Is there a link between the lipopolysaccharide of Helicobacter pylori gastric MALT lymphoma associated strains and lymphoma pathogenesis?

Abstract

The aim of this study was to investigate the Lewis antigen expression in Helicobacter pylori gastric MALT lymphoma associated strains in comparison to chronic gastritis only strains. Forty MALT strains (19 cagPAI (-) and 21 cagPAI (+)) and 39 cagPAI frequency-matched gastritis strains (17 cagPAI (-) and 22 cagPAI (+)) were included in this study. The lipopolyssacharide for each strain was extracted using a hot phenol method and the expression of Lex and Ley were investigated using Western Blot. The data were analyzed according to the strains' cagPAI status and vacA genotype. Lex was identified in 21 (52.5%) MALT strains and 29 (74.3%) gastritis strains. Ley was identified in 30 (75%) MALT strains and 31 (79.5%) gastritis strains. There was an association between cagPAI positivity and Lex expression among MALT strains (p<0.0001), but not in gastritis strains (p = 0.64). Among cagPAI (-) strains, isolates expressing solely Ley were associated with MALT with an odds ratio of 64.2 (95% CI 4.9-841.0) when compared to strains expressing both Lex and Ley. vacA genotypes did not modify the association between Lewis antigen expression and disease status. In conclusion, cagPAI (-) MALT strains have a particular Lewis antigen profile which could represent an adaptive mechanism to the host response or participate in MALT lymphomagenesis. © 2009 Lehours et al.