Adoptive immune cells obtained by a method including (a) obtaining mammalian antigen-presenting associated cells; (b) culturing the resulting cells from step (a) in a culture liquid contained in a culture vessel coated with a sugar chain-containing polymer; and (c) detaching the cells from step (b) by shaking the culture vessel without treating the cells with an enzyme and without using a cell detaching tool. A method for treating a malignant tumor, type I diabetes, an atopic allergic disease or an infection, by administering the adoptive immune cells to a patient. A pharmaceutical composition for treating a malignant tumor, type I diabetes, an atopic allergic disease or an infection, including the adoptive immune cells and a pharmaceutically acceptable carrier.