Immunological implications of structural mimicry between a dodecapeptide and a carbohydrate moiety

The immunogenicity and antibody cross-reactivity of two chemically differen t but structurally equivalent molecular mimics were analyzed by presenting them to the immune system in different modes. The observed differences in I gM and IgG responses in terms of cross-reactivity with the mimicking antige n could reflect the differential proliferative abilities of the correspondi ng B-cells. Modification of the T-cell help, either by using a promiscuous T-cell epitope or by prepriming. led to the shift in the antibody response towards the mimicking epitope. Also. the anti-sugar antibodies could be boo sted using a carbohydrate mimicking peptide on cross-immunization. Thus. th e carbohydrate-peptide mimicry appears to be a topological quasi-equivalenc e reflected differently in terms of antibody response during maturation. (C ) 2001 Elsevier Science Ltd. All rights reserved.