An antigen-binding protein, or an antigen-binding fragment thereof that binds to a Lewis X type glycan on SLAMF7, comprising (1) a heavy chain variable domain comprising a VHCDR1 having the amino acid sequence GYTFTSYWIH; a VHCDR2 having the amino acid sequence EINPSNGRTNFNEKFKN and a VHCDR3 having the amino acid sequence VDYDEAY; and (ii) a light chain variable domain comprising a VLCDR1 having the amino acid sequence RSSKSLLHSNGITYLY, a VLCDR2 having the amino acid sequence QMSNLAS, and a VLCDR3 having the amino acid sequence AQNLELWT is provided. Methods of using the antibody for detecting or treating cancer, and a kit comprising the antibody are also provided.