Binding of natural dog IgM (regardless of infection status) to fucosylated LacdiNAc (LDNF) and chitobiose was significantly above background levels for all three sera, but was higher for the chemically stripped Dirofilaria glycans than for the native structures (Fig. 10a); on the other hand, pronounced IgG binding to natural N-glycans as well as to fucosylated LacdiNAc was detected only for the infected dogs, while IgG from the control and infected dogs also bound fucosylated and non-fucosylated forms of chitobiose (Fig. 10b). Here, CD40LG is linked to infection.