Background: Ganglioside epitopes on Campylobacter jejuni are hypothesized as the key to the development and characterization of Guillain-Barré syndrome (GBS), but a comprehensive theory has yet to be established. A C jejuni gene, cst-II, involved in the biosynthesis of ganglioside-like lipo-oligosaccharide, shows a polymorphism (Asn/Thr51) that affects ganglioside epitopes.
Objective: To examine the hypothesis that this polymorphism determines autoantibody reactivity, and thereby neurologic presentations in GBS.
Methods: C jejuni isolates were collected from 105 GBS (including its variants) and 65 uncomplicated enteritis patients. The authors examined the frequency of cst-II and polymorphism (Asn/Thr51) in connection with the bacterial ganglioside epitopes, autoantibody reactivities against GM1, GD1a, and GQ1b, and patients' neurologic findings.
Results: Neuropathic strains more frequently had cst-II, in particular cst-II (Thr51), than did enteritic ones (85% vs 52%; p < 0.001). Strains with cst-II (Asn51) regularly expressed the GQ1b epitope (83%), whereas those with cst-II (Thr51) had the GM1 (92%) and GD1a (91%) epitopes. The presence of these bacterial epitopes in neuropathy patients corresponded to autoantibody reactivity. Patients infected with C jejuni (Asn51) more often were positive for anti-GQ1b IgG (56% vs 8%; p < 0.001) and had ophthalmoparesis (64% vs 13%; p < 0.001) and ataxia (42% vs 11%; p = 0.001). Patients who had C jejuni (Thr51) more frequently were positive for anti-GM1 (88% vs 35%; p < 0.001) and anti-GD1a IgG (52% vs 24%; p = 0.006) and had limb weakness (98% vs 71%; p < 0.001).
Conclusions: The genetic polymorphism of C jejuni determines autoantibody reactivity as well as the clinical presentation of Guillain-Barré syndrome (GBS), possibly through modification of the host-mimicking molecule. The GBS paradigm is the first to explain the detailed pathogenesis of a postinfectious, autoimmune-mediated, molecular mimicry-triggering disorder.