Provided is a novel composition. Provided is a composition for cytotoxic T cell depletion, comprising an anti-LAG-3 antibody or a binding fragment thereof having the properties described in (i) to (iii) below: (i) having in vitro ADCC activity； (ii) reducing, in a low fucose form, the number of LAG-3 positive cells in vivo； and (iii) binding to activated human T cells.
