Anti-HPA-1a antibodies in FNAIT display a pronounced lowering of Fc fucosylation. Relative expression levels of major IgG-Fc Asn297 glycoforms for both total IgG1 (x-axis) and antigen-specific IgG1 (y-axis) for 48 FNAIT anti-HPA-1a serum samples (A-D). Serum populations were analyzed for Fc galactosylation (A), sialylation (B), bisection (C), and fucosylation (D). The statistical outcome between 2-tailed paired Student t test analysis of total IgG1 vs specific antibodies is listed in each panel. The diagonal, dotted line represents the equal ratio between total IgG1 and the specific antibody.