Glycosylation of IgG changes under the influence of cytokines (IFN-γ, IL21, IL-17A etc.)

A group from Department of Endocrinology, Peking University First Hospital, Beijing, China, etc. has reported that the galactose level of IgG was increased by IFN-γ stimulation (p<0.05), and the sialylation of IgG was increased by IL-21 and IL-17A (p<0.05). This data was taken by using lectin microarrays.

But, what does this mean?