Filariasis asymptomatically infected donors have lower levels of disialylated IgG compared to endemic normals.

Helminths induce strong regulatory and T helper 2-type responses, whereby antibody-derived host protection and regulation are essential components. Lymphatic filariasis is an immune-mediated spectral disease that manifests as two main clinical outcomes: chronic pathology or asymptomatic infection. These outcomes depend on a multitude of factors, including parasite-induced immunoregulation and host genetic background; antibody responses contribute to this outcome. N-glycosylation of the Fc region of antibodies is a post-translational modification required for the structure and molecular function, influencing host inflammatory and regulatory responses. Altered IgG glycosylation correlates with disease, whereby decreased galactosylation is associated with inflammation while increased sialylation is associated with anti-inflammatory responses. We purified N-linked glycans from the Fc region of total IgG from Wuchereria bancrofti-infected patients characterizing the two clinical manifestations (chronic pathology and asymptomatic infection) and compared them to infection-free endemic normals. Using capillary electrophoresis, we found that there was no difference in galactosylation of total IgG between the three groups; however, asymptomatically infected patients had significantly lower levels of disialylated IgG compared to endemic normals and patients with pathology. These data suggest that while galactosylation does not contribute to disease outcome, sialylation may be involved in asymptomatic infection.