Western blot analysis of H. pylori cell lysate and the 58-kDa purified antigen. Lane 1, immunostaining with nonimmunized-rabbit serum; lane 2, immunostaining with polyclonal rabbit IgG to H. pylori cell lysate; lane 3, immunostaining with rabbit IgG-monospecific antibody to the 58-kDa purified antigen. A highly reactive band was identified at 58 kDa by using rabbit IgG anti-H. pylori lysate and the anti-58-kDa antigen. Molecular mass markers (bands are not shown but are indicated by arrows) include phosphorylase B (97.4 kDa), bovine serum albumin (66.2 kDa), glutamate dehydrogenase (55.0 kDa), ovalbumin (42.7 kDa), aldolase (40 kDa), carbonic anhydrase (31 kDa), and soybean trypsin inhibitor (21.5 kDa).