Echinococcus granulosus: induction of T-independent antibody response against protoscolex glycoconjugates in early experimental infection.

In this work CD4-knockout mice were used as a model to analyse the role of CD4+ T cells in the antibody response against Echinococcus granulosus immunization or experimental infection. Results obtained with mice immunized with protoscolex antigens indicated that these contain T-independent antigens. After infection, CD4-knockout mice and C57Bl/6 mice showed similar titres of specific antibodies indicating that T-independent antibody production was quantitatively important in early infection. We have also identified an antigenic fraction from protoscoleces (E4+) which induces CD4 T cell independent antibody response in early stages of infection. In conclusion, the results presented here directly support the existence of T-independent immunogens in E. granulosus protoscoleces and suggest that T-independent antibody response may be quantitatively important in early infection.