The present invention relates to a monoclonal antibody against MELK. Further, the present invention provides a method for diagnosing a MELK-related disease, a method for detecting a MELK protein, a method for evaluating a drug effect after a treatment with a MELK inhibitor and a method for screening a subject for whom a treatment with a MELK inhibitor is highly efficacious, each method comprising using the aforesaid antibody, and a diagnostic reagent containing the aforesaid antibody.本發明係關於針對MELK的單株抗體。再者，本發明提供使用該抗體來診斷MELK關連病症之方法、檢測MELK蛋白質方法、判定利用MELK抑制劑治療後之藥效之方法、篩選藉由MELK抑制劑獲致之治療效果高之對象之方法、及含有該抗體之診斷用藥。
