ST6GAL1 and autoimmune disease: The sialylation of IgG by ST6GAL1 is necessary for the anti-inflammatory effects of IVIG therapy in autoimmune disease, and variations in serum IgG sialylation have been widely associated with inflammatory diseases (Pagan et al., 2018; Nimmerjahn and Ravetch, 2008; Biermann et al., 2016).