Primary biliary cirrhosis following lactobacillus vaccination for recurrent vaginitis

Background/Aims Antimitochondrial antibodies directed against the E2 subunit of the pyruvate dehydrogenase complex, PDC-E2, and other mitochondrial 2-oxoacid dehydrogenases (AMA-M2) are the hallmark for diagnosis of primary biliary cirrhosis (PBC). AMA-M2 formation as an early step in the pathogenesis of PBC has recently been assumed to be triggered by bacterial mimics of the E2 subunit and certain reactant xenobiotics. We report a case of symptomatic PBC diagnosed after sequential immunization with a lactobacillus vaccine for recurrent vaginitis over years. Methods Serum AMA-M2 specificity of the patient was evaluated by indirect immunofluorescence, immunoblotting and ELISA. Serum antibody responses against pyruvate dehydrogenase complex-E2 subunit (PDC-E2212–226), the major PBC-specific mitochondrial autoepitope, and microbial mimics revealed cross-reactivity with beta-galactosidase of Lactobacillus delbrueckii (LACDE BGAL266–280) which shows a high local homology with that of Lactobacillus species administered via the vaccine. The relative affinity of antibody reactivity to LACDE BGAL266–280 was significantly higher than that against human PDC-E2212–226. Conclusions We conclude that lactobacillus vaccination therapy may be another culprit for the development of PBC in genetically susceptible women.