Expression of the CHO-131 epitope by transfected CHO cells.
(A) CHO-131 stains at a high level the transfectant CHO/FucT-VII/C2GnT (FT-VII/C2), but not CHO/FucT-VII (FT-VII). The transfectants CHO/FucT-VII/C2GnT and CHO/FucT-VII were labeled with the indicated concentrations of CHO-131 or the anti-sLeX mAb CSLEX-1. Nonspecific antibody labeling was determined by the use of an isotype negative control mAb (thin solid lines). Cell staining levels were examined by flow cytometry. Representative data from multiple repetitions are shown. (B) CHO-131 reactivity requires sialic acid. The transfectant CHO/PSGL-1/FucT-VII/C2GnT was subjected to neuraminidase (0.25 U) or sham treatment and then labeled with CHO-131 or 215 (anti–PSGL-1) as indicated. Nonspecific antibody labeling was determined with the use of the appropriate isotype negative control mAbs (dotted line; mouse IgM control is shown). Cell staining levels were examined by flow cytometry, and 10 000 cells were examined per sample. Representative data from multiple repetitions are shown.
