Comparison of IgG3 responses to carbohydrates following mouse infection or immunization with six species of Trichinella

The IgG3 antibody responses to carbohydrate epitopes were compared in BALB/c mice infected or immunized with six species of Trichinella: T. spiralis (T1), T. nativa (T2), T. britovi (T3), T6, T. nelsoni (T7), and T8. The dynamics of IgG3 responses and antigen recognition following infection or immunization were measured by ELISA and Western blot respectively, using glycosylated and deglycosylated larval crude extracts (LCE) prepared from homologous isolates. A high degree of protein glycosylation was found in all species and with similar profiles. Deglycosylation was completely achieved only in LCE from T1 and T6 isolates. The dynamics of IgG3 responses following infection or immunization significantly differed whereas the antigen recognition profiles appeared similar. Variations in the levels and antigen recognition patterns of IgG3 among the different species were apparent. The highest IgG3 levels were recorded in infections by the T8 isolate and the lowest in infections by the T6 isolate, whereas for immunization the highest IgG3 response was induced by T7 and the lowest by T8. Following antigen deglycosylation, the IgG3 responses were significantly reduced or abrogated and the recognition patterns markedly modified or suppressed in the different species of Trichinella.