Cross-reactive epitopes present in campylobacter jejuni serotypes isolated from enteritis patients

Area of Science:

• Immunology
• Microbiology
• Neuroscience

Background:

• Campylobacter jejuni infections are a common trigger for autoimmune neuropathies, particularly Guillain-Barre syndrome (GBS).
• Molecular mimicry between bacterial lipopolysaccharides (LPSs) and human gangliosides is hypothesized to cause cross-reactive antibodies, contributing to GBS pathogenesis.

Purpose of the Study:

• To identify cross-reactive epitopes in C. jejuni LPSs from enteritis patients.
• To assess the antigen reactivity of these epitopes.

Main Methods:

• Stool specimens from 21 enteritis patients without neurological symptoms were analyzed.
• Seven C. jejuni serotypes (0:27, 0:6/0:7, 0:38, 0:3, 0:1/0:44, 0:19, 0:37) were identified using the Penner system.
• Binding studies with cholera toxin-B subunit and peanut agglutinin, along with analysis of GBS patient sera, were performed.

Main Results:

• Ganglioside-like epitopes were detected in C. jejuni strains serotypes 0:37, 0:19, and 0:27.
• These three LPSs demonstrated reactivity with sera from GBS patients with confirmed C. jejuni exposure and high anti-ganglioside antibody titers.
• Serotype 0:19, typically rare in enteritis, was identified and associated with GBS.

Conclusions:

• Certain C. jejuni LPSs, specifically from serotypes 0:37, 0:19, and 0:27, contain cross-reactive ganglioside-like epitopes.
• These epitopes likely play a role in the induction of Guillain-Barre syndrome following C. jejuni infection.
• The findings support the molecular mimicry hypothesis in GBS pathogenesis.