Immunoblots of deglycosylated gp-Fy. The protein was purified by affinity chromatography and SDS-PAGE and digested with N-glycosidase F as explained in Materials and Methods. After digestion, the samples were run on SDS-PAGE minigels, electrotransferred onto nitrocellulose membranes, and immunoblotted with antibody 6615 (A) and antibody anti-Fy6 (B). The antibodies were detected by the horseradish peroxidase-conjugate substrate kit (Bio-Rad Laboratories, Inc, Richmond, CA). The carbohydrate determination was performed with the DIG glycan detection kit (Mannheim Boehringer Biochemicals Co, Indianapolis, IN) (C). A 0.5 μg aliquot of gp-Fy was analyzed in each lane. Lane 1, control and lane 2, treated samples.