IgG1 and IgG2a responses specific to Trichinella spiralis during subsequent infection with Heligmosomoides polygyrus in BALB-c mice

The aim of this study was to examine whether the profile of IgG1 and IgG2a responses to Trichinella spiralis is changed by subsequent infection with Heligmosomoides polygyrus. IgG1 and IgG2a antibodies were analysed in terms of Th2 related events evoked by both species of nematodes, although with a different parasitic result. T. spiralis antigens were recognized by IgG1 antibody from mice infected with T. spiralis and/or with H. polygyrus. IgG1 antibody from mice infected with T. spiralis did not recognize excretory-secretory H. polygyrus products. IgG2a antibodies from a T. spiralis and/or H. polygyrus infection recognized somatic antigens of H. polygyrus. T. spiralis antigens were only specifically recognized by IgG2a from T. spiralis infected mice. Subsequent infection with H. polygyrus inhibited the recognition of T. spiralis antigens. Previous infection with T. spiralis had only marginal effects on the course of H. polygyrus infection. Additionally, H. polygyrus altered the IgG1 and IgG2a profile of antibody responses to T. spiralis.