiregulin antibody with reduced associate amount.SOLUTION: The present invention provides an anti-Epiregulin antibody appropriately substituting amino acid residues in the variable region sequence of a humanized EP27 antibody that inhibits cancer cell proliferation by exerting cytotoxic and neutralizing activities against cancer cells expressing anti-human Epiregulin.SELECTED DRAWING: None【課題】非ヒト動物であるカニクイザル及びヒト動物間の種交差反応性を示す抗Epiregulin抗体、化学的分解が抑制された抗Epiregulin抗体、等電点が低下した抗Epiregulin抗体、熱変性中間温度が上昇した抗Epiregulin抗体、会合体量の低減された抗Epiregulin抗体の提供。【解決手段】抗ヒトEpiregulinを発現する癌細胞に対して細胞傷害活性および中和活性を発揮することによって癌細胞の増殖を阻害するヒト化EP27抗体の可変領域配列中のアミノ酸残基を適宜置換した抗Epiregulin抗体。【選択図】なし
