T-CELL, ANTIBODY, AND CYTOKINE RESPONSES TO HOMOLOGS OF THE 60-KILODALTON HEAT-SHOCK-PROTEIN IN HELICOBACTER-PYLORI INFECTION

For Helicobacter pylori, the hsp60 heat shock protein encoded by hspB is being considered as a potential candidate for subunit vaccines, We investigated the humoral and cellular responses to H. pylori hsp60 and its cross-reactivity with the homologous Mycobacterium bovis p65 prot ein and autologous human hsp60 protein. H. pylori-infected persons had significantly higher levels than uninfected persons of serum immunogl obulin G antibodies recognizing H. pylori hsp60, but not M. bovis p65 or human hsp60, as determined by enzyme-linked immunosorbent assay, In contrast, immunoblotting demonstrated cross-reactivity of H. pylori h sp60 with human hsp60. T-cell recognition of H. pylori hsp60 was found in both infected and uninfected subjects, and there was no recognitio n of human hsp60, T cells from infected and uninfected subjects that h ad been activated in response to H. pylori hsp60 or M. bovis p65 were phenotypically similar but appeared to secrete different levels of gam ma interferon and interleukin-10. These results demonstrate an apparen t difference in the epitopes recognized by the T and B cells respondin g to H. pylori hsp60 in H. pylori-infected persons, In contrast to the T-cell responses, which were highly variable in all subjects and show ed no recognition of autologous proteins, a specific B-cell response t hat may have cross-reactivity to human hsp60 is evident in some infect ed subjects.