Cross-reactivity of anti-H pylori antibodies with membrane antigens of human erythrocytes

Abstract

Aim: To investigate whether anti-H pylori antibodies have cross-reaction with antigens of erythrocyte membrane.

Methods: Blood samples were collected from 14 volunteers (8 positive and 6 negative for H pylori detected by (13)C-urea breath test) of the general population. Erythrocyte membrane proteins of the subjects were examined by Western blot using anti-H pylori serum. The proteins related to the positive bands were identified by mass spectrum analysis.

Results: Anti-H pylori antibodies had cross-reaction with the proteins of about 50 kDa of erythrocyte membranes in all samples independent of H pylori infection. One protein in the positive band was identified as Chain S, the crystal structure of the cytoplasmic domain of human erythrocyte Band-3 protein.

Conclusion: Anti-H pylori antibodies cross-react with some antigens of human erythrocyte membrane, which may provide a clue for the relationship between H pylori infection and vascular disorders.

Figure 1

Anti-H pylori serum immunoreacted with erythrocyte membrane proteins in Western blot. A: incubated with anti-H pylori serum of rabbit; B: incubated with normal serum of rabbit. 01-07: the number of erythrocyte membrane protein samples. Hp: H pylori NCTC11637; M: prestained molecular weight standards marker.

Figure 2

SDS-PAGE of erythrocyte membrane proteins. 03,02,08: the code of erythrocyte membrane protein samples. M: prestained molecular weight standards marker.