Parasitic helminths express various antigenic
carbohydrates, which often account for serological cross-reactions. In serodiagnosis, it is essential to inspect cross-reactivity between the target parasite and other parasites in order to assess diagnostic performance. Our previous study showed that the
Galbeta1-6Gal sequence was a common
epitope between Echinococcus multilocularis (Em) and E. granulosus (Eg). Furthermore, compounds with this sequence from Fasciola hepatica (Fh) reportedly were recognized by sera with Eg
infection. Our aim is to investigate whether this sequence is one of the widely common
epitopes in many kinds of parasites. For various parasites, sera with Fh
infection cross-reacted at the highest frequency (71.4%) against Em
antigen. In patients with other
parasitic infections, sera showed cross-reactions against Fh
antigen bound to Em
antigen with a high frequency (23.7%). Binding inhibition tests with commercial
Galbeta1-6Gal disaccharide showed that
Galbeta1-6Gal was the common
epitope between not only Em, Eg and Fh, but also between various other parasites. Furthermore, the presence of the
Galbeta1-6Gal epitope in Em
antigen was confirmed by immunoblot testing with the specific antibody for this sequence. This study showed that the
Galbeta1-6Gal sequence is one of the antigenic
epitopes that accounts for serological cross-reactivity between Em and various other parasites.