Serum antibodies to Helicobacter hepaticus and Helicobacter pylori in patients with chronic liver disease

Abstract

Background: Bile tolerant helicobacter species such as H hepaticus and H bilis have frequently been reported to cause hepatitis in mice and other rodents.

Aims: To investigate the possible pathogenic role of these and other helicobacter species in chronic liver disease in humans.

Methods: Serum samples from 144 patients with various chronic liver diseases, 30 patients with primary sclerosing cholangitis (PSC), and 48 healthy blood donors were analysed for antibodies against H hepaticus murine strain CCUG 33637 and H pylori strain CCUG 17874. Cell surface proteins of H hepaticus were extracted by acid glycine buffer and used in an enzyme immunoassay (EIA) and immunoblot (IB).

Results: 56 of 144 (39%) patients with chronic liver diseases and six of 30 (20%) with PSC showed increased antibody concentrations in the H hepaticus EIA; in the H pylori EIA the numbers were 58% and 13% respectively. Compared with the healthy blood donors the antibody reactivity against the two helicobacter species was not increased (46% and 48% respectively). Patient serum samples retested by the H hepaticus EIA after absorption with sonicated H pylori cells remained positive in 12 of 37 (33%) serum samples. Distinct antibody reactivity to 55-65 kDa proteins was observed by H hepaticus IB, after the absorption step, and was considered specific for H hepaticus. These 12 serum samples were from patients with chronic alcoholic liver disease.

Conclusions: Antibodies to H hepaticus, often cross reacting with H pylori, occur frequently in patients with chronic liver diseases, with no clear cut relation to specific diagnostic groups. The pathogenic significance of these findings is not known.

Figure 1

Protein profiles of the acid glycine extracted cell surface proteins of Helicobacter pylori (lanes 1 and 2) and Helicobacter hepaticus (lanes 3 and 4) separated by SDS-PAGE (8-18%) and stained with silver.

Figure 2

Antibody response to cell surface proteins of Helicobacter hepaticus (A and C) and Helicobacter pylori (B and D) was analysed by immunoblotting with serum samples from patients with chronic liver disease (lanes 1 to 11). Lane 12 represents the reference standard. In (C) and (D) serum samples were absorbed with sonicated helicobacter cells.